In perovskite solar cells(PSCs),the inherent defects of perovskite film and the random distribution of excess lead iodide(PbI_(2))prevent the improvement of efficiency and stability.Herein,natural cellulose is used as...In perovskite solar cells(PSCs),the inherent defects of perovskite film and the random distribution of excess lead iodide(PbI_(2))prevent the improvement of efficiency and stability.Herein,natural cellulose is used as the raw material to design a series of cellulose derivatives for perovskite crystallization engineering.The cationic cellulose derivative C-Im-CN with cyano-imidazolium(Im-CN)cation and chloride anion prominently promotes the crystallization process,grain growth,and directional orientation of perovskite.Meanwhile,excess PbI_(2)is transferred to the surface of perovskite grains or formed plate-like crystallites in local domains.These effects result in suppressing defect formation,decreasing grain boundaries,enhancing carrier extraction,inhibiting non-radiative recombination,and dramatically prolonging carrier lifetimes.Thus,the PSCs exhibit a high power conversion efficiency of 24.71%.Moreover,C-Im-CN has multiple interaction sites and polymer skeleton,so the unencapsulated PSCs maintain above 91.3%of their initial efficiencies after 3000 h of continuous operation in a conventional air atmosphere and have good stability under high humidity conditions.The utilization of biopolymers with excellent structure-designability to manage the perovskite opens a state-of-the-art avenue for manufacturing and improving PSCs.展开更多
Lead halide perovskite solar cells(PSCs) have become a promising next-generation photovoltaic technology due to their skyrocketed power conversion efficiency. However, the device stability issues may restrict their co...Lead halide perovskite solar cells(PSCs) have become a promising next-generation photovoltaic technology due to their skyrocketed power conversion efficiency. However, the device stability issues may restrict their commercial applications, which are dominated by various chemical reactions of perovskite layers. Hence, a comprehensive illustration on the stability of perovskite films in PSCs is urgently needed. In this review article, chemical reactions of perovskite films under different environmental conditions(e.g., moisture,oxygen, light) and with charge transfer materials and metal electrodes are systematically elucidated. Effective strategies for suppressing the degradation reactions of perovskites, such as buffer layer introduction and additives engineering,are specified. Finally, conclusions and outlooks for this field are proposed. The comprehensive review will provide a guideline on the material engineering and device design for PSCs.展开更多
Perovskite solar cells(PSCs)are regarded as promising candidates for future renewable energy production.High-density defects in the perovskite films,however,lead to unsatisfactory device performances.Here,poly(propyle...Perovskite solar cells(PSCs)are regarded as promising candidates for future renewable energy production.High-density defects in the perovskite films,however,lead to unsatisfactory device performances.Here,poly(propylene glycol)bis(2-aminopropyl ether)(PEA)additive is utilized to passivate the trap states in perovskite.The PEA molecules chemically interact with lead ions in perovskite,considerably passivate surface and bulk defects,which is in favor of charge transfer and extraction.Furthermore,the PEA additive can efficiently block moisture and oxygen to prolong the device lifetime.As a result,PEA-treated MAPbI3(MA:CH3NH3)solar cells show increased power conversion efficiency(PCE)(from 17.18 to 18.87%)and good longterm stability.When PEA is introduced to(FAPbI3)1-x(MAPbBr3)x(FA:HC(NH2)2)solar cells,the PCE is enhanced from 19.66 to 21.60%.For both perovskites,their severe device hysteresis is efficiently relieved by PEA.展开更多
