Adding additives into peroskite precursor solution has been proven as a simple and efficient strategy to improve the quality of peroskite films.In this work,we demonstrate an effective additive strategy to improve the...Adding additives into peroskite precursor solution has been proven as a simple and efficient strategy to improve the quality of peroskite films.In this work,we demonstrate an effective additive strategy to improve the quality of all-inorganic perovskite films by adding a novel silazane additive heptamethyldisilazane(HDMS).The power conversion efficiency(PCE)of the optimized devices is enhanced from 14.55%to 15.31%with an open-circuit voltage over 1.26 V due to the higher quality perovskite films with lower trap density after the incorporation of HDMS.More interestingly,the HDMS devices exhibit superior humidity and thermal stability compared with the control ones.This work provides a simple and efficient strategy to enhance the device performance and stability of all-inorganic perovskite solar cells,which could facilitate its commercialization.展开更多
Due to the characteristics of lower material waste,higher crystallinity,roll-to-roll compatibility,and high-throughput continuous processing,blade-coating has been widely applied in the preparation of large-area organ...Due to the characteristics of lower material waste,higher crystallinity,roll-to-roll compatibility,and high-throughput continuous processing,blade-coating has been widely applied in the preparation of large-area organic solar cells.In this paper,the technique of blade-coating is introduced,including the effects of blading speed,substrate temperature,and other technological innovations during the process of blade-coating.Besides,the recent progress of blade-coating in organic solar cells is summarized and the active layer prepared by a blade-coating method is introduced in detail,including materials,processing methods,solvents,and additives.The interface layer and electrodes prepared by the blade-coating method are also discussed.Finally,some perspectives on the blade-coating method are proposed.In the foreseeable future,blade-coating will become the core of batch production of large-area organic solar cells,so as to make organic solar cells more competitive.展开更多
Organic photovoltaic semiconductors have made significant progress and have promising application prospects after decades of development.When compared with traditional semiconductors,the solution method for preparing ...Organic photovoltaic semiconductors have made significant progress and have promising application prospects after decades of development.When compared with traditional semiconductors,the solution method for preparing photovoltaic semiconductors shows the advantages of low cost and convenient preparation.However,because of the extremely poor solubility of the polymers used to prepare semiconductors,toxic solvents must be used when using the solution method,which has significant negative effects on the environment and operators and severely limits its development prospects.Organic nanoparticles(NPs),on the other hand,can avoid these issues.Because NPs are typically water or alcohol-based,no toxic solvents are used.Furthermore,NPs have been used in organic solar cells,hydrogen catalysis,organic light-emitting diodes,and other fields after nearly two decades of development,and their preparation methods have been developed.We describe the preparation,optimization,and application of NPs in photovoltaic semiconductors in this review.展开更多
PbI2/MoS2,as a typical van der Waals(vdW)heterostructure,has attracted intensive attention owing to its remarkable electronic and optoelectronic properties.In this work,the effect of defects on the electronic structur...PbI2/MoS2,as a typical van der Waals(vdW)heterostructure,has attracted intensive attention owing to its remarkable electronic and optoelectronic properties.In this work,the effect of defects on the electronic structures of a PbI2/MoS2 heterointerface has been systematically investigated.The manner in which the defects modulate the band structure of PbI2/MoS2,including the band gap,band edge,band alignment,and defect energy-level density within the band gap is discussed herein.It is shown that sulfur defects tune the band gaps,iodine defects shift the positions of the band edge and Fermi level,and lead defects realize the conversions between the straddling-gap band alignment and valence-band-aligned gap,thus enhancing the light-absorption ability of the material.展开更多
By intelligently utilizing the odd-even effect existing in the melting points of alkanes as presented in the basic textbook of Organic Chemistry, different alkoxy groups were introduced to modify the structure of comm...By intelligently utilizing the odd-even effect existing in the melting points of alkanes as presented in the basic textbook of Organic Chemistry, different alkoxy groups were introduced to modify the structure of commercial Spiro-OMeTAD to give new Spiro derivatives of Spiro-OEtTAD, Spiro-OPrTAD, Spiro-OiPrTAD and Spiro-OBuTAD, with the aim to adjust the molecular packing status in perovskite solar cells as hole transporting compounds. Excitedly, with the introduction of ethoxy groups instead of the methoxy ones in Spiro-OMeTAD, Spiro-OEtTAD-based perovskite solar cells demonstrated the highest device performance of 20.16%, higher than that of Spiro-OMeTAD(18.64%).展开更多
Here we investigate processing additive-dependent photovoltaic performance and charge recombination in organic bulk heterojunction(BHJ) solar cells based on a polymeric donor of PBDB-T blended with a non-fullerene acc...Here we investigate processing additive-dependent photovoltaic performance and charge recombination in organic bulk heterojunction(BHJ) solar cells based on a polymeric donor of PBDB-T blended with a non-fullerene acceptor m-ITIC. We find that PBDB-T:m-ITIC solar cells exhibit good compatibilities with the utilized additives(DIO, CN, DPE, and NMP) in optimal conditions, can have a high charge dissociation probability approaching 100%(with DIO), leading to ultimate efficiency >11%. Regardless of additives, we observe a dominant 1 st order monomolecular recombination with insignificant bi-molecular recombination or space-charge effects in these solar cells. Despite of impressive power conversion efficiency(PCE), it is of surprise that Shockley-Read-Hall recombination is identified to play a role in device operation. Thus, it points to the necessity to mitigate the influences of traps to further boost the efficiency in non-fullerene based organic solar cells.展开更多
