Over the last decade,remarkable progress has been made in metal halide perovskite solar cells(PSCs),which have been a focus of emerging photovoltaic techniques and show great potential for commercialization.However,th...Over the last decade,remarkable progress has been made in metal halide perovskite solar cells(PSCs),which have been a focus of emerging photovoltaic techniques and show great potential for commercialization.However,the upscaling of small-area PSCs to large-area solar modules to meet the demands of practical applications remains a significant challenge.The scalable production of high-quality perovskite films by a simple,reproducible process is crucial for resolving this issue.Furthermore,the crystallization behavior in the solution-processed fabrication of perovskite films can be strongly influenced by the physicochemical properties of the precursor inks,which are significantly affected by the employed solvents and their interactions with the solutes.Thus,a comprehensive understanding of solvent engineering for fabricating perovskite films over large areas is urgently required.In this paper,we first analyze the role of solvents in the solution-processed fabrication of large-area perovskite films based on the classical crystal nucleation and growth mechanism.Recent efforts in solvent engineering to improve the quality of perovskite films for solar modules are discussed.Finally,the basic principles and future challenges of solvent system design for scalable fabrication of high-quality perovskite films for efficient solar modules are proposed.展开更多
Researchers working in the field of photovoltaic are exploring novel materials for the efficient solar energy conversion.The prime objective of the discovery of every novel photovoltaic material is to achieve more ene...Researchers working in the field of photovoltaic are exploring novel materials for the efficient solar energy conversion.The prime objective of the discovery of every novel photovoltaic material is to achieve more energy yield with easy fabrication process and less production cost features.Perovskite solar cells (PSCs)delivering the highest efficiency in the passing years with different stoichiometry and fabrication modification have made this technology a potent candidate for future energy conversion materials.Till now,many studies have shown that the quality of active layer morphology,to a great extent,determines the performance of PSCs.The current and potential techniques of solvent engineering for good active layer morphology are mainly debated using primary solvent,co-solvent (Lewis acid-base adduct approach)and solvent additives.In this review,the dynamics of numerously reported solvents on the morphological characteristics of PSCs active layer are discussed in detail.The intention is to get a clear understanding of solvent engineering induced modifications on active layer morphology in PSC devices via different crystallization routes.At last,an attempt is made to draw a framework based on different solvent coordination properties to make it easy for screening the potent solvent contender for desired PSCs precursor for a better and feasible device.展开更多
The inherent evolvability of promiscuous enzymes endows them with great potential to be artificially evolved for novel functions.Previously,we succeeded in transforming a promiscuous acylaminoacyl peptidase(apAAP)from...The inherent evolvability of promiscuous enzymes endows them with great potential to be artificially evolved for novel functions.Previously,we succeeded in transforming a promiscuous acylaminoacyl peptidase(apAAP)from the hyperthermophilic archaeon Aeropyrum pernix K1 into a specific carboxylesterase by making a single mutation.In order to fulfill the urgent requirement of thermostable lipolytic enzymes,in this paper we describe how the substrate preference of apAAP can be further changed from p-nitrophenyl caprylate(pNP-C8)to p-nitrophenyl laurate(pNP-C12)by protein and solvent engineering.After one round of directed evolution and subsequent saturation mutagenesis at selected residues in the active site,three variants with enhanced activity towards pNP-C12 were identified.Additionally,a combined mutant W474V/F488G/R526V/T560W was generated,which had the highest catalytic efficiency(kcat/Km)for pNP-C12,about 71-fold higher than the wild type.Its activity was further increased by solvent engineering,resulting in an activity enhancement of 280-fold compared with the wild type in the presence of 30%DMSO.The structural basis for the improved activity was studied by substrate docking and molecular dynamics simulation.It was revealed that W474V and F488G mutations caused a significant change in the geometry of the active center,which may facilitate binding and subsequent hydrolysis of bulky substrates.In conclusion,the combination of protein and solvent engineering may be an effective approach to improve the activities of promiscuous enzymes and could be used to create naturally rare hyperthermophilic enzymes.展开更多