Development of lead-free halide perovskites that are innocuous and stable has become an attractive trend in resistive random access memory(RRAM)fields.However,their inferior memory properties compared with the lead-ba...Development of lead-free halide perovskites that are innocuous and stable has become an attractive trend in resistive random access memory(RRAM)fields.However,their inferior memory properties compared with the lead-based analogs hinder their commercialization.Herein,the lead-free Cs_(3)Bi_(2)Br_(9)perovskite quantum dot(PQD)-based RRAMs are reported with outstanding memory performance,where Cs_(3)Bi_(2)Br_(9)quantum dots(QDs)are synthesized via a modified ligand-assisted recrystallization process.This is the first report of applying Cs_(3)Bi_(2)Br_(9)QDs as the switching layer for RRAM device.The Cs_(3)Bi_(2)Br_(9)QD device demonstrates nonvolatile resistive switching(RS)effect with large ON/OFF ratio of 105,low set voltage of-0.45 V,as well as good reliability,reproducibility,and flexibility.Concurrently,the device exhibits the notable tolerance toward moisture,heat and light illumination,and long-term stability of 200 days.More impressively,the device shows the reliable light-modulated RS behavior,and therefrom the logic gate operations including"AND"and"OR"are implemented,foreboding its prospect in logic circuits integrated with storage and computation.Such multifunctionality of device could be derived from the unique 2D layered crystal structure,small particle size,quantum confinement effect,and photoresponse of Cs_(3)Bi_(2)Br_(9)QDs.This work provides the strategy toward the high-performance RRAMs based on stable and eco-friendly perovskites for future applications.展开更多
Hypertrophic cardiomyopathy(HCM)is the most common inherited heart disease and is characterized by primary left ventricular hypertrophy usually caused by mutations in sarcomere genes.The mechanism underlying cardiac r...Hypertrophic cardiomyopathy(HCM)is the most common inherited heart disease and is characterized by primary left ventricular hypertrophy usually caused by mutations in sarcomere genes.The mechanism underlying cardiac remodeling in HCM remains incompletely understood.An investigation of HCM through integrative analysis at multi-omics levels will be helpful for treating HCM.DNA methylation and chromatin accessibility,as well as gene expression,were assessed by nucleosome occupancy and methylome sequencing(NOMe-seq)and RNA-seq,respectively,using the cardiac tissues of HCM patients.Compared with those of the controls,the transcriptome,DNA methylome,and chromatin accessibility of the HCM myocardium showed multifaceted differences.At the transcriptome level,HCM hearts returned to the fetal gene program through decreased sarcomeric and metabolic gene expression and increased extracellular matrix gene expression.In the DNA methylome,hypermethylated and hypomethylated differentially methylated regions were identified in HCM.At the chromatin accessibility level,HCM hearts showed changes in different genome elements.Several transcription factors,including SP1 and EGR1,exhibited a fetal-like pattern of binding motifs in nucleosome-depleted regions in HCM.In particular,the inhibition of SP1 or EGR1 in an HCM mouse model harboring sarcomere mutations markedly alleviated the HCM phenotype of the mutant mice and reversed fetal gene reprogramming.Overall,this study not only provides a high-precision multi-omics map of HCM heart tissue but also sheds light on the therapeutic strategy by intervening in the fetal gene reprogramming in HCM.展开更多
Finding ways to produce dense and smooth perovskite films with negligible defects is vital for achieving high-efficiency perovskite solar cells(PSCs).Herein,we aim to enhance the quality of the perovskite films throug...Finding ways to produce dense and smooth perovskite films with negligible defects is vital for achieving high-efficiency perovskite solar cells(PSCs).Herein,we aim to enhance the quality of the perovskite films through the utilization of a multifunctional additive in the perovskite anti-solvent,a strategy referred to as anti-solvent additive engineering.Specifically,we introduce ortho-substituted-4′-(4,4″-di-tertbutyl-1,1′:3′,1″-terphenyl)-graphdiyne(o-TB-GDY)as an AAE additive,characterized by its sp/sp^2-cohybridized and highlyπ-conjugated structure,into the anti-solvent.o-TB-GDY not only significantly passivates undercoordinated lead defects(through potent coordination originating from specific highπ–electron conjugation),but also serves as nucleation seeds to effectively enhance the nucleation and growth of perovskite crystals.This markedly reduces defects and non-radiative recombination,thereby increasing the power conversion efficiency(PCE)to 25.62%(certified as 25.01%).Meanwhile,the PSCs exhibit largely enhanced stability,maintaining 92.6%of their initial PCEs after 500 h continuous 1-sun illumination at~23°C in a nitrogen-filled glove box.展开更多
