Lead halide hybrid perovskites(LHP)have emerged as one of the most promising photovoltaic materials for their remarkable solar energy conversion ability.The transportation of the photoinduced carriers in LHP could scr...Lead halide hybrid perovskites(LHP)have emerged as one of the most promising photovoltaic materials for their remarkable solar energy conversion ability.The transportation of the photoinduced carriers in LHP could screen the defect recombination with the help of the large polaron formation.However,the physical insight of the relationship between the superior optical-electronic performance of perovskite and its polaron dynamics related to the electron-lattice strong coupling induced by the substitution engineering is still lack of investigation.Here,the bandgap modulated thin films ofα-FAPbI_(3)with different element substitution is investigated by the time resolved Terahertz spectroscopy.We find the polaron recombination dynamics could be prolonged in LHP with a relatively smaller bandgap,even though the formation of polaron will not be affected apparently.Intuitively,the large polaron mobility in(FAPb I_(3))0.95(MAPbI_(3))0.05thin film is~30%larger than that in(FAPb I_(3))0.85(MAPbBr_(3))0.15.The larger mobility in(FAPb I_(3))0.95(MAPb I_(3))0.05could be assigned to the slowing down of the carrier scattering time.Therefore,the physical origin of the higher carrier mobility in the(FAPb I_(3))0.95(MAPbI_(3))0.05should be related with the lattice distortion and enhanced electron–phonon coupling induced by the substitution.In addition,(FAPbI_(3))0.95(MAPbI_(3))0.05will lose fewer active carriers during the polaron cooling process than that in(FAPb I_(3))0.85(MAPbBr_(3)),indicating lower thermal dissipation in(FAPbI_(3))0.95(MAPbI_(3))0.05.Our results suggest that besides the smaller bandgap,the higher polaron mobility improved by the substitution engineering inα-FAPbI_(3)can also be an important factor for the high PCE of the black phaseα-FAPbI_(3)based solar cell devices.展开更多
Green hydrogen from electrolysis of water has attracted widespread attention as a renewable power source.Among several hydrogen production methods,it has become the most promising technology.However,there is no large-...Green hydrogen from electrolysis of water has attracted widespread attention as a renewable power source.Among several hydrogen production methods,it has become the most promising technology.However,there is no large-scale renewable hydrogen production system currently that can compete with conventional fossil fuel hydrogen production.Renewable energy electrocatalytic water splitting is an ideal production technology with environmental cleanliness protection and good hydrogen purity,which meet the requirements of future development.This review summarizes and introduces the current status of hydrogen production by water splitting from three aspects:electricity,catalyst and electrolyte.In particular,the present situation and the latest progress of the key sources of power,catalytic materials and electrolyzers for electrocatalytic water splitting are introduced.Finally,the problems of hydrogen generation from electrolytic water splitting and directions of next-generation green hydrogen in the future are discussed and outlooked.It is expected that this review will have an important impact on the field of hydrogen production from water.展开更多
In the exploration of next-generation high-energy–density batteries,lithium metal is regarded as an ideal candidate for anode materials.However,lithium metal batteries (LMBs) face challenges in practical applications...In the exploration of next-generation high-energy–density batteries,lithium metal is regarded as an ideal candidate for anode materials.However,lithium metal batteries (LMBs) face challenges in practical applications due to the risks associated with organic liquid electrolytes,among which their low flash points are one of the major safety concerns.The adoption of high flash point quasi-solid polymer electrolytes(QSPE) that is compatible with the lithium metal anode and high-voltage cathode is therefore a promising strategy for exploring high-performance and high-safety LMBs.Herein,we employed the in-situ polymerization of poly (epoxidized soya fatty acid Bu esters-isooctyl acrylate-ditrimethylolpropane tetraacrylate)(PEID) to gel the liquid electrolyte that formed a PEID-based QSPE (PEID-QSPE).The flash point of PEID-QSPE rises from 25 to 82℃ after gelation,contributing to enhanced safety of the battery at elevated temperatures,whereas the electrochemical window increases to 4.9 V.Moreover,the three-dimensional polymer framework of PEID-QSPE is validated to facilitate the uniform growth of the solid electrolyte interphase on the anode,thereby improving the cycling stability of the battery.By employing PEID-QSPE,the Li|LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2) cell achieved long-term cycling stability (Coulombic efficiency,99.8%;>200 cycles at 0.1 C) even with a high cathode loading (~5 mg cm^(-2)) and an ultrathin Li(~50μm).This electrolyte is expected to afford inspiring insights for the development of safe and long-term cyclability LMBs.展开更多
