High-performance flexible one-dimensional(1D)electrochemical energy storage devices are crucial for the applications of wearable electronics.Although much progress on various 1D energy storage devices has been made,ch...High-performance flexible one-dimensional(1D)electrochemical energy storage devices are crucial for the applications of wearable electronics.Although much progress on various 1D energy storage devices has been made,challenges involving fabrication cost,scalability,and efficiency remain.Herein,a highperformance flexible all-fiber zinc-ion battery(ZIB)is fabricated using a low-cost,scalable,and efficient continuous wet-spinning method.Viscous composite inks containing cellulose nanofibers/carbon nanotubes(CNFs/CNTs)binary composite network and either manganese dioxide nanowires(MnO_(2) NWs)or commercial Zn powders are utilized to spinning fiber cathodes and anodes,respectively.MnO_(2) NWs and Zn powders are uniformly dispersed in the interpenetrated CNFs/CNTs fibrous network,leading to homogenous composite inks with an ideal shear-thinning property.The obtained fiber electrodes demonstrate favorable uniformity and flexibility.Benefiting from the well-designed electrodes,the assembled flexible fiber-shaped ZIB delivers a high specific capacity of 281.5 m Ah g^(-1) at 0.25 A g^(-1) and displays excellent cycling stability over 400 cycles.Moreover,the wet-spun fiber-shaped ZIBs achieve ultrahigh gravimetric and volumetric energy densities of 47.3 Wh kg^(-1) and 131.3 m Wh cm^(-3),respectively,based on both cathode and anode and maintain favorable stability even after 4000 bending cycles.This work offers a new concept design of 1D flexible ZIBs that can be potentially incorporated into commercial textiles for wearable and portable electronics.展开更多
Electrochemical catalysts for oxygen evolution reaction are a critical component for many renewable energy applications. To improve their catalytic kinetics and mass activity are essential for sustainable industrial a...Electrochemical catalysts for oxygen evolution reaction are a critical component for many renewable energy applications. To improve their catalytic kinetics and mass activity are essential for sustainable industrial applications. Here, we report a rare-earth metal-based oxide electrocatalyst comprised of ultrathin amorphous La2O3 nanosheets hybridized with uniform La2O3 nanoparticles(La2O3@NP-NS). Significantly improved OER performance is observed from the nanosheets with a nanometer-scale thickness. The as-synthesized 2.27-nm La2O3@NP-NS exhibits excellent catalytic kinetics with an overpotential of 310 mV at 10 m A cm^-2, a small Tafel slope of 43.1 mV dec^-1, and electrochemical impedance of 38 Ω. More importantly, due to the ultrasmall thickness, its mass activity, and turnover frequency reach as high as 6666.7 A g^-1 and 5.79 s^-1, respectively, at an overpotential of 310 mV. Such a high mass activity is more than three orders of magnitude higher than benchmark OER electrocatalysts, such as IrO2 and RuO2. This work presents a sustainable approach toward the development of highly e cient electrocatalysts with largely reduced mass loading of precious elements.展开更多
The triple cation mixed perovskites(Cs FAMA)are known as one of the most efficient candidates for perovskite solar cells(PSCs).It is found that the power conversion efficiency(PCE)of triple-cation based devices would ...The triple cation mixed perovskites(Cs FAMA)are known as one of the most efficient candidates for perovskite solar cells(PSCs).It is found that the power conversion efficiency(PCE)of triple-cation based devices would increase with the test time extending,and the maximum efficiency is normally obtained after several days aging storage.Here,the relationship between enhanced device performance,excess PbI_(2)and its evolution in triple cation perovskite films of initial days was systematically explored.The Cs FAMA-PSCs are prepared by two-step methods under two environmental conditions,including in the glove box and the ambient air(30%humidity).After 7 days testing,the maximum PCE of PSCs under two conditions dramatically increased 12.4%and 12.2%,reached 21.68%and 21.89%,respectively.At initial days,the XRD peak intensities of perovskite phase gradually decreased and those corresponding to PbI_(2)increased.Along with time-resolved photoluminescence(TRPL)and kelvin probe force microscopy(KPFM),it was found that the defects were passivated with the evolution of PbI_(2).This work reveals the excess PbI_(2)and its evolution in perovskite film,which can further supplement the understanding of PbI_(2)defect passivation.展开更多