Organic solar cells(OSCs)have drawn substantial attention in recent two decades due to their features of solution processability,low cost,and light weight[1].The active layer of OSCs is usually composed of an electron...Organic solar cells(OSCs)have drawn substantial attention in recent two decades due to their features of solution processability,low cost,and light weight[1].The active layer of OSCs is usually composed of an electron donor(D)and an electron acceptor(A).The D/A system can form interpenetrated nanoscale network,which allows efficient exciton dissociation and hence charge carrier generation.However,the efficiency of such binary OSCs is gen-展开更多
An ideal organic thin film photodetectors(OTFPs) should adopt a hierarchical, multilayer p-type/blend-type/n-type(PIN) structure,with each layer having a specific purpose which could greatly improve the exciton dissoc...An ideal organic thin film photodetectors(OTFPs) should adopt a hierarchical, multilayer p-type/blend-type/n-type(PIN) structure,with each layer having a specific purpose which could greatly improve the exciton dissociation while guarantee efficient charge transport. However, for the traditional layer-by-layer solution fabrication procedure, the solvent used can induce organic material mixing and molecular disordering between each layer. Hence, such architecture for OTFPs can now only be formed via thermal evaporation. In this paper, a contact-film-transfer method is demonstrated to all-solution processing organic PIN OTFPs on flexible substrates. The fabricated PIN OTFPs exhibit high photoresponse and high stability under continuous mechanical bending. Hence,the method we described here should represent an important step in the development of OTFPs in the future.展开更多
基金supported by the National Natural Science Foundation of China(No.52173292 and U2004211)the Youth Innovation Promotion Association CAS(No.2018040).
文摘In perovskite solar cells(PSCs),the inherent defects of perovskite film and the random distribution of excess lead iodide(PbI_(2))prevent the improvement of efficiency and stability.Herein,natural cellulose is used as the raw material to design a series of cellulose derivatives for perovskite crystallization engineering.The cationic cellulose derivative C-Im-CN with cyano-imidazolium(Im-CN)cation and chloride anion prominently promotes the crystallization process,grain growth,and directional orientation of perovskite.Meanwhile,excess PbI_(2)is transferred to the surface of perovskite grains or formed plate-like crystallites in local domains.These effects result in suppressing defect formation,decreasing grain boundaries,enhancing carrier extraction,inhibiting non-radiative recombination,and dramatically prolonging carrier lifetimes.Thus,the PSCs exhibit a high power conversion efficiency of 24.71%.Moreover,C-Im-CN has multiple interaction sites and polymer skeleton,so the unencapsulated PSCs maintain above 91.3%of their initial efficiencies after 3000 h of continuous operation in a conventional air atmosphere and have good stability under high humidity conditions.The utilization of biopolymers with excellent structure-designability to manage the perovskite opens a state-of-the-art avenue for manufacturing and improving PSCs.
基金financially supported by the Research Grants Council (RGC) of Hong Kong, China (Project No. 15306822)Innovation and Technology Commission of Hong Kong, China (Innovation and Technology Fund-Guangdong-Hong Kong Technology Cooperation Funding Scheme (ITF-TCFS), Project No. GHP/042/19SZ)+2 种基金financially supported by the Research Institute of Intelligent Wearable Systems of the Hong Kong Polytechnic University, Hong Kong, China (Project Code: CD46)supported by the funding for Projects of Strategic Importance of the Hong Kong Polytechnic University (Project Code: 1-ZE2X)supported by Shenzhen Science and Technology Innovation Commission, (Project No.: SGDX20210823103401011)。
文摘Lead halide perovskite solar cells(PSCs) have become a promising next-generation photovoltaic technology due to their skyrocketed power conversion efficiency. However, the device stability issues may restrict their commercial applications, which are dominated by various chemical reactions of perovskite layers. Hence, a comprehensive illustration on the stability of perovskite films in PSCs is urgently needed. In this review article, chemical reactions of perovskite films under different environmental conditions(e.g., moisture,oxygen, light) and with charge transfer materials and metal electrodes are systematically elucidated. Effective strategies for suppressing the degradation reactions of perovskites, such as buffer layer introduction and additives engineering,are specified. Finally, conclusions and outlooks for this field are proposed. The comprehensive review will provide a guideline on the material engineering and device design for PSCs.
