Quasi-2D Dion-Jacobson(DJ)tin halide perovskite has attracted much attention due to its elimination of Van der Waals gap and enhanced environmental stability.However,the bulky organic spacers usually form a natural qu...Quasi-2D Dion-Jacobson(DJ)tin halide perovskite has attracted much attention due to its elimination of Van der Waals gap and enhanced environmental stability.However,the bulky organic spacers usually form a natural quantum well structure,which brings a large quantum barrier and poor film quality,further limiting the carrier transport and device performance.Here,we designed three organic spacers with different chain lengths(ethylenediamine(EDA),1,3-propanediamine(PDA),and 1,4-butanediamine(BDA))to investigate the quantum barrier dependence.Theoretical and experimental characterizations indicate that EDA with short chain can reduce the lattice distortion and dielectric confinement effect,which is beneficial to the effective dissociation of excitons and the inhibition of trap-free non-radiative relaxation.In addition,EDA cation shows strong interaction with the inorganic octahedron,realizing large aggregates in precursor solution and high-quality films with improved structural stability.Furthermore,femtosecond transient absorption proves that EDA cations can also weaken the formation of small n-phases with large quantum barrier to achieve effective carrier transport between different nphases.Finally,the quasi-2D DJ(EDA)FA_(9)Sn_(10)I_(31)solar cells achieves a 7.07%power conversion efficiency with good environment stability.Therefore,this work sheds light on the regulation of the quantum barrier and carrier transport through the chain length of organic spacer for qua si-2D DJ lead-free perovskites.展开更多
Nowadays, the soar of photovoltaic performance of perovskite solar cells has set off a fever in the study of metal halide perovskite materials. The excellent optoelectronic properties and defect tolerance feature allo...Nowadays, the soar of photovoltaic performance of perovskite solar cells has set off a fever in the study of metal halide perovskite materials. The excellent optoelectronic properties and defect tolerance feature allow metal halide perovskite to be employed in a wide variety of applications. This article provides a holistic review over the current progress and future prospects of metal halide perovskite materials in representative promising applications, including traditional optoelectronic devices(solar cells, light-emitting diodes, photodetectors, lasers), and cutting-edge technologies in terms of neuromorphic devices(artificial synapses and memristors) and pressure-induced emission. This review highlights the fundamentals, the current progress and the remaining challenges for each application, aiming to provide a comprehensive overview of the development status and a navigation of future research for metal halide perovskite materials and devices.展开更多
Perovskite solar cells(PSCs)emerging as a promising photovoltaic technology with high efficiency and low manufacturing cost have attracted the attention from all over the world.Both the efficiency and stability of PSC...Perovskite solar cells(PSCs)emerging as a promising photovoltaic technology with high efficiency and low manufacturing cost have attracted the attention from all over the world.Both the efficiency and stability of PSCs have increased steadily in recent years,and the research on reducing lead leakage and developing eco-friendly lead-free perovskites pushes forward the commercialization of PSCs step by step.This review summarizes the main progress of PSCs in 2020 and 2021 from the aspects of efficiency,stability,perovskite-based tandem devices,and lead-free PSCs.Moreover,a brief discussion on the development of PSC modules and its challenges toward practical application is provided.展开更多
Defect passivation is one of the most important strategies to boost both the efficiency and stability of perovskite solar cells(PSCs).Here,nontoxic and sustainable forest-based biomaterial,betulin,is first introduced ...Defect passivation is one of the most important strategies to boost both the efficiency and stability of perovskite solar cells(PSCs).Here,nontoxic and sustainable forest-based biomaterial,betulin,is first introduced into perovskites.The experiments and calculations reveal that betulin can effectively passivate the uncoordinated lead ions in perovskites via sharing the lone pair electrons of hydroxyl group,promoting charge transport.As a result,the power conversion efficiencies of the p-i-n planar PSCs remarkably increase from 19.14%to 21.15%,with the improvement of other parameters.The hydrogen bonds of betulin lock methylamine and halogen ions along the grain boundaries and on the film surface and thus suppress ion migration,further stabilizing perovskite crystal structures.These positive effects enable the PSCs to maintain 90%of the initial efficiency after 30 days in ambient air with 60%±5%relative humidity,75%after 300 h aging at 85℃,and 55%after 250 h light soaking,respectively.This work opens a new pathway for using nontoxic and low-cost biomaterials from forest to make highly efficient and stable PSCs.展开更多
Surface passivation via post-treatment is an important strategy for improving power conversion efficiency and operational stability of perovskite solar cells.However,so far the interaction mechanisms between passivati...Surface passivation via post-treatment is an important strategy for improving power conversion efficiency and operational stability of perovskite solar cells.However,so far the interaction mechanisms between passivating additive and perovskite are not well understood.Here,we report the atomic-scale interaction of surface passivating additive 2,2-difluoroethylammonium bromine(2FEABr)on the MAPbI_(3).It is found that the bulky 2FEA+cations tend to distribute at film surface,while the Br−anions diffuse from surface into bulk.A combination of 19F,207Pb,and 2H solid-state NMR further reveal the Br−anions’partial substitution for the I−sites,the restricted motion of partial MA+cations,and the firmed perovskite lattices,which would improve charge transport and stability of the perovskite films.Optical spectroscopy and ultraviolet photoelectron spectroscopy demonstrate that the 2FEABr induced surface passivation and energetic modification suppress the nonradiative recombination loss.These findings enable the efficiency of the p-i-n structured PSC significantly increasing from 19.44 to 21.06%,accompanied by excellent stability.Our work further establishes more knowledge link between passivating additive and PSC performance.展开更多