Due to their unique photoelectric properties,nontoxic tin-based perovskites are emerging candidates for efficient near-infrared LEDs.However,the facile oxidation of Sn2+and the rapid crystallization rate of tin-based ...Due to their unique photoelectric properties,nontoxic tin-based perovskites are emerging candidates for efficient near-infrared LEDs.However,the facile oxidation of Sn2+and the rapid crystallization rate of tin-based perovskites result in suboptimal film quality,leading to inferior efficiencies of tin-based perovskite light-emitting diodes(Pero-LEDs).In this study,we investigate the influence of commonly used solvents on the quality of the CsSnI3 films.Remarkably,DMSO exhibits a stronger interaction with SnI2,forming a stable intermediate phase of SnI2·3DMSO.This intermediate effectively inhibits the oxidation of Sn2+and slows down the crystallization rate,bringing in lower defect state density and higher photoluminescence quantum yield of the pre-pared perovskite films.Consequently,the corresponding Pero-LEDs achieve a maximum external quantum efficiency(EQE)of 5.6%,among the most effi-cient near-infrared Pero-LEDs.In addition,the device processes ultra-low effi-ciency roll-off and high reproducibility.Our research underscores the crucial role of solvent-perovskite coordination in determining film quality.These find-ings offer valuable guidance for screening solvents to prepare highly efficient and stable tin-based perovskites.展开更多
The use of non-halogenated solvents for the green manufacture of high-efficiency organic solar cells(OSCs)is important for their future application.However,the power conversion efficiency(PCE)of the non-halogenated so...The use of non-halogenated solvents for the green manufacture of high-efficiency organic solar cells(OSCs)is important for their future application.However,the power conversion efficiency(PCE)of the non-halogenated solvent processed OSCs is generally lower than their halogenated counterpart due to the poor film microstructure caused by the solubility issue.Herein,we propose a halogen-free solvent system to optimize film microstructure of the photovoltaic blend based on the polymer donor D18and small-molecule acceptor(SMA)L8-BO towards high-efficiency OSCs.The solvent system is consisted of a main solvent carbon disulfide and an additive paraxylene,where the former ensures the good solution-processability and promotes the solution aggregation of L8-BO,and the latter can finely control the phase-separation process by selectively dissolving the SMA.This solvent combination robustly produces a high-quality active layer,i.e.,the bicontinuous networks of donor and acceptor with nano-sized phase-separation and strongπ-πstacking.With the effective charge generation,transport and collection,the resulting device from the non-halogenated solvent system shows a high PCE of 17.50%,which is comparable to that of the device prepared from the halogenated solvent chloroform(ca.17.11%).This article proposes a new strategy for the green fabrication of high-efficiency OSCs to accelerate their industrialization.展开更多
Owing to its superior efficiency and low cost,the solution-processable perovskite has rapidly become the latest favorite material in the field of photovoltaics.Although solution processing significantly reduces the th...Owing to its superior efficiency and low cost,the solution-processable perovskite has rapidly become the latest favorite material in the field of photovoltaics.Although solution processing significantly reduces the threshold and cost of perovskite solar cells,the intricate composition and nonequilibrium nucleation of the perovskite precursor can result in leaky film.The precise control of perovskite nucleation and orientation is a fundamental prerequisite for achieving high-quality perovskite photoactive layers.In this process,the intermediate species that widely exists either in the precursor or the asprepared film acts as a transitional state for perovskite nucleation and growth from solution to solid,presenting an opportunity for controlling perovskite crystallization.Herein,we present an overview of the advancements in intermediates for solution-processing perovskite films to gain insights into the growth and manipulation of polycrystalline perovskite films.展开更多