Dielectric constant(ε)is an important parameter affecting the power conversion efficiency of organic solar cells(OSC).Increasingεof bulk heterojunctions in general can benefit the performance of OSCs,as an increased...Dielectric constant(ε)is an important parameter affecting the power conversion efficiency of organic solar cells(OSC).Increasingεof bulk heterojunctions in general can benefit the performance of OSCs,as an increasedεwill reduce the influence of Coulomb interaction between weakly bound electron-hole pairs on charge-transfer states or bimolecular recombination involving mobile carriers to reduce geminate and nongeminate losses.In this review,we overview the current understandings on dielectric constant and its impacts on exciton dissociation and voltage losses in OSCs and summarize recent efforts attempting to modify the dielectric properties of OSC materials through synthetic approaches.We further discuss the commonly adopted techniques for determining the parameter ofεwith stressing the testing conditions that may affect the accuracy of results.At last,we suggest that novel experimental methods to improve the dielectric constant and resultant physical processes in OSCs will be appreciated,which helps enrich the existing strategy reservoir toward enhancement of photovoltaic efficiencies.展开更多
In comparison to widely adopted bulk heterojunction(BHJ)structures for organic solar cells(OSC),exploiting the sequential deposition to form planar heterojunction(PHJ)structures enables to realize the favorable vertic...In comparison to widely adopted bulk heterojunction(BHJ)structures for organic solar cells(OSC),exploiting the sequential deposition to form planar heterojunction(PHJ)structures enables to realize the favorable vertical phase separation to facilitate charge extraction and reduce charge recombination in OSCs.However,effective tunings on the power conversion efficiency(PCE)in PHJ-OSCs are still restrained by the currently available methods.Based on a polymeric donor PBDBT-2 F(PBDBT=Poly[[4,8-bis[5-(2-ethylhexyl)-4-fluoro-2-thienyl]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl]-2,5-thiophenediyl[5,7-bis(2-ethylhexyl)-4,8-dioxo-4 H,8 H-benzo[1,2-c:4,5-c′]dithiophene-1,3-diyl]-2,5-thiophenediyl])and a non-fullerene(NF)acceptor Y6,we proposed a strategy to improve the properties of photovoltaic performances in PHJ-based OSCs through dilute dispersions of the PBDBT-2 F donor into the acceptor-dominant phase with the sequential film deposition.With the control of donor dispersions,the charge transport balance in the PHJ-OSCs is improved,leading to the expedited photocarrier sweep-out with reduced bimolecular charge recombination.As a result,a PCE of 15.4%is achieved in the PHJ-OSCs.Importantly,the PHJ solar cells with donor dispersions exhibit better thermal stability than corresponding BHJ devices,which is related to the better film morphology robustness and less affected charge sweep-out during the thermal aging.展开更多
Recently,the power conversion efficiency(PCE)of single-junction non-fullerene polymer solar cells(NF-PSCs)has surpassed 19%due to the fast development of novel donor polymers,NF-acceptors,device engineering,and interl...Recently,the power conversion efficiency(PCE)of single-junction non-fullerene polymer solar cells(NF-PSCs)has surpassed 19%due to the fast development of novel donor polymers,NF-acceptors,device engineering,and interlayer materials.The anode interlayer(AIL)plays a vital role in improving the efficiency and stability of PSCs.The challenges and opportunities in this research area encourage researchers to pursue great innovation in developing new materials and strategies for highly efficient NF-PSCs.This review summarizes the recent development of AIL materials and their modification strategies in single-junction NF-PSCs.Firstly,a brief introduction,key functions,basic requirements,and peculiar features of AILs when employed in NF-PSCs are discussed.Then,the impact of AIL materials(including organic,inorganic,and hybrid materials)on the PCE and the stability of NF-PSCs are described.Afterward,the fabrication of large-area devices and related issues are highlighted.The summary and the future challenges regarding efficient AIL are summarized in the last section of this review.展开更多
基金financially supported by the National Key Research and Development Program of China(Grant No.2017YFA0206600)the National Natural Science Foundation of China(Grant No.21922505)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB36000000)。
文摘Adding additives into peroskite precursor solution has been proven as a simple and efficient strategy to improve the quality of peroskite films.In this work,we demonstrate an effective additive strategy to improve the quality of all-inorganic perovskite films by adding a novel silazane additive heptamethyldisilazane(HDMS).The power conversion efficiency(PCE)of the optimized devices is enhanced from 14.55%to 15.31%with an open-circuit voltage over 1.26 V due to the higher quality perovskite films with lower trap density after the incorporation of HDMS.More interestingly,the HDMS devices exhibit superior humidity and thermal stability compared with the control ones.This work provides a simple and efficient strategy to enhance the device performance and stability of all-inorganic perovskite solar cells,which could facilitate its commercialization.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.21922505 and 52273245)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB36000000).