Nickel oxide(NiOx)has exhibited great potential as an inorganic hole transport layer(HTL)in perovskite solar cells(PSCs)due to its wide optical bandgap and superior stability.In this study,we have modulated the Ni26 v...Nickel oxide(NiOx)has exhibited great potential as an inorganic hole transport layer(HTL)in perovskite solar cells(PSCs)due to its wide optical bandgap and superior stability.In this study,we have modulated the Ni26 vacancies in NiOx film by controlling deposition temperature in a hot-casting process,resulting the change of coordination structure and charge state of NiOx.Moreover,the change of the HOMO level of NiOx makes it more compatible with perovskite to decrease energy losses and enhance hole carrier injection efficiency.Besides,the defect modulation in the electronic structure of NiOx is beneficial for increasing the electrical conductivity and mobility,which are considered to achieve the balance of charge carrier transport and avoid charge accumulation at the interface between perovskite and HTL effectively.Both experimental analyses and theoretical calculations reveal the increase of nickel vacancy defects change the electronic structure of NiOx by increasing the ratio of Ni3^+/Ni2^+-and improving the p-type characteristics.Accordingly,an optimal deposition temperature at 120℃enabled a 36.24%improvement in the power conversion efficiency compared to that deposited at room temperature(25℃).Therefore,this work provides a facile method to manipulate the electronic structure of NiOx to improve the charge carrier transport and photovoltaic performance of related PSCs.展开更多
Perovskite materials have made a great progress in terms of the power conversion efficiency(PCE), rising from 3.8% to 25.2%. To obtain pinhole-free, superior crystal, and high-quality perovskite films with less defect...Perovskite materials have made a great progress in terms of the power conversion efficiency(PCE), rising from 3.8% to 25.2%. To obtain pinhole-free, superior crystal, and high-quality perovskite films with less defect, intermediates transformation is important, which has been clearly studied and widely applied.In this review, we systematically summarize the commonly formed intermediates and detailedly analyze their mechanisms from five aspects:(1) Solvent-induced intermediate;(2) HI-induced intermediate;(3)CH3NH2-induced intermediate;(4) MAAc-induced intermediate;(5) other intermediates. Finally, we also provide some prospects on high-quality perovskite fabrication based on using intermediates prudently.展开更多
Perovskite solar cells(PSCs)have become the represent-atives of next generation of photovoltaics;nevertheless,their stability is insufficient for large scale deployment,particularly the reverse bias stability.Here,we ...Perovskite solar cells(PSCs)have become the represent-atives of next generation of photovoltaics;nevertheless,their stability is insufficient for large scale deployment,particularly the reverse bias stability.Here,we propose a transparent conducting oxide(TCO)and low-cost metal composite electrode to improve the stability of PSCs without sacrificing the efficiency.The TCO can block ion migrations and chemical reactions between the metal and perovskite,while the metal greatly enhances the conductivity of the composite electrode.As a result,composite electrode-PSCs achieved a power conversion efficiency(PCE)of 23.7%(certified 23.2%)and exhibited excellent stability,maintaining 95%of the initial PCE when applying a reverse bias of 4.0 V for 60 s and over 92%of the initial PCE after 1000 h continuous light soaking.This composite electrode strategy can be extended to different combinations of TCOs and metals.It opens a new avenue for improving the stability of PSCs.展开更多
After fast developing of single-junction perovskite solar cells and organic solar cells in the past 10 years,it is becoming harder and harder to improve their power conversion efficiencies.Tandem solar cells are recei...After fast developing of single-junction perovskite solar cells and organic solar cells in the past 10 years,it is becoming harder and harder to improve their power conversion efficiencies.Tandem solar cells are receiving more and more attention because they have much higher theoretical efficiency than single-junction solar cells.Good device performance has been achieved for perovskite/silicon and perovskite/perovskite tandem solar cells,including 2-terminal and 4-terminal structures.However,very few studies have been done about 4-terminal inorganic perovskite/organic tandem solar cells.In this work,semi-transparent inorganic perovskite solar cells and organic solar cells are used to fabricate 4-terminal inorganic perovskite/organic tandem solar cells,achieving a power conversion efficiency of 21.25%for the tandem cells with spin-coated perovskite layer.By using drop-coating instead of spin-coating to make the inorganic perovskite films,4-terminal tandem cells with an efficiency of 22.34%are made.The efficiency is higher than the reported 2-terminal and 4-terminal inorganic perovskite/organic tandem solar cells.In addition,equivalent 2-terminal tandem solar cells were fabricated by connecting the sub-cells in series.The stability of organic solar cells under continuous illumination is improved by using semi-transparent perovskite solar cells as filter.展开更多
Polarization means symmetry loss for light vibration along light propagation direction,which is a particular physical property of light.The polarization state is indecipherable for most polarization-insensitive detect...Polarization means symmetry loss for light vibration along light propagation direction,which is a particular physical property of light.The polarization state is indecipherable for most polarization-insensitive detectors.Polarization can carry and differentiate light information,and can be used in polarized light detection,polarization imaging and encryption communication[1].Photodetectors are the core component of some photoelectric devices[2]used in biomedical sensing,remote sensing,military field,etc.展开更多