Background: Civilian explosion blast injury is more frequent in developing countries, including China. However, the incidence, casualties, and characteristics of such incidents in China are unknown.Methods: This is a ...Background: Civilian explosion blast injury is more frequent in developing countries, including China. However, the incidence, casualties, and characteristics of such incidents in China are unknown.Methods: This is a retrospective analysis of the State Administration of Work Safety database. Incidents during a period from January 1, 2000 to April 30, 2017 were included in the analysis. The explosions were classified based on the number of deaths into extraordinarily major, major, serious and ordinary type. Descriptive statistics was used to analyze the incidence and characteristics of the explosions. Correlation analysis was performed to examine the potential correlations among various variables.Results: Data base search identified a total of 2098 explosions from 2000 to 2017, with 29,579 casualties: 15,788 deaths(53.4%), 12,637 injured(42.7%) and 1154 missing(3.9%). Majority of the explosions were serious type(65.4%). The number of deaths(39.5%) was also highest with the serious type(P=0.006). The highest incidence was observed in the fourth quarter of the year(October to December), and at 9:00–11:00 am and 4:00–6:00 pm of the day. The explosions were most frequent in coal-producing provinces(Guizhou and Shanxi Province). Coal mine gas explosions resulted majority of the deaths(9620, 60.9%). The number of explosion accidents closely correlated with economic output(regional economy and national GDP growth rate)(r=–0.372, P=0.040;r=0.629, P=0.028).Conclusions: The incidence and civilian casualties due to explosions remain unacceptable in developing China. Measures that mitigate the risk factors are of urgently required.展开更多
Electrochemical reduction of CO_(2)(CO_(2)ER) to formate has been a promising route to produce value-added chemicals.Developing low-cost and efficient electrocatalysts with high product selectivity is still a grand ch...Electrochemical reduction of CO_(2)(CO_(2)ER) to formate has been a promising route to produce value-added chemicals.Developing low-cost and efficient electrocatalysts with high product selectivity is still a grand challenge.Herein,a novel Ni nanoparticles-anchored CNT coated by mesoporous carbon with yolk-shell structure (CNT/Ni@mC) catalysis was designed for CO_(2)ER.Ni nanoparticles were confined in the cavity between CNT and mesoporous carbon shell and the confined space can be controlled by tuning the amount of silica precursor.The mesoporous carbon shell and confined space are beneficial to charge transmission during CO_(2)ER.In contrast to previous studies,the CNT/Ni@mC catalyst presents selectivity toward formate rather than CO.Electrochemical in situ attenuated total reflection Fourier transform infrared spectroscopy measurements indicate the presence of a COO* intermediate that converts to formate under CO_(2)ER conditions.The well-defined structural feature of the confined space of the Ni-based catalyst for selective CO_(2)ER to formate may facilitate in-depth mechanistic understandings on structural factors that affect CO_(2)ER performance.展开更多
α-phase formamidinium lead triiodide(FAPbI_(3))has demonstrated extraordinary properties for near-infrared perovskite lightemitting diodes(NIR-PeLEDs).The vacuum processing technique has recently received increasing ...α-phase formamidinium lead triiodide(FAPbI_(3))has demonstrated extraordinary properties for near-infrared perovskite lightemitting diodes(NIR-PeLEDs).The vacuum processing technique has recently received increasing attention from industry and academia due to its solvent-free feature and compatibility with large-scale production.Nevertheless,vacuum-deposited NIR-PeLEDs have been less studied,and their efficiencies lag far behind those of solution-based PeLEDs as it is still challenging to prepare pureα-FAPbI_(3)by the thermal evaporation.Herein,we report a Cs-containing triple-source co-evaporation approach to develop the perovskite films.The addition of thermally stable Cs cation fills in the perovskite crystal lattice and eliminates the formation of metallic Pb caused by the degradation of FA cation during the evaporation process.The tri-source co-evaporation strategy significantly promotes the phase transition from yellowδ-phase FAPbI_(3)to blackα-phase FACsPbI_(3),fostering smooth,uniform,and pinhole-free perovskite films with higher crystallinity and fewer defects.On this basis,the resulting NIR-PeLED based on FACsPbI_(3)yields a maximum EQE of 10.25%,which is around sixfold higher than that of FAPbI_(3)-based PeLEDs.Our work demonstrates a reliable and effective strategy to achieveα-FAPbI_(3)via thermal evaporation and paves the pathway toward highly efficient perovskite optoelectronic devices for future commercialization.展开更多
基金supported by the National Natural Science Foundation of China(Nos.92050203,61905264,61925507,61875211,61674023,62005296,and 62105347)the National Key R&D Program of China 2017YFE0123700+1 种基金Shanghai Pilot Program for Basic Research(22JC1403200)the CAS Interdisciplinary Innovation Team。