基金Financial support for this research is provided by the National Key Research Program of China(2016YFA0200104)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB12030200).
文摘Perovskite solar cells(PSCs)are regarded as promising candidates for future renewable energy production.High-density defects in the perovskite films,however,lead to unsatisfactory device performances.Here,poly(propylene glycol)bis(2-aminopropyl ether)(PEA)additive is utilized to passivate the trap states in perovskite.The PEA molecules chemically interact with lead ions in perovskite,considerably passivate surface and bulk defects,which is in favor of charge transfer and extraction.Furthermore,the PEA additive can efficiently block moisture and oxygen to prolong the device lifetime.As a result,PEA-treated MAPbI3(MA:CH3NH3)solar cells show increased power conversion efficiency(PCE)(from 17.18 to 18.87%)and good longterm stability.When PEA is introduced to(FAPbI3)1-x(MAPbBr3)x(FA:HC(NH2)2)solar cells,the PCE is enhanced from 19.66 to 21.60%.For both perovskites,their severe device hysteresis is efficiently relieved by PEA.
基金supported by the National Natural Science Foundation of China(21374106)National Natural Science Foundation of China(11774318,12074347,and U1304212)National Key Research Program of China(2016YFA0200104).
文摘Development of lead-free halide perovskites that are innocuous and stable has become an attractive trend in resistive random access memory(RRAM)fields.However,their inferior memory properties compared with the lead-based analogs hinder their commercialization.Herein,the lead-free Cs_(3)Bi_(2)Br_(9)perovskite quantum dot(PQD)-based RRAMs are reported with outstanding memory performance,where Cs_(3)Bi_(2)Br_(9)quantum dots(QDs)are synthesized via a modified ligand-assisted recrystallization process.This is the first report of applying Cs_(3)Bi_(2)Br_(9)QDs as the switching layer for RRAM device.The Cs_(3)Bi_(2)Br_(9)QD device demonstrates nonvolatile resistive switching(RS)effect with large ON/OFF ratio of 105,low set voltage of-0.45 V,as well as good reliability,reproducibility,and flexibility.Concurrently,the device exhibits the notable tolerance toward moisture,heat and light illumination,and long-term stability of 200 days.More impressively,the device shows the reliable light-modulated RS behavior,and therefrom the logic gate operations including"AND"and"OR"are implemented,foreboding its prospect in logic circuits integrated with storage and computation.Such multifunctionality of device could be derived from the unique 2D layered crystal structure,small particle size,quantum confinement effect,and photoresponse of Cs_(3)Bi_(2)Br_(9)QDs.This work provides the strategy toward the high-performance RRAMs based on stable and eco-friendly perovskites for future applications.
基金supported by the National Natural Science Foundation of China(Grant No.82170290)the CAMS Innovation Fund for Medical Sciences(Grant No.2023-I2M-1-001)+1 种基金Project funded by China Postdoctoral Science Foundation(Grant No.2023M732704)the Open Research Fund of the National Center for Protein Sciences at Peking University in Beijing.