Metal halide perovskite-based solar cells(PSCs) have rapidly-increased power conversion efficiency(PCE)exceeding 25% but poor stability especially under ultraviolet(UV) light. Meanwhile, non-radiative recombination ca...Metal halide perovskite-based solar cells(PSCs) have rapidly-increased power conversion efficiency(PCE)exceeding 25% but poor stability especially under ultraviolet(UV) light. Meanwhile, non-radiative recombination caused by diverse defects in perovskite absorbers and related interfaces is one of the major factors confining further development of PSCs. In this study, we systematically investigate the role of 2-(2-hydroxy-5-methylphenyl)benzotriazole(UVP) additive in perovskite layers. By adjusting the amount of doped UVP, the quality of perovskite absorbers is significantly improved with enlarged grains, longer lifetime and diffusion length of charge carriers. Furthermore, UVP not only reduces defects for less nonradiative recombination, but also matches energy level alignment for efficient interfacial charge extraction. X-ray photoelectron spectroscopy confirms that N-donor of UVP molecule coordinates with undercoordinated Pb^(2+) on the surface. Interestingly, UVP incorporated in PbI_(2) protects the perovskite by absorbing UV through the opening and closing of the chelating ring. Eventually, the UVP treated PSCs obtain a champion PCE of 22.46% with remarkably enhanced UV stability, retaining over 90% of initial PCE after 60 m W/cm^(2) strong UV irradiation for 9 h while the control maintaining only 74%. These results demonstrate a promising strategy fabricating passivated and UV-resistant perovskite materials simultaneously for efficient and stable perovskite photovoltaics.展开更多
Recently,perovskite solar cells(PSCs) have flourished,and their power conversion efficiency(PCE) has increased from the initial 3.8% to 25.2% in 2019,which is an unprecedented advance.However,usually high-efficiency a...Recently,perovskite solar cells(PSCs) have flourished,and their power conversion efficiency(PCE) has increased from the initial 3.8% to 25.2% in 2019,which is an unprecedented advance.However,usually high-efficiency and stable PSCs are small-area devices prepared by spin coating.This method is not suitable for the preparation of large-area devices in commercialization.Therefore,there is an urgent need to develop new materials and methods for the scalable fabrication of PSCs.In this review,we first describe the common small-area PSCs preparation methods,understand the nucleation and crystal growth kinetics of perovskite,and analyze the reasons that hinder the development of small-area devices to large-area devices.Next,in order to meet the challenges of PSC’s scalable fabrication,we summarize and analyze four strategies:scaling up precursor solutions,scalable deposition methods for large-area films,scaling up charge-transport layers and back electrodes,developing solar modules.Finally,challenges and prospects are proposed to help researchers prepare high-efficiency large-area PSCs.展开更多
Due to their excellent photoelectron chemical properties and suitable energy level alignment with perovskite,perylene diimide(PDI)derivatives are competitive non-fullerene electron transport material(ETM)candidates fo...Due to their excellent photoelectron chemical properties and suitable energy level alignment with perovskite,perylene diimide(PDI)derivatives are competitive non-fullerene electron transport material(ETM)candidates for perovskite solar cells(PSCs).However,the conjugated rigid plane structure of PDI units result in PDI-based ETMs tending to form large aggregates,limiting their application and photovoltaic performance.In this study,to restrict aggregation and further enhance the photovoltaic performance of PDI-type ETMs,two PDI-based ETMs,termed PDO-PDI2(dimer)and PDO-PDI3(trimer),were constructed by introducing a phenothiazine 5,5-dioxide(PDO)core building block.The research manifests that the optoelectronic properties and film formation property of PDO-PDI2 and PDO-PDI3 were deeply affected by the molecular spatial configuration.Applied in PSCs,PDO-PDI3 with threedimensional spiral molecular structure,exhibits superior electron extraction and transport properties,further achieving the best PCE of 18.72%and maintaining 93%of its initial efficiency after a 720-h aging test under ambient conditions.展开更多
Perovskite-based optoelectronic devices using organic–inorganic, metal halide, hybrid thin films have revolutionized the pathway towards constructing more efficient and stable photovoltaics and light-emitting electro...Perovskite-based optoelectronic devices using organic–inorganic, metal halide, hybrid thin films have revolutionized the pathway towards constructing more efficient and stable photovoltaics and light-emitting electronics [1,2]. Nevertheless, solutionprocessed polycrystalline perovskite films inevitably contain a high density of crystallographic or ionic defects.展开更多
Perovskite solar cells(PSCs)have attracted aggressive attention in the photovoltaic field in light of the rapid increasing power conversion efficiency.However,their large-scale application and commercialization are li...Perovskite solar cells(PSCs)have attracted aggressive attention in the photovoltaic field in light of the rapid increasing power conversion efficiency.However,their large-scale application and commercialization are limited by the toxicity issue of lead(Pb).Among all the lead-free perovskites,tin(Sn)-based perovskites have shown potential due to their low toxicity,ideal bandgap structure,high carrier mobility,and long hot carrier lifetime.Great progress of Sn-based PSCs has been realized in recent years,and the certified efficiency has now reached over 14%.Nevertheless,this record still falls far behind the theoretical calculations.This is likely due to the uncontrolled nucleation states and pronounced Sn(Ⅳ)vacancies.With insights into the methodologies resolving both issues,ligand engineering-assisted perovskite film fabrication dictates the state-of-the-art Sn-based PSCs.Herein,we summarize the role of ligand engineering during each state of film fabrication,ranging from the starting precursors to the ending fabricated bulks.The incorporation of ligands to suppress Sn~(2+)oxidation,passivate bulk defects,optimize crystal orientation,and improve stability is discussed,respectively.Finally,the remained challenges and perspectives toward advancing the performance of Sn-based PSCs are presented.We expect this review can draw a clear roadmap to facilitate Sn-based PSCs via ligand engineering.展开更多