Infrared solar cells are more efective than normal bandgap solar cells at reducing the spectral loss in the near-infrared region,thus also at broadening the absorption spectra and improving power conversion efciency.P...Infrared solar cells are more efective than normal bandgap solar cells at reducing the spectral loss in the near-infrared region,thus also at broadening the absorption spectra and improving power conversion efciency.PbS colloidal quantum dots(QDs)with tunable bandgap are ideal infrared photovoltaic materials.However,QD solar cell production sufers from small-areabased spin-coating fabrication methods and unstable QD ink.Herein,the QD ink stability mechanism was fully investigated according to Lewis acid–base theory and colloid stability theory.We further studied a mixed solvent system using dimethylformamide and butylamine,compatible with the scalable manufacture of method-blade coating.Based on the ink system,100 cm2 of uniform and dense near-infrared PbS QDs(~0.96 eV)flm was successfully prepared by blade coating.The average efciencies of above absorber-based devices reached 11.14%under AM1.5G illumination,and the 800 nm-fltered efciency achieved 4.28%.Both were the top values among blade coating method based devices.The newly developed ink showed excellent stability,and the device performance based on the ink stored for 7 h was similar to that of fresh ink.The matched solvent system for stable PbS QD ink represents a crucial step toward large area blade coating photoelectric devices.展开更多
Inorganic lead halide perovskite CsPbBr3 offers attractive photophysical properties and phase stability for high-performance optoelectronic devices.However,CsPbBr3 films produced by the classic solution-based two-step...Inorganic lead halide perovskite CsPbBr3 offers attractive photophysical properties and phase stability for high-performance optoelectronic devices.However,CsPbBr3 films produced by the classic solution-based two-step method are always accompanied with impurity phases of CsPb2Br5 and Cs4PbBr6,which represents a major efficiency-limiting factor for future advances of CsPbBr3-based devices.The challenge lies in the complexity of the Cs-Pb-Br phase system,requiring both spatially and temporally precise control of the precursor stoichiometry during solution-phase growth of CsPbBr3 films.By adopting 2-methoxyethanol as the solution conversion medium instead of commonly applied methanol,the reaction between CsBr and PbBr2 can be finely controlled to yield single phase CsPbBr3 films within a few minutes;extending the solution-conversion step to 24 h does not alter the phase purity of resulting CsPbBr3 films.The present work paves the way to regulate the crystal growth behaviors of two-step solution-processed CsPbBr3 films by simple solvent engineering.展开更多
An efficient panchromatic planar perovskite solar cell is developed based on highly uniform,lead-reduced CH3NH3Sn0.5Pb0.5I3 perovskite films with full film-coverage on the substrates.We demonstrate here that full-cove...An efficient panchromatic planar perovskite solar cell is developed based on highly uniform,lead-reduced CH3NH3Sn0.5Pb0.5I3 perovskite films with full film-coverage on the substrates.We demonstrate here that full-coverage of the CH3NH3Sn0.5Pb0.5I3 films can be developed by a facile chlorobenzene-assisted spin-coating method.A power conversion efficiency of 7 % is achieved using low-temperature processes,which is among the best-reported performance for panchromatic planar perovskite solar cells with a light-absorption over 1,000 nm.展开更多
基金financially supported by the National Key Research and Development Project funding from the Ministry of Science and Technology of China(2021YFB3800104)the National Natural Science Foundation of China(51822203,52002140,U20A20252,51861145404,62105293,62205187)+4 种基金the Young Elite Scientists Sponsorship Program by CAST,the Self-determined and Innovative Research Funds of HUST(2020KFYXJJS008)the Natural Science Foundation of Hubei Province(ZRJQ2022000408)the Shenzhen Science and Technology Innovation Committee(JCYJ20180507182257563)Fundamental Research Program of Shanxi Province(202103021223032)the Innovation Project of Optics Valley Laboratory of China(OVL2021BG008)。
文摘Over the last decade,remarkable progress has been made in metal halide perovskite solar cells(PSCs),which have been a focus of emerging photovoltaic techniques and show great potential for commercialization.However,the upscaling of small-area PSCs to large-area solar modules to meet the demands of practical applications remains a significant challenge.The scalable production of high-quality perovskite films by a simple,reproducible process is crucial for resolving this issue.Furthermore,the crystallization behavior in the solution-processed fabrication of perovskite films can be strongly influenced by the physicochemical properties of the precursor inks,which are significantly affected by the employed solvents and their interactions with the solutes.Thus,a comprehensive understanding of solvent engineering for fabricating perovskite films over large areas is urgently required.In this paper,we first analyze the role of solvents in the solution-processed fabrication of large-area perovskite films based on the classical crystal nucleation and growth mechanism.Recent efforts in solvent engineering to improve the quality of perovskite films for solar modules are discussed.Finally,the basic principles and future challenges of solvent system design for scalable fabrication of high-quality perovskite films for efficient solar modules are proposed.