文摘Lead halide hybrid perovskites(LHP)have emerged as one of the most promising photovoltaic materials for their remarkable solar energy conversion ability.The transportation of the photoinduced carriers in LHP could screen the defect recombination with the help of the large polaron formation.However,the physical insight of the relationship between the superior optical-electronic performance of perovskite and its polaron dynamics related to the electron-lattice strong coupling induced by the substitution engineering is still lack of investigation.Here,the bandgap modulated thin films ofα-FAPbI_(3)with different element substitution is investigated by the time resolved Terahertz spectroscopy.We find the polaron recombination dynamics could be prolonged in LHP with a relatively smaller bandgap,even though the formation of polaron will not be affected apparently.Intuitively,the large polaron mobility in(FAPb I_(3))0.95(MAPbI_(3))0.05thin film is~30%larger than that in(FAPb I_(3))0.85(MAPbBr_(3))0.15.The larger mobility in(FAPb I_(3))0.95(MAPb I_(3))0.05could be assigned to the slowing down of the carrier scattering time.Therefore,the physical origin of the higher carrier mobility in the(FAPb I_(3))0.95(MAPbI_(3))0.05should be related with the lattice distortion and enhanced electron–phonon coupling induced by the substitution.In addition,(FAPbI_(3))0.95(MAPbI_(3))0.05will lose fewer active carriers during the polaron cooling process than that in(FAPb I_(3))0.85(MAPbBr_(3)),indicating lower thermal dissipation in(FAPbI_(3))0.95(MAPbI_(3))0.05.Our results suggest that besides the smaller bandgap,the higher polaron mobility improved by the substitution engineering inα-FAPbI_(3)can also be an important factor for the high PCE of the black phaseα-FAPbI_(3)based solar cell devices.
基金supported by the National Natural Science Foundation of China(U23A20573,U23A20140,22109038)the Starting Research Funds of Hebei University of Science and Technology,Hebei Natural Science Foundation(D2022208001)+1 种基金the S&T Program of Hebei(23314401D)Hebei Pharmaceutical and Chemical Technology Innovation Center(225676121H).
文摘Green hydrogen from electrolysis of water has attracted widespread attention as a renewable power source.Among several hydrogen production methods,it has become the most promising technology.However,there is no large-scale renewable hydrogen production system currently that can compete with conventional fossil fuel hydrogen production.Renewable energy electrocatalytic water splitting is an ideal production technology with environmental cleanliness protection and good hydrogen purity,which meet the requirements of future development.This review summarizes and introduces the current status of hydrogen production by water splitting from three aspects:electricity,catalyst and electrolyte.In particular,the present situation and the latest progress of the key sources of power,catalytic materials and electrolyzers for electrocatalytic water splitting are introduced.Finally,the problems of hydrogen generation from electrolytic water splitting and directions of next-generation green hydrogen in the future are discussed and outlooked.It is expected that this review will have an important impact on the field of hydrogen production from water.
基金the S&T Program of Hebei (Grant Nos. 22344402D,22373709D)the National Natural Science Foundation of China(Grant Nos. 22108151, 22108202, 22109084, 22209010,22379014, and 22309101)+3 种基金the Beijing Natural Science Foundation(Grant Nos. Z200011, L233004)the Young Elite Scientists Sponsorship Program by CAST (Grant No. 2021QNRC001)the Seed Fund of Shanxi Research Institute for Clean Energythe support from the Department of Science and Technology of Jilin Province (Grant No. 20210301021GX)。
文摘In the exploration of next-generation high-energy–density batteries,lithium metal is regarded as an ideal candidate for anode materials.However,lithium metal batteries (LMBs) face challenges in practical applications due to the risks associated with organic liquid electrolytes,among which their low flash points are one of the major safety concerns.The adoption of high flash point quasi-solid polymer electrolytes(QSPE) that is compatible with the lithium metal anode and high-voltage cathode is therefore a promising strategy for exploring high-performance and high-safety LMBs.Herein,we employed the in-situ polymerization of poly (epoxidized soya fatty acid Bu esters-isooctyl acrylate-ditrimethylolpropane tetraacrylate)(PEID) to gel the liquid electrolyte that formed a PEID-based QSPE (PEID-QSPE).The flash point of PEID-QSPE rises from 25 to 82℃ after gelation,contributing to enhanced safety of the battery at elevated temperatures,whereas the electrochemical window increases to 4.9 V.Moreover,the three-dimensional polymer framework of PEID-QSPE is validated to facilitate the uniform growth of the solid electrolyte interphase on the anode,thereby improving the cycling stability of the battery.By employing PEID-QSPE,the Li|LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2) cell achieved long-term cycling stability (Coulombic efficiency,99.8%;>200 cycles at 0.1 C) even with a high cathode loading (~5 mg cm^(-2)) and an ultrathin Li(~50μm).This electrolyte is expected to afford inspiring insights for the development of safe and long-term cyclability LMBs.