Tin halide perovskites(THPs)have received extensive attention due to their low toxicity and excellent optoelectronic properties,and are considered to be the most promising alternatives to develop efficient lead-free p...Tin halide perovskites(THPs)have received extensive attention due to their low toxicity and excellent optoelectronic properties,and are considered to be the most promising alternatives to develop efficient lead-free perovskite solar cells.However,due to the unique and inherent characteristics of Sn^(2+)being easily oxidized to Sn^(4+)and fast crystallization,tin perovskite solar cells(TPSCs)show relatively poor performance and stability,compared to the lead counterparts.Recently,the introduction of bulky organic spacers into three-dimensional(3D)THPs for dimensional regulation can not only prevent the intrusion of water and oxygen,but also inhibit the self-doping effect and ion migration.In this review,we will detail how dimensional regulation enables TPSCs with high performance and superior stability.First,we summarize the intrinsic properties of THPs and analyze the root causes of their poor performance and instability.Next,we discuss the specific structure and types of the dimensional regulation strategy.Then,the mechanism of dimensional regulation is discussed in detail,mainly from inhibiting the Sn^(2+)oxidation,optimizing crystallization,passivating defects,and improving energy level alignment.Finally,future challenges and prospects for dimensional regulation are elaborated to help researchers develop more efficient and stable TPSCs.展开更多
Lead-free inorganic copper-silver-bismuth-halide materials have attracted more and more attention due to their environmental friendliness,high element abundance,and low cost.Here,we developed a strategy of one-step ga...Lead-free inorganic copper-silver-bismuth-halide materials have attracted more and more attention due to their environmental friendliness,high element abundance,and low cost.Here,we developed a strategy of one-step gas-solid-phase diffusioninduced reaction to fabricate a series of bandgap-tunable Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI bilayer films due to the atomic diffusion effect for the first time.By designing and regulating the sputtered Cu/Ag/Bi metal film thickness,the bandgap of Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI could be reduced from 2.06 to 1.78 eV.Solar cells with the structure of FTO/TiO_(2)/Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI/carbon were constructed,yielding a champion power conversion efficiency of 2.76%,which is the highest reported for this class of materials owing to the bandgap reduction and the peculiar bilayer structure.The current work provides a practical path for developing the next generation of efficient,stable,and environmentally friendly photovoltaic materials.展开更多
Organic-inorganic metal halide perovskite solar cells(PSCs) have recently been considered as one of the most competitive contenders to commercial silicon solar cells in the photovoltaic field.The deposition process of...Organic-inorganic metal halide perovskite solar cells(PSCs) have recently been considered as one of the most competitive contenders to commercial silicon solar cells in the photovoltaic field.The deposition process of a perovskite film is one of the most critical factors affecting the quality of the film formation and the photovoltaic performance.A hot-casting technique has been widely implemented to deposit high-quality perovskite films with large grain size,uniform thickness,and preferred crystalline orientation.In this review,we first review the classical nucleation and crystal growth theory and discuss those factors affecting the hot-casted perovskite film formation.Meanwhile,the effects of the deposition parameters such as temperature,thermal annealing,precursor chemistry,and atmosphere on the preparation of high-quality perovskite films and high-efficiency PSC devices are comprehensively discussed.The excellent stability of hot-casted perovskite films and integration with scalable deposition technology are conducive to the commercialization of PSCs.Finally,some open questions and future perspectives on the maturity of this technology toward the upscaling deposition of perovskite film for related optoelectronic devices are presented.展开更多
Perovskite quantum-dots (PQDs) have emerged as prominent candidates for intriguing photovoltaic application due to their superior optoelectronic properties such as multiple exciton generation, bandgap tunability, elec...Perovskite quantum-dots (PQDs) have emerged as prominent candidates for intriguing photovoltaic application due to their superior optoelectronic properties such as multiple exciton generation, bandgap tunability, electronic and surface chemistry properties, as well as flexible composition [1–5].展开更多
Tandem solar cells based on metal halide perovskites are advancing rapidly during last few years[1–17].The certified power conversion efficiency(PCE)for monolithic perovskite/silicon tandem solar cell reaches 32.5%[1...Tandem solar cells based on metal halide perovskites are advancing rapidly during last few years[1–17].The certified power conversion efficiency(PCE)for monolithic perovskite/silicon tandem solar cell reaches 32.5%[18].Since tandem solar cells contain more layers than single-junction solar cells,stress/strain control is an issue during fabrication and further practical operation.The stress can not only affect the stability of the perovskite layer but also change the optoelectronic properties of the films[19–23].展开更多
基金financially supported by the National Key Research and Development Program of China(2022YFE0118400)the National Natural Science Foundation of China(51702038)+1 种基金the Science&Technology Department of Sichuan Province(2020YFG0061)the Recruitment Program for Young Professionals。
文摘Quasi-2D Dion-Jacobson(DJ)tin halide perovskite has attracted much attention due to its elimination of Van der Waals gap and enhanced environmental stability.However,the bulky organic spacers usually form a natural quantum well structure,which brings a large quantum barrier and poor film quality,further limiting the carrier transport and device performance.Here,we designed three organic spacers with different chain lengths(ethylenediamine(EDA),1,3-propanediamine(PDA),and 1,4-butanediamine(BDA))to investigate the quantum barrier dependence.Theoretical and experimental characterizations indicate that EDA with short chain can reduce the lattice distortion and dielectric confinement effect,which is beneficial to the effective dissociation of excitons and the inhibition of trap-free non-radiative relaxation.In addition,EDA cation shows strong interaction with the inorganic octahedron,realizing large aggregates in precursor solution and high-quality films with improved structural stability.Furthermore,femtosecond transient absorption proves that EDA cations can also weaken the formation of small n-phases with large quantum barrier to achieve effective carrier transport between different nphases.Finally,the quasi-2D DJ(EDA)FA_(9)Sn_(10)I_(31)solar cells achieves a 7.07%power conversion efficiency with good environment stability.Therefore,this work sheds light on the regulation of the quantum barrier and carrier transport through the chain length of organic spacer for qua si-2D DJ lead-free perovskites.