文摘Due to the characteristics of lower material waste,higher crystallinity,roll-to-roll compatibility,and high-throughput continuous processing,blade-coating has been widely applied in the preparation of large-area organic solar cells.In this paper,the technique of blade-coating is introduced,including the effects of blading speed,substrate temperature,and other technological innovations during the process of blade-coating.Besides,the recent progress of blade-coating in organic solar cells is summarized and the active layer prepared by a blade-coating method is introduced in detail,including materials,processing methods,solvents,and additives.The interface layer and electrodes prepared by the blade-coating method are also discussed.Finally,some perspectives on the blade-coating method are proposed.In the foreseeable future,blade-coating will become the core of batch production of large-area organic solar cells,so as to make organic solar cells more competitive.
基金supported by the National Natural Science Foundation of China(Nos.21922505 and 52273245)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB36000000).
文摘Organic photovoltaic semiconductors have made significant progress and have promising application prospects after decades of development.When compared with traditional semiconductors,the solution method for preparing photovoltaic semiconductors shows the advantages of low cost and convenient preparation.However,because of the extremely poor solubility of the polymers used to prepare semiconductors,toxic solvents must be used when using the solution method,which has significant negative effects on the environment and operators and severely limits its development prospects.Organic nanoparticles(NPs),on the other hand,can avoid these issues.Because NPs are typically water or alcohol-based,no toxic solvents are used.Furthermore,NPs have been used in organic solar cells,hydrogen catalysis,organic light-emitting diodes,and other fields after nearly two decades of development,and their preparation methods have been developed.We describe the preparation,optimization,and application of NPs in photovoltaic semiconductors in this review.
基金National Natural Science Foundation of China(Grant No.11672079)the National Science Foundation of Beijing(Grant No.2184130)。
文摘PbI2/MoS2,as a typical van der Waals(vdW)heterostructure,has attracted intensive attention owing to its remarkable electronic and optoelectronic properties.In this work,the effect of defects on the electronic structures of a PbI2/MoS2 heterointerface has been systematically investigated.The manner in which the defects modulate the band structure of PbI2/MoS2,including the band gap,band edge,band alignment,and defect energy-level density within the band gap is discussed herein.It is shown that sulfur defects tune the band gaps,iodine defects shift the positions of the band edge and Fermi level,and lead defects realize the conversions between the straddling-gap band alignment and valence-band-aligned gap,thus enhancing the light-absorption ability of the material.
基金supported by the National Natural Science Foundation of China (21734007, 51573140, 51673151, 21773045)the Natural Science Foundation of Hubei Province (2017CFA002)the Fundamental Research Funds for the Central Universities (2042017kf0247, 2042018kf0014)
文摘By intelligently utilizing the odd-even effect existing in the melting points of alkanes as presented in the basic textbook of Organic Chemistry, different alkoxy groups were introduced to modify the structure of commercial Spiro-OMeTAD to give new Spiro derivatives of Spiro-OEtTAD, Spiro-OPrTAD, Spiro-OiPrTAD and Spiro-OBuTAD, with the aim to adjust the molecular packing status in perovskite solar cells as hole transporting compounds. Excitedly, with the introduction of ethoxy groups instead of the methoxy ones in Spiro-OMeTAD, Spiro-OEtTAD-based perovskite solar cells demonstrated the highest device performance of 20.16%, higher than that of Spiro-OMeTAD(18.64%).