文摘Hypertrophic cardiomyopathy(HCM)is the most common inherited heart disease and is characterized by primary left ventricular hypertrophy usually caused by mutations in sarcomere genes.The mechanism underlying cardiac remodeling in HCM remains incompletely understood.An investigation of HCM through integrative analysis at multi-omics levels will be helpful for treating HCM.DNA methylation and chromatin accessibility,as well as gene expression,were assessed by nucleosome occupancy and methylome sequencing(NOMe-seq)and RNA-seq,respectively,using the cardiac tissues of HCM patients.Compared with those of the controls,the transcriptome,DNA methylome,and chromatin accessibility of the HCM myocardium showed multifaceted differences.At the transcriptome level,HCM hearts returned to the fetal gene program through decreased sarcomeric and metabolic gene expression and increased extracellular matrix gene expression.In the DNA methylome,hypermethylated and hypomethylated differentially methylated regions were identified in HCM.At the chromatin accessibility level,HCM hearts showed changes in different genome elements.Several transcription factors,including SP1 and EGR1,exhibited a fetal-like pattern of binding motifs in nucleosome-depleted regions in HCM.In particular,the inhibition of SP1 or EGR1 in an HCM mouse model harboring sarcomere mutations markedly alleviated the HCM phenotype of the mutant mice and reversed fetal gene reprogramming.Overall,this study not only provides a high-precision multi-omics map of HCM heart tissue but also sheds light on the therapeutic strategy by intervening in the fetal gene reprogramming in HCM.
基金supported by the National Key Research Program of China(Y91Z0152B4,2018YFA0703501)the National Nature Science Foundation of China(22172173,22021002)。
文摘Finding ways to produce dense and smooth perovskite films with negligible defects is vital for achieving high-efficiency perovskite solar cells(PSCs).Herein,we aim to enhance the quality of the perovskite films through the utilization of a multifunctional additive in the perovskite anti-solvent,a strategy referred to as anti-solvent additive engineering.Specifically,we introduce ortho-substituted-4′-(4,4″-di-tertbutyl-1,1′:3′,1″-terphenyl)-graphdiyne(o-TB-GDY)as an AAE additive,characterized by its sp/sp^2-cohybridized and highlyπ-conjugated structure,into the anti-solvent.o-TB-GDY not only significantly passivates undercoordinated lead defects(through potent coordination originating from specific highπ–electron conjugation),but also serves as nucleation seeds to effectively enhance the nucleation and growth of perovskite crystals.This markedly reduces defects and non-radiative recombination,thereby increasing the power conversion efficiency(PCE)to 25.62%(certified as 25.01%).Meanwhile,the PSCs exhibit largely enhanced stability,maintaining 92.6%of their initial PCEs after 500 h continuous 1-sun illumination at~23°C in a nitrogen-filled glove box.
基金the financial support from the National Key Research and Development Program of China(2016YFA0200104),the National Key Research and Development Program of China(2017YFA0206600)for financial supportthe National Basic Research Program of China(2014CB643600 and 2014CB643503)+1 种基金the Strategic Priority Research Program(CAS)(XDB12030200)the National Natural Science Foundation of China(U1401244,51773045,21572041,21772030,51503050 and 21704021)
文摘Organic solar cells(OSCs)have drawn substantial attention in recent two decades due to their features of solution processability,low cost,and light weight[1].The active layer of OSCs is usually composed of an electron donor(D)and an electron acceptor(A).The D/A system can form interpenetrated nanoscale network,which allows efficient exciton dissociation and hence charge carrier generation.However,the efficiency of such binary OSCs is gen-
基金supported by the National Basic Research Program of China (2014CB643600, 2014CB643503)
文摘An ideal organic thin film photodetectors(OTFPs) should adopt a hierarchical, multilayer p-type/blend-type/n-type(PIN) structure,with each layer having a specific purpose which could greatly improve the exciton dissociation while guarantee efficient charge transport. However, for the traditional layer-by-layer solution fabrication procedure, the solvent used can induce organic material mixing and molecular disordering between each layer. Hence, such architecture for OTFPs can now only be formed via thermal evaporation. In this paper, a contact-film-transfer method is demonstrated to all-solution processing organic PIN OTFPs on flexible substrates. The fabricated PIN OTFPs exhibit high photoresponse and high stability under continuous mechanical bending. Hence,the method we described here should represent an important step in the development of OTFPs in the future.