基金the National Key Research and Development Program of China (2022YFB3803300)the open research fund of Songshan Lake Materials Laboratory (2021SLABFK02)the National Natural Science Foundation of China (21961160720)。
文摘Nowadays, the soar of photovoltaic performance of perovskite solar cells has set off a fever in the study of metal halide perovskite materials. The excellent optoelectronic properties and defect tolerance feature allow metal halide perovskite to be employed in a wide variety of applications. This article provides a holistic review over the current progress and future prospects of metal halide perovskite materials in representative promising applications, including traditional optoelectronic devices(solar cells, light-emitting diodes, photodetectors, lasers), and cutting-edge technologies in terms of neuromorphic devices(artificial synapses and memristors) and pressure-induced emission. This review highlights the fundamentals, the current progress and the remaining challenges for each application, aiming to provide a comprehensive overview of the development status and a navigation of future research for metal halide perovskite materials and devices.
基金supported by the National Natural Science Foundation of China(Grant Nos.11834011 and 12074245)the support from the Energy Materials and Surface Sciences Unit of the Okinawa Institute of Science and Technology Graduate University。
文摘Perovskite solar cells(PSCs)emerging as a promising photovoltaic technology with high efficiency and low manufacturing cost have attracted the attention from all over the world.Both the efficiency and stability of PSCs have increased steadily in recent years,and the research on reducing lead leakage and developing eco-friendly lead-free perovskites pushes forward the commercialization of PSCs step by step.This review summarizes the main progress of PSCs in 2020 and 2021 from the aspects of efficiency,stability,perovskite-based tandem devices,and lead-free PSCs.Moreover,a brief discussion on the development of PSC modules and its challenges toward practical application is provided.
基金supported by the National Natural Science Foundation of China(21875067,51811530011,11604099)the Fundamental Research Funds for the Central Universities,Shanghai Rising-Star(19QA1403100)+2 种基金ECNU Multifunctional Platform for Innovation(006)the National Key Research and Development Program of China(2017YFA0206600)the National Natural Science Foundation of China(51773045,21772030,51922032,21961160720)for financial support。
文摘Defect passivation is one of the most important strategies to boost both the efficiency and stability of perovskite solar cells(PSCs).Here,nontoxic and sustainable forest-based biomaterial,betulin,is first introduced into perovskites.The experiments and calculations reveal that betulin can effectively passivate the uncoordinated lead ions in perovskites via sharing the lone pair electrons of hydroxyl group,promoting charge transport.As a result,the power conversion efficiencies of the p-i-n planar PSCs remarkably increase from 19.14%to 21.15%,with the improvement of other parameters.The hydrogen bonds of betulin lock methylamine and halogen ions along the grain boundaries and on the film surface and thus suppress ion migration,further stabilizing perovskite crystal structures.These positive effects enable the PSCs to maintain 90%of the initial efficiency after 30 days in ambient air with 60%±5%relative humidity,75%after 300 h aging at 85℃,and 55%after 250 h light soaking,respectively.This work opens a new pathway for using nontoxic and low-cost biomaterials from forest to make highly efficient and stable PSCs.
基金supported by the National Science Foundation of China grant(21875067)the Fundamental Research Funds for the Central Universities,Shanghai Rising-Star(19QA1403100)+4 种基金East China Normal University(ECNU)Multifunctional Platform for InnovationThe Ministry of Science and Technology of the People’s Republic of China(No.2018YFF01012504)the National Key Research and Development Program of China(2017YFA0206600)the National Natural Science Foundation of China(51773045,21772030,51922032,21961160720)for financial support。
文摘Surface passivation via post-treatment is an important strategy for improving power conversion efficiency and operational stability of perovskite solar cells.However,so far the interaction mechanisms between passivating additive and perovskite are not well understood.Here,we report the atomic-scale interaction of surface passivating additive 2,2-difluoroethylammonium bromine(2FEABr)on the MAPbI_(3).It is found that the bulky 2FEA+cations tend to distribute at film surface,while the Br−anions diffuse from surface into bulk.A combination of 19F,207Pb,and 2H solid-state NMR further reveal the Br−anions’partial substitution for the I−sites,the restricted motion of partial MA+cations,and the firmed perovskite lattices,which would improve charge transport and stability of the perovskite films.Optical spectroscopy and ultraviolet photoelectron spectroscopy demonstrate that the 2FEABr induced surface passivation and energetic modification suppress the nonradiative recombination loss.These findings enable the efficiency of the p-i-n structured PSC significantly increasing from 19.44 to 21.06%,accompanied by excellent stability.Our work further establishes more knowledge link between passivating additive and PSC performance.
基金financially supported by the National Natural Science Foundation of China NSFC(51702038)the Recruitment Program for Young Professionals+1 种基金the National Key Research and Development Program of China(2017YFA0206600)the National Natural Science Foundation of China(51773045,21772030,51922032,21961160720)for financial support。
文摘Nickel oxide(NiOx)has exhibited great potential as an inorganic hole transport layer(HTL)in perovskite solar cells(PSCs)due to its wide optical bandgap and superior stability.In this study,we have modulated the Ni26 vacancies in NiOx film by controlling deposition temperature in a hot-casting process,resulting the change of coordination structure and charge state of NiOx.Moreover,the change of the HOMO level of NiOx makes it more compatible with perovskite to decrease energy losses and enhance hole carrier injection efficiency.Besides,the defect modulation in the electronic structure of NiOx is beneficial for increasing the electrical conductivity and mobility,which are considered to achieve the balance of charge carrier transport and avoid charge accumulation at the interface between perovskite and HTL effectively.Both experimental analyses and theoretical calculations reveal the increase of nickel vacancy defects change the electronic structure of NiOx by increasing the ratio of Ni3^+/Ni2^+-and improving the p-type characteristics.Accordingly,an optimal deposition temperature at 120℃enabled a 36.24%improvement in the power conversion efficiency compared to that deposited at room temperature(25℃).Therefore,this work provides a facile method to manipulate the electronic structure of NiOx to improve the charge carrier transport and photovoltaic performance of related PSCs.