基金the National Natural Science Foundation of China (No. 21471022)the National Natural Science Foundation of China (No. 21674006)+1 种基金the Chinese Academy of Science (100 Top Young Scientists Program, No. QYZDB-SSW-SLH033)the National Key Research and Development Program of China (No. 2017YFA0206600)
文摘Here we investigate processing additive-dependent photovoltaic performance and charge recombination in organic bulk heterojunction(BHJ) solar cells based on a polymeric donor of PBDB-T blended with a non-fullerene acceptor m-ITIC. We find that PBDB-T:m-ITIC solar cells exhibit good compatibilities with the utilized additives(DIO, CN, DPE, and NMP) in optimal conditions, can have a high charge dissociation probability approaching 100%(with DIO), leading to ultimate efficiency >11%. Regardless of additives, we observe a dominant 1 st order monomolecular recombination with insignificant bi-molecular recombination or space-charge effects in these solar cells. Despite of impressive power conversion efficiency(PCE), it is of surprise that Shockley-Read-Hall recombination is identified to play a role in device operation. Thus, it points to the necessity to mitigate the influences of traps to further boost the efficiency in non-fullerene based organic solar cells.
基金This work was supported by the National Natural Science Foundation of China(Nos.21875012,21674006).
文摘Dielectric constant(ε)is an important parameter affecting the power conversion efficiency of organic solar cells(OSC).Increasingεof bulk heterojunctions in general can benefit the performance of OSCs,as an increasedεwill reduce the influence of Coulomb interaction between weakly bound electron-hole pairs on charge-transfer states or bimolecular recombination involving mobile carriers to reduce geminate and nongeminate losses.In this review,we overview the current understandings on dielectric constant and its impacts on exciton dissociation and voltage losses in OSCs and summarize recent efforts attempting to modify the dielectric properties of OSC materials through synthetic approaches.We further discuss the commonly adopted techniques for determining the parameter ofεwith stressing the testing conditions that may affect the accuracy of results.At last,we suggest that novel experimental methods to improve the dielectric constant and resultant physical processes in OSCs will be appreciated,which helps enrich the existing strategy reservoir toward enhancement of photovoltaic efficiencies.
基金the National Natural Science Foundation of China(21875012,21674006,21773045)the National Key Research and Development Program of China(2017YFA0206600)+1 种基金the Chinese Academy of Science(100 Top Young Scientists Program)the program of“Academic Excellence Foundation of BUAA for Ph D Students”。
文摘In comparison to widely adopted bulk heterojunction(BHJ)structures for organic solar cells(OSC),exploiting the sequential deposition to form planar heterojunction(PHJ)structures enables to realize the favorable vertical phase separation to facilitate charge extraction and reduce charge recombination in OSCs.However,effective tunings on the power conversion efficiency(PCE)in PHJ-OSCs are still restrained by the currently available methods.Based on a polymeric donor PBDBT-2 F(PBDBT=Poly[[4,8-bis[5-(2-ethylhexyl)-4-fluoro-2-thienyl]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl]-2,5-thiophenediyl[5,7-bis(2-ethylhexyl)-4,8-dioxo-4 H,8 H-benzo[1,2-c:4,5-c′]dithiophene-1,3-diyl]-2,5-thiophenediyl])and a non-fullerene(NF)acceptor Y6,we proposed a strategy to improve the properties of photovoltaic performances in PHJ-based OSCs through dilute dispersions of the PBDBT-2 F donor into the acceptor-dominant phase with the sequential film deposition.With the control of donor dispersions,the charge transport balance in the PHJ-OSCs is improved,leading to the expedited photocarrier sweep-out with reduced bimolecular charge recombination.As a result,a PCE of 15.4%is achieved in the PHJ-OSCs.Importantly,the PHJ solar cells with donor dispersions exhibit better thermal stability than corresponding BHJ devices,which is related to the better film morphology robustness and less affected charge sweep-out during the thermal aging.
基金Key Project of Department of Education of Guangdong Province,Grant/Award Number:2018KZDXM059National Key Research and Development Program of China,Grant/Award Number:2017YFA0206600+2 种基金National Natural Science Foundation of China,Grant/Award Numbers:21922505,62074102Science and Technology Plan Project of Shenzhen,Grant/Award Number:JCYJ20190808153409238Strategic Priority Research Program of Chinese Academy of Sciences,Grant/Award Number:XDB36000000。
文摘Recently,the power conversion efficiency(PCE)of single-junction non-fullerene polymer solar cells(NF-PSCs)has surpassed 19%due to the fast development of novel donor polymers,NF-acceptors,device engineering,and interlayer materials.The anode interlayer(AIL)plays a vital role in improving the efficiency and stability of PSCs.The challenges and opportunities in this research area encourage researchers to pursue great innovation in developing new materials and strategies for highly efficient NF-PSCs.This review summarizes the recent development of AIL materials and their modification strategies in single-junction NF-PSCs.Firstly,a brief introduction,key functions,basic requirements,and peculiar features of AILs when employed in NF-PSCs are discussed.Then,the impact of AIL materials(including organic,inorganic,and hybrid materials)on the PCE and the stability of NF-PSCs are described.Afterward,the fabrication of large-area devices and related issues are highlighted.The summary and the future challenges regarding efficient AIL are summarized in the last section of this review.