基金financially supported by the National Science Fund for Distinguished Young Scholars(52025133)the Beijing Natural Science Foundation(JQ18005)+7 种基金the Tencent Foundation through the XPLORER PRIZE,the National Key R&D Program of China(2017YFA0206701)the BIC-ESAT fundingthe financial support of the Central Universities(2232020D-13)the Shanghai Sailing Program(20YF1400700)the National Natural Science Foundation of China(52003045)the financial support from the Young Elite Scientist Sponsorship Program by CAST(2019QNRC001)the“1000-Plan program”of Shaanxi Provincethe“Young Talent Support Plan”of Xi’an Jiaotong University。
文摘High-performance flexible one-dimensional(1D)electrochemical energy storage devices are crucial for the applications of wearable electronics.Although much progress on various 1D energy storage devices has been made,challenges involving fabrication cost,scalability,and efficiency remain.Herein,a highperformance flexible all-fiber zinc-ion battery(ZIB)is fabricated using a low-cost,scalable,and efficient continuous wet-spinning method.Viscous composite inks containing cellulose nanofibers/carbon nanotubes(CNFs/CNTs)binary composite network and either manganese dioxide nanowires(MnO_(2) NWs)or commercial Zn powders are utilized to spinning fiber cathodes and anodes,respectively.MnO_(2) NWs and Zn powders are uniformly dispersed in the interpenetrated CNFs/CNTs fibrous network,leading to homogenous composite inks with an ideal shear-thinning property.The obtained fiber electrodes demonstrate favorable uniformity and flexibility.Benefiting from the well-designed electrodes,the assembled flexible fiber-shaped ZIB delivers a high specific capacity of 281.5 m Ah g^(-1) at 0.25 A g^(-1) and displays excellent cycling stability over 400 cycles.Moreover,the wet-spun fiber-shaped ZIBs achieve ultrahigh gravimetric and volumetric energy densities of 47.3 Wh kg^(-1) and 131.3 m Wh cm^(-3),respectively,based on both cathode and anode and maintain favorable stability even after 4000 bending cycles.This work offers a new concept design of 1D flexible ZIBs that can be potentially incorporated into commercial textiles for wearable and portable electronics.
基金supported by Army Research O ce(ARO)under Grant W911NF-16-1-0198the National Science Foundation(DMR-1709025)China Scholarship Council
文摘Electrochemical catalysts for oxygen evolution reaction are a critical component for many renewable energy applications. To improve their catalytic kinetics and mass activity are essential for sustainable industrial applications. Here, we report a rare-earth metal-based oxide electrocatalyst comprised of ultrathin amorphous La2O3 nanosheets hybridized with uniform La2O3 nanoparticles(La2O3@NP-NS). Significantly improved OER performance is observed from the nanosheets with a nanometer-scale thickness. The as-synthesized 2.27-nm La2O3@NP-NS exhibits excellent catalytic kinetics with an overpotential of 310 mV at 10 m A cm^-2, a small Tafel slope of 43.1 mV dec^-1, and electrochemical impedance of 38 Ω. More importantly, due to the ultrasmall thickness, its mass activity, and turnover frequency reach as high as 6666.7 A g^-1 and 5.79 s^-1, respectively, at an overpotential of 310 mV. Such a high mass activity is more than three orders of magnitude higher than benchmark OER electrocatalysts, such as IrO2 and RuO2. This work presents a sustainable approach toward the development of highly e cient electrocatalysts with largely reduced mass loading of precious elements.
基金the financial support from the Young Scholars Development Fund of SWPU(201699010017)the Sichuan Science and Technology Program(2018JY0015)+1 种基金the National Nature Science Foundation of China(61774022)the 2020 Li Ka Shing Foundation Cross-Disciplinary Research Grant(2020LKSFG01A)。
文摘The triple cation mixed perovskites(Cs FAMA)are known as one of the most efficient candidates for perovskite solar cells(PSCs).It is found that the power conversion efficiency(PCE)of triple-cation based devices would increase with the test time extending,and the maximum efficiency is normally obtained after several days aging storage.Here,the relationship between enhanced device performance,excess PbI_(2)and its evolution in triple cation perovskite films of initial days was systematically explored.The Cs FAMA-PSCs are prepared by two-step methods under two environmental conditions,including in the glove box and the ambient air(30%humidity).After 7 days testing,the maximum PCE of PSCs under two conditions dramatically increased 12.4%and 12.2%,reached 21.68%and 21.89%,respectively.At initial days,the XRD peak intensities of perovskite phase gradually decreased and those corresponding to PbI_(2)increased.Along with time-resolved photoluminescence(TRPL)and kelvin probe force microscopy(KPFM),it was found that the defects were passivated with the evolution of PbI_(2).This work reveals the excess PbI_(2)and its evolution in perovskite film,which can further supplement the understanding of PbI_(2)defect passivation.