基金funded by the National Natural Science Foundation of China (51902148, 61704099, 51801088 and 11664001)the Fundamental Research Funds for the Central Universities (lzujbky-2020-61, lzujbky-2019-88 and lzujbky-2020-kb06)the Special Funding for Open and Shared Large-Scale Instruments and Equipments of Lanzhou University (LZU-GXJJ-2019C023 and LZU-GXJJ-2019C019)。
文摘Perovskite materials have made a great progress in terms of the power conversion efficiency(PCE), rising from 3.8% to 25.2%. To obtain pinhole-free, superior crystal, and high-quality perovskite films with less defect, intermediates transformation is important, which has been clearly studied and widely applied.In this review, we systematically summarize the commonly formed intermediates and detailedly analyze their mechanisms from five aspects:(1) Solvent-induced intermediate;(2) HI-induced intermediate;(3)CH3NH2-induced intermediate;(4) MAAc-induced intermediate;(5) other intermediates. Finally, we also provide some prospects on high-quality perovskite fabrication based on using intermediates prudently.
基金supported by National Natural Science Foundation of China(No.21872080)National Key Research and Development Program of China(2022YFB3803304)+2 种基金supported by Tsinghua University Initiative Scientific Research Program(20221080065,20223080044)The State Key Laboratory of Power System and Generation Equipment(Nos.SKLD21Z03 and SKLD20M03)the Chinese Thousand Talents Program for Young Professionals.
文摘Perovskite solar cells(PSCs)have become the represent-atives of next generation of photovoltaics;nevertheless,their stability is insufficient for large scale deployment,particularly the reverse bias stability.Here,we propose a transparent conducting oxide(TCO)and low-cost metal composite electrode to improve the stability of PSCs without sacrificing the efficiency.The TCO can block ion migrations and chemical reactions between the metal and perovskite,while the metal greatly enhances the conductivity of the composite electrode.As a result,composite electrode-PSCs achieved a power conversion efficiency(PCE)of 23.7%(certified 23.2%)and exhibited excellent stability,maintaining 95%of the initial PCE when applying a reverse bias of 4.0 V for 60 s and over 92%of the initial PCE after 1000 h continuous light soaking.This composite electrode strategy can be extended to different combinations of TCOs and metals.It opens a new avenue for improving the stability of PSCs.
基金We thank the National Key Research and Development Program of China(2022YFB3803300)the open research fund of Songshan Lake Materials Laboratory(2021SLABFK02)+1 种基金the National Natural Science Foundation of China(21961160720 and 52203217)the China Postdoctoral Science Foundation(2021M690805)for financial support.
文摘After fast developing of single-junction perovskite solar cells and organic solar cells in the past 10 years,it is becoming harder and harder to improve their power conversion efficiencies.Tandem solar cells are receiving more and more attention because they have much higher theoretical efficiency than single-junction solar cells.Good device performance has been achieved for perovskite/silicon and perovskite/perovskite tandem solar cells,including 2-terminal and 4-terminal structures.However,very few studies have been done about 4-terminal inorganic perovskite/organic tandem solar cells.In this work,semi-transparent inorganic perovskite solar cells and organic solar cells are used to fabricate 4-terminal inorganic perovskite/organic tandem solar cells,achieving a power conversion efficiency of 21.25%for the tandem cells with spin-coated perovskite layer.By using drop-coating instead of spin-coating to make the inorganic perovskite films,4-terminal tandem cells with an efficiency of 22.34%are made.The efficiency is higher than the reported 2-terminal and 4-terminal inorganic perovskite/organic tandem solar cells.In addition,equivalent 2-terminal tandem solar cells were fabricated by connecting the sub-cells in series.The stability of organic solar cells under continuous illumination is improved by using semi-transparent perovskite solar cells as filter.
基金the National Key Research and Development Program of China(2022YFB3803300)the open research fund of Songshan Lake Materials Laboratory(2021SLABFK02)the National Natural Science Foundation of China(21961160720)。
文摘Polarization means symmetry loss for light vibration along light propagation direction,which is a particular physical property of light.The polarization state is indecipherable for most polarization-insensitive detectors.Polarization can carry and differentiate light information,and can be used in polarized light detection,polarization imaging and encryption communication[1].Photodetectors are the core component of some photoelectric devices[2]used in biomedical sensing,remote sensing,military field,etc.
基金financially supported by the National Key R&D Program of China(2018YFB1500105)the Natural Science Foundation of China(61874167)+3 种基金the Fundamental Research Funds for Central Universitiesthe 111 Project(B16027)the International Cooperation Base(2016D01025)the National Natural Science Foundation of China(51773045,21772030,51922032,21961160720)for financial support。
文摘Metal halide perovskite-based solar cells(PSCs) have rapidly-increased power conversion efficiency(PCE)exceeding 25% but poor stability especially under ultraviolet(UV) light. Meanwhile, non-radiative recombination caused by diverse defects in perovskite absorbers and related interfaces is one of the major factors confining further development of PSCs. In this study, we systematically investigate the role of 2-(2-hydroxy-5-methylphenyl)benzotriazole(UVP) additive in perovskite layers. By adjusting the amount of doped UVP, the quality of perovskite absorbers is significantly improved with enlarged grains, longer lifetime and diffusion length of charge carriers. Furthermore, UVP not only reduces defects for less nonradiative recombination, but also matches energy level alignment for efficient interfacial charge extraction. X-ray photoelectron spectroscopy confirms that N-donor of UVP molecule coordinates with undercoordinated Pb^(2+) on the surface. Interestingly, UVP incorporated in PbI_(2) protects the perovskite by absorbing UV through the opening and closing of the chelating ring. Eventually, the UVP treated PSCs obtain a champion PCE of 22.46% with remarkably enhanced UV stability, retaining over 90% of initial PCE after 60 m W/cm^(2) strong UV irradiation for 9 h while the control maintaining only 74%. These results demonstrate a promising strategy fabricating passivated and UV-resistant perovskite materials simultaneously for efficient and stable perovskite photovoltaics.