基金supported by Major State Research Projects (613307)Army Medical Center Talent Innovation Ability Training Program (2019CXJSB007)+1 种基金Thirteenth Five-Year"Double"Construction Research and Innovation Project of PLA (2019)Medical Research Funding of PLA (ASW14C003)。
文摘Background: Civilian explosion blast injury is more frequent in developing countries, including China. However, the incidence, casualties, and characteristics of such incidents in China are unknown.Methods: This is a retrospective analysis of the State Administration of Work Safety database. Incidents during a period from January 1, 2000 to April 30, 2017 were included in the analysis. The explosions were classified based on the number of deaths into extraordinarily major, major, serious and ordinary type. Descriptive statistics was used to analyze the incidence and characteristics of the explosions. Correlation analysis was performed to examine the potential correlations among various variables.Results: Data base search identified a total of 2098 explosions from 2000 to 2017, with 29,579 casualties: 15,788 deaths(53.4%), 12,637 injured(42.7%) and 1154 missing(3.9%). Majority of the explosions were serious type(65.4%). The number of deaths(39.5%) was also highest with the serious type(P=0.006). The highest incidence was observed in the fourth quarter of the year(October to December), and at 9:00–11:00 am and 4:00–6:00 pm of the day. The explosions were most frequent in coal-producing provinces(Guizhou and Shanxi Province). Coal mine gas explosions resulted majority of the deaths(9620, 60.9%). The number of explosion accidents closely correlated with economic output(regional economy and national GDP growth rate)(r=–0.372, P=0.040;r=0.629, P=0.028).Conclusions: The incidence and civilian casualties due to explosions remain unacceptable in developing China. Measures that mitigate the risk factors are of urgently required.
基金the Natural Science Foundation of Hebei(B02020208088,H_(2)020206514)the S&T Program of Hebei(20544401D,20314401D,206Z4406G,21314402D,B2021208074,21344601D)the Tianjin Science and Technology Project(19YFSLQY00070)。
文摘Electrochemical reduction of CO_(2)(CO_(2)ER) to formate has been a promising route to produce value-added chemicals.Developing low-cost and efficient electrocatalysts with high product selectivity is still a grand challenge.Herein,a novel Ni nanoparticles-anchored CNT coated by mesoporous carbon with yolk-shell structure (CNT/Ni@mC) catalysis was designed for CO_(2)ER.Ni nanoparticles were confined in the cavity between CNT and mesoporous carbon shell and the confined space can be controlled by tuning the amount of silica precursor.The mesoporous carbon shell and confined space are beneficial to charge transmission during CO_(2)ER.In contrast to previous studies,the CNT/Ni@mC catalyst presents selectivity toward formate rather than CO.Electrochemical in situ attenuated total reflection Fourier transform infrared spectroscopy measurements indicate the presence of a COO* intermediate that converts to formate under CO_(2)ER conditions.The well-defined structural feature of the confined space of the Ni-based catalyst for selective CO_(2)ER to formate may facilitate in-depth mechanistic understandings on structural factors that affect CO_(2)ER performance.
基金supported by the“Pioneer”and“Leading Goose”R&D Program of Zhejiang(2024C01192)National Natural Science Foundation of China(62322505,62425502,62375276,62375060,U23A6002,62050039,62004075,and 62374069)+1 种基金Shanghai Pilot Program for Basic Research(22JC1403200)the Natural Science Foundation of Hubei Province(2024AFB423).
文摘α-phase formamidinium lead triiodide(FAPbI_(3))has demonstrated extraordinary properties for near-infrared perovskite lightemitting diodes(NIR-PeLEDs).The vacuum processing technique has recently received increasing attention from industry and academia due to its solvent-free feature and compatibility with large-scale production.Nevertheless,vacuum-deposited NIR-PeLEDs have been less studied,and their efficiencies lag far behind those of solution-based PeLEDs as it is still challenging to prepare pureα-FAPbI_(3)by the thermal evaporation.Herein,we report a Cs-containing triple-source co-evaporation approach to develop the perovskite films.The addition of thermally stable Cs cation fills in the perovskite crystal lattice and eliminates the formation of metallic Pb caused by the degradation of FA cation during the evaporation process.The tri-source co-evaporation strategy significantly promotes the phase transition from yellowδ-phase FAPbI_(3)to blackα-phase FACsPbI_(3),fostering smooth,uniform,and pinhole-free perovskite films with higher crystallinity and fewer defects.On this basis,the resulting NIR-PeLED based on FACsPbI_(3)yields a maximum EQE of 10.25%,which is around sixfold higher than that of FAPbI_(3)-based PeLEDs.Our work demonstrates a reliable and effective strategy to achieveα-FAPbI_(3)via thermal evaporation and paves the pathway toward highly efficient perovskite optoelectronic devices for future commercialization.