基金supported by the National Key Research and Development Program of China (2016YFA0202400)the 111 project (B16016)the National Natural Science Foundation of China (51572080, 51702096, and U1705256)
文摘Researchers working in the field of photovoltaic are exploring novel materials for the efficient solar energy conversion.The prime objective of the discovery of every novel photovoltaic material is to achieve more energy yield with easy fabrication process and less production cost features.Perovskite solar cells (PSCs)delivering the highest efficiency in the passing years with different stoichiometry and fabrication modification have made this technology a potent candidate for future energy conversion materials.Till now,many studies have shown that the quality of active layer morphology,to a great extent,determines the performance of PSCs.The current and potential techniques of solvent engineering for good active layer morphology are mainly debated using primary solvent,co-solvent (Lewis acid-base adduct approach)and solvent additives.In this review,the dynamics of numerously reported solvents on the morphological characteristics of PSCs active layer are discussed in detail.The intention is to get a clear understanding of solvent engineering induced modifications on active layer morphology in PSC devices via different crystallization routes.At last,an attempt is made to draw a framework based on different solvent coordination properties to make it easy for screening the potent solvent contender for desired PSCs precursor for a better and feasible device.
基金supported by the National Basic Research Program of China(973 Program)the National Natural Science Foundation of China.
文摘The inherent evolvability of promiscuous enzymes endows them with great potential to be artificially evolved for novel functions.Previously,we succeeded in transforming a promiscuous acylaminoacyl peptidase(apAAP)from the hyperthermophilic archaeon Aeropyrum pernix K1 into a specific carboxylesterase by making a single mutation.In order to fulfill the urgent requirement of thermostable lipolytic enzymes,in this paper we describe how the substrate preference of apAAP can be further changed from p-nitrophenyl caprylate(pNP-C8)to p-nitrophenyl laurate(pNP-C12)by protein and solvent engineering.After one round of directed evolution and subsequent saturation mutagenesis at selected residues in the active site,three variants with enhanced activity towards pNP-C12 were identified.Additionally,a combined mutant W474V/F488G/R526V/T560W was generated,which had the highest catalytic efficiency(kcat/Km)for pNP-C12,about 71-fold higher than the wild type.Its activity was further increased by solvent engineering,resulting in an activity enhancement of 280-fold compared with the wild type in the presence of 30%DMSO.The structural basis for the improved activity was studied by substrate docking and molecular dynamics simulation.It was revealed that W474V and F488G mutations caused a significant change in the geometry of the active center,which may facilitate binding and subsequent hydrolysis of bulky substrates.In conclusion,the combination of protein and solvent engineering may be an effective approach to improve the activities of promiscuous enzymes and could be used to create naturally rare hyperthermophilic enzymes.