基金funded by the National Natural Science Foundation of China(51902148,61704099,51801088 and 51802024)the Fundamental Research Funds for the Central Universities(lzujbky2020-61,lzujbky-2019-88 and lzujbky-2020-kb06)the Special Funding for Open and Shared Large-Scale Instruments and Equipments of Lanzhou University(LZU-GXJJ-2019C023 and LZU-GXJJ-2019C019)。
文摘Recently,perovskite solar cells(PSCs) have flourished,and their power conversion efficiency(PCE) has increased from the initial 3.8% to 25.2% in 2019,which is an unprecedented advance.However,usually high-efficiency and stable PSCs are small-area devices prepared by spin coating.This method is not suitable for the preparation of large-area devices in commercialization.Therefore,there is an urgent need to develop new materials and methods for the scalable fabrication of PSCs.In this review,we first describe the common small-area PSCs preparation methods,understand the nucleation and crystal growth kinetics of perovskite,and analyze the reasons that hinder the development of small-area devices to large-area devices.Next,in order to meet the challenges of PSC’s scalable fabrication,we summarize and analyze four strategies:scaling up precursor solutions,scalable deposition methods for large-area films,scaling up charge-transport layers and back electrodes,developing solar modules.Finally,challenges and prospects are proposed to help researchers prepare high-efficiency large-area PSCs.
基金financially supported by the National Natural Science Foundation of China(Grants 21805114,21905119)Key Research and Development program of Jiangsu Province(BE2019009-2)+4 种基金Natural Science Foundation of Jiangsu province(BK20180869,BK20180867)China Postdoctoral Science Foundation(2019M651741),Top talents in Jiangsu province(XNY066)the Jiangsu University Foundation(17JDG032,17JDG031)Hightech Research Key laboratory of Zhenjiang(SS2018002)the State Key Laboratory of Fine Chemicals(KF1902)。
文摘Due to their excellent photoelectron chemical properties and suitable energy level alignment with perovskite,perylene diimide(PDI)derivatives are competitive non-fullerene electron transport material(ETM)candidates for perovskite solar cells(PSCs).However,the conjugated rigid plane structure of PDI units result in PDI-based ETMs tending to form large aggregates,limiting their application and photovoltaic performance.In this study,to restrict aggregation and further enhance the photovoltaic performance of PDI-type ETMs,two PDI-based ETMs,termed PDO-PDI2(dimer)and PDO-PDI3(trimer),were constructed by introducing a phenothiazine 5,5-dioxide(PDO)core building block.The research manifests that the optoelectronic properties and film formation property of PDO-PDI2 and PDO-PDI3 were deeply affected by the molecular spatial configuration.Applied in PSCs,PDO-PDI3 with threedimensional spiral molecular structure,exhibits superior electron extraction and transport properties,further achieving the best PCE of 18.72%and maintaining 93%of its initial efficiency after a 720-h aging test under ambient conditions.
基金the financial support from the Guangdong Basic and Applied Basic Research Foundation (2019A1515110770)National Key Research and Development Program of China (2017YFA0206600)National Natural Science Foundation of China (51773045, 21772030, 51922032, 21961160720) for financial support。
文摘Perovskite-based optoelectronic devices using organic–inorganic, metal halide, hybrid thin films have revolutionized the pathway towards constructing more efficient and stable photovoltaics and light-emitting electronics [1,2]. Nevertheless, solutionprocessed polycrystalline perovskite films inevitably contain a high density of crystallographic or ionic defects.
基金supported by the National Natural Science Foundation of China(61935016,62275213 and 62205264),the National Natural Science Foundation of China(21961160720)the Fundamental Research Funds for Xi'an Jiaotong University(xzy012022092,xzd012022003 and xzy022022057)+1 种基金the National Key Research and Development Program of China(2022YFB3803300)the open research fund of Songshan Lake Materials Laboratory(2021SLABFK02)。
文摘Perovskite solar cells(PSCs)have attracted aggressive attention in the photovoltaic field in light of the rapid increasing power conversion efficiency.However,their large-scale application and commercialization are limited by the toxicity issue of lead(Pb).Among all the lead-free perovskites,tin(Sn)-based perovskites have shown potential due to their low toxicity,ideal bandgap structure,high carrier mobility,and long hot carrier lifetime.Great progress of Sn-based PSCs has been realized in recent years,and the certified efficiency has now reached over 14%.Nevertheless,this record still falls far behind the theoretical calculations.This is likely due to the uncontrolled nucleation states and pronounced Sn(Ⅳ)vacancies.With insights into the methodologies resolving both issues,ligand engineering-assisted perovskite film fabrication dictates the state-of-the-art Sn-based PSCs.Herein,we summarize the role of ligand engineering during each state of film fabrication,ranging from the starting precursors to the ending fabricated bulks.The incorporation of ligands to suppress Sn~(2+)oxidation,passivate bulk defects,optimize crystal orientation,and improve stability is discussed,respectively.Finally,the remained challenges and perspectives toward advancing the performance of Sn-based PSCs are presented.We expect this review can draw a clear roadmap to facilitate Sn-based PSCs via ligand engineering.
基金financially supported by the National Natural Science Foundation of China(51702038)the Science&Technology Department of Sichuan Province(2020YFG0061)+2 种基金the Recruitment Program for Young Professionalsthe National Key Research and Development Program of China(2017YFA0206600)the National Natural Science Foundation of China(51773045,21772030,51922032,21961160720)for financial support。
文摘Tin halide perovskites(THPs)have received extensive attention due to their low toxicity and excellent optoelectronic properties,and are considered to be the most promising alternatives to develop efficient lead-free perovskite solar cells.However,due to the unique and inherent characteristics of Sn^(2+)being easily oxidized to Sn^(4+)and fast crystallization,tin perovskite solar cells(TPSCs)show relatively poor performance and stability,compared to the lead counterparts.Recently,the introduction of bulky organic spacers into three-dimensional(3D)THPs for dimensional regulation can not only prevent the intrusion of water and oxygen,but also inhibit the self-doping effect and ion migration.In this review,we will detail how dimensional regulation enables TPSCs with high performance and superior stability.First,we summarize the intrinsic properties of THPs and analyze the root causes of their poor performance and instability.Next,we discuss the specific structure and types of the dimensional regulation strategy.Then,the mechanism of dimensional regulation is discussed in detail,mainly from inhibiting the Sn^(2+)oxidation,optimizing crystallization,passivating defects,and improving energy level alignment.Finally,future challenges and prospects for dimensional regulation are elaborated to help researchers develop more efficient and stable TPSCs.
基金supported by National Natural Science Foundation of China(Grant No.52072327,62074052,61874159)Zhongyuan Thousand Talents(Zhongyuan Scholars)Program of Henan Province(202101510004)+6 种基金Higher Education and Teaching Reformation Project(2014SJGLX064)Academic Degrees&Graduate Education Reform Project of Henan Province(2021SJGLX060Y)Key research and development projects of Universities in Henan Province(20A140026)the Scientific Research Innovation Team of Xuchang University(2022CXTD008)Science and Technology Project of Henan Province(222102230009).L.Ding thanks the National Key Research and Development Program of China(2022YFB3803300)the open research fund of Songshan Lake Materials Laboratory(2021SLABFK02)the National Natural Science Foundation of China(21961160720).
文摘Lead-free inorganic copper-silver-bismuth-halide materials have attracted more and more attention due to their environmental friendliness,high element abundance,and low cost.Here,we developed a strategy of one-step gas-solid-phase diffusioninduced reaction to fabricate a series of bandgap-tunable Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI bilayer films due to the atomic diffusion effect for the first time.By designing and regulating the sputtered Cu/Ag/Bi metal film thickness,the bandgap of Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI could be reduced from 2.06 to 1.78 eV.Solar cells with the structure of FTO/TiO_(2)/Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI/carbon were constructed,yielding a champion power conversion efficiency of 2.76%,which is the highest reported for this class of materials owing to the bandgap reduction and the peculiar bilayer structure.The current work provides a practical path for developing the next generation of efficient,stable,and environmentally friendly photovoltaic materials.
基金financially supported by the National Natural Science Foundation of China NSFC (51702038)the Sichuan Science and Technology Program (2020YFG0061)+1 种基金the Recruitment Program for Young Professionals. L. Ding thanks National Key Research and Development Program of China (2017YFA0206600)National Natural Science Foundation of China (51773045, 21772030, 51922032, 21961160720) for financial support。
文摘Organic-inorganic metal halide perovskite solar cells(PSCs) have recently been considered as one of the most competitive contenders to commercial silicon solar cells in the photovoltaic field.The deposition process of a perovskite film is one of the most critical factors affecting the quality of the film formation and the photovoltaic performance.A hot-casting technique has been widely implemented to deposit high-quality perovskite films with large grain size,uniform thickness,and preferred crystalline orientation.In this review,we first review the classical nucleation and crystal growth theory and discuss those factors affecting the hot-casted perovskite film formation.Meanwhile,the effects of the deposition parameters such as temperature,thermal annealing,precursor chemistry,and atmosphere on the preparation of high-quality perovskite films and high-efficiency PSC devices are comprehensively discussed.The excellent stability of hot-casted perovskite films and integration with scalable deposition technology are conducive to the commercialization of PSCs.Finally,some open questions and future perspectives on the maturity of this technology toward the upscaling deposition of perovskite film for related optoelectronic devices are presented.
基金supported by the National Natural Science Foundation of China (51702038)National Natural Science Foundation of China (51773045, 21772030, 51922032, 21961160720) for financial support+1 种基金the Recruitment Program for Young ProfessionalsNational Key Research and Development Program of China (2017YFA0206600)。
文摘Perovskite quantum-dots (PQDs) have emerged as prominent candidates for intriguing photovoltaic application due to their superior optoelectronic properties such as multiple exciton generation, bandgap tunability, electronic and surface chemistry properties, as well as flexible composition [1–5].
基金the National Key Research and Development Program of China(2018YFE0204000)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB43000000)+5 种基金the National Natural Science Foundation of China(62274155,U20A20206,51972300 and 21975245)K.Liu thanks the Youth Innovation Promotion Association(CAS)(2020114)the Beijing Nova Program(2020117)L.Ding thanks the National Key Research and Development Program of China(2022YFB3803300)the open research fund of Songshan Lake Materials Laboratory(2021SLABFK02)the National Natural Science Foundation of China(21961160720).
文摘Tandem solar cells based on metal halide perovskites are advancing rapidly during last few years[1–17].The certified power conversion efficiency(PCE)for monolithic perovskite/silicon tandem solar cell reaches 32.5%[18].Since tandem solar cells contain more layers than single-junction solar cells,stress/strain control is an issue during fabrication and further practical operation.The stress can not only affect the stability of the perovskite layer but also change the optoelectronic properties of the films[19–23].