基金supported by the National Key Research and Development Program of China(2022YFA1204800)National Natural Science Foundation of China(U21A2078,22179042,and 12104170)+1 种基金the Natural Science Foundation of Fujian Province(2023J06034)Scientific Research Funds and Subsidized Project for Postgraduate's Innovative Fund in Scientific Research of Huaqiao University。
文摘Due to their unique photoelectric properties,nontoxic tin-based perovskites are emerging candidates for efficient near-infrared LEDs.However,the facile oxidation of Sn2+and the rapid crystallization rate of tin-based perovskites result in suboptimal film quality,leading to inferior efficiencies of tin-based perovskite light-emitting diodes(Pero-LEDs).In this study,we investigate the influence of commonly used solvents on the quality of the CsSnI3 films.Remarkably,DMSO exhibits a stronger interaction with SnI2,forming a stable intermediate phase of SnI2·3DMSO.This intermediate effectively inhibits the oxidation of Sn2+and slows down the crystallization rate,bringing in lower defect state density and higher photoluminescence quantum yield of the pre-pared perovskite films.Consequently,the corresponding Pero-LEDs achieve a maximum external quantum efficiency(EQE)of 5.6%,among the most effi-cient near-infrared Pero-LEDs.In addition,the device processes ultra-low effi-ciency roll-off and high reproducibility.Our research underscores the crucial role of solvent-perovskite coordination in determining film quality.These find-ings offer valuable guidance for screening solvents to prepare highly efficient and stable tin-based perovskites.
基金supported by the National Natural Science Foundation of China(51873204,51933010,51773046)the 111 Project(B21005)+3 种基金the National 1000-Talent-Plan Program(1110010341)the Science and Technology Program of Shaanxi Province(2021KJXX-13)the Fundamental Research Funds for the Central Universities(GK202103104)the GIWAXS measurement at beamline 7.3.3 at the Advanced Light Source,LBNL,which is supposed by the Director,Office of Science,Office of Basic Energy Sciences,of the US Department of Energy(DE-AC02-05CH11231)。
文摘The use of non-halogenated solvents for the green manufacture of high-efficiency organic solar cells(OSCs)is important for their future application.However,the power conversion efficiency(PCE)of the non-halogenated solvent processed OSCs is generally lower than their halogenated counterpart due to the poor film microstructure caused by the solubility issue.Herein,we propose a halogen-free solvent system to optimize film microstructure of the photovoltaic blend based on the polymer donor D18and small-molecule acceptor(SMA)L8-BO towards high-efficiency OSCs.The solvent system is consisted of a main solvent carbon disulfide and an additive paraxylene,where the former ensures the good solution-processability and promotes the solution aggregation of L8-BO,and the latter can finely control the phase-separation process by selectively dissolving the SMA.This solvent combination robustly produces a high-quality active layer,i.e.,the bicontinuous networks of donor and acceptor with nano-sized phase-separation and strongπ-πstacking.With the effective charge generation,transport and collection,the resulting device from the non-halogenated solvent system shows a high PCE of 17.50%,which is comparable to that of the device prepared from the halogenated solvent chloroform(ca.17.11%).This article proposes a new strategy for the green fabrication of high-efficiency OSCs to accelerate their industrialization.
基金support from the National Natural Science Foundation of China(grant nos.52103237,22105178,and 62104216)the National Key R&D Program of China(grant no.2018YFA0208501)+4 种基金the Beijing National Laboratory for Molecular Sciences(grant nos.BNLMS-CXXM-202005 and 2019BMS20003)the Key R&D and Promotion Project of Henan Province(grant no.192102210032)the Opening Project of the State Key Laboratory of Advanced Technology for Float Glass(grant no.2022KF04)the Joint Research Project of Puyang Sengtong Juyuan New Materials Co.,Ltd.the Outstanding Young Talent Research Fund of Zhengzhou University.
文摘Owing to its superior efficiency and low cost,the solution-processable perovskite has rapidly become the latest favorite material in the field of photovoltaics.Although solution processing significantly reduces the threshold and cost of perovskite solar cells,the intricate composition and nonequilibrium nucleation of the perovskite precursor can result in leaky film.The precise control of perovskite nucleation and orientation is a fundamental prerequisite for achieving high-quality perovskite photoactive layers.In this process,the intermediate species that widely exists either in the precursor or the asprepared film acts as a transitional state for perovskite nucleation and growth from solution to solid,presenting an opportunity for controlling perovskite crystallization.Herein,we present an overview of the advancements in intermediates for solution-processing perovskite films to gain insights into the growth and manipulation of polycrystalline perovskite films.
基金HS acknowledges the financial support from the National Natural Science Foundation of China(Grant No.62374065)the Interdisciplinary Research promotion of HUST(No.2023JCYJ040)+4 种基金the Innovation Project of Optics Valley Laboratory(No.OVL2021BG008)the Program of Science Technology of Wenzhou City(No.G20210011)HH acknowledges the fnancial support from the Innovation and Technology Commission(No.MHP/104/21)the Shenzhen Science Technology and Innovation Commission(No.JCYJ20210324125612035)the City University of Hong Kong(Nos.9360140,7005720,9667229,9680331,7005580,and 9678291)。
文摘Infrared solar cells are more efective than normal bandgap solar cells at reducing the spectral loss in the near-infrared region,thus also at broadening the absorption spectra and improving power conversion efciency.PbS colloidal quantum dots(QDs)with tunable bandgap are ideal infrared photovoltaic materials.However,QD solar cell production sufers from small-areabased spin-coating fabrication methods and unstable QD ink.Herein,the QD ink stability mechanism was fully investigated according to Lewis acid–base theory and colloid stability theory.We further studied a mixed solvent system using dimethylformamide and butylamine,compatible with the scalable manufacture of method-blade coating.Based on the ink system,100 cm2 of uniform and dense near-infrared PbS QDs(~0.96 eV)flm was successfully prepared by blade coating.The average efciencies of above absorber-based devices reached 11.14%under AM1.5G illumination,and the 800 nm-fltered efciency achieved 4.28%.Both were the top values among blade coating method based devices.The newly developed ink showed excellent stability,and the device performance based on the ink stored for 7 h was similar to that of fresh ink.The matched solvent system for stable PbS QD ink represents a crucial step toward large area blade coating photoelectric devices.
基金supported by the National Key Research and Development Program of China(2018YFA0209303)the National Natural Science Foundation of China(U1663228,51902153,and 51972165)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘Inorganic lead halide perovskite CsPbBr3 offers attractive photophysical properties and phase stability for high-performance optoelectronic devices.However,CsPbBr3 films produced by the classic solution-based two-step method are always accompanied with impurity phases of CsPb2Br5 and Cs4PbBr6,which represents a major efficiency-limiting factor for future advances of CsPbBr3-based devices.The challenge lies in the complexity of the Cs-Pb-Br phase system,requiring both spatially and temporally precise control of the precursor stoichiometry during solution-phase growth of CsPbBr3 films.By adopting 2-methoxyethanol as the solution conversion medium instead of commonly applied methanol,the reaction between CsBr and PbBr2 can be finely controlled to yield single phase CsPbBr3 films within a few minutes;extending the solution-conversion step to 24 h does not alter the phase purity of resulting CsPbBr3 films.The present work paves the way to regulate the crystal growth behaviors of two-step solution-processed CsPbBr3 films by simple solvent engineering.
基金Financial support from the CRC for Polymers,established under the Cooperative Research Centres ProgrammeAustralian Research Council Discovery Projects (ARC DPs)+1 种基金Future Fellowship (FT) programs are acknowledgedthe support from International Postgraduate Research Scholarship (IPRS)
文摘An efficient panchromatic planar perovskite solar cell is developed based on highly uniform,lead-reduced CH3NH3Sn0.5Pb0.5I3 perovskite films with full film-coverage on the substrates.We demonstrate here that full-coverage of the CH3NH3Sn0.5Pb0.5I3 films can be developed by a facile chlorobenzene-assisted spin-coating method.A power conversion efficiency of 7 % is achieved using low-temperature processes,which is among the best-reported performance for panchromatic planar perovskite solar cells with a light-absorption over 1,000 nm.