Self-assembled molecules(SAMs) have shown great potential in replacing bulk charge selective contact layers in high-performance perovskite solar cells(PSCs) due to their low material consumption and simple processing....Self-assembled molecules(SAMs) have shown great potential in replacing bulk charge selective contact layers in high-performance perovskite solar cells(PSCs) due to their low material consumption and simple processing. Herein, we design and synthesize a series of donor-acceptor(D-A) type SAMs(MPA-BTCA, MPA-BT-BA, and MPA-BT-RA, where MPA is 4-methoxy-N-(4-methoxyphenyl)-N-phenylaniline;BT is benzo[c][1,2,5]-thiadiazole;CA is 2-cyanoacrylic acid, BA is benzoic acid, RA is rhodanine-3-propionic acid) with distinct anchoring groups, which show dramatically different properties. MPA-BTCA with CA anchoring groups exhibited stronger dipole moments and formed a homogeneous monolayer on the indium tin oxide(ITO) surface by adopting an upstanding self-assembling mode. However, the MPA-BT-RA molecules tend to aggregate severely in solid state due to the sp~3 hybridization of the carbon atom on the RA group, which is not favorable for achieving a long-range ordered self-assembled layer.Consequently, benefiting from high dipole moment, as well as dense and uniform self-assembled film,the device based on MPA-BT-CA yielded a remarkable power conversion efficiency(PCE) of 21.81%.Encouragingly, an impressive PCE approaching 20% can still be obtained for the MPA-BT-CA-based PSCs as the device area is increased to 0.80 cm^(2). Our work sheds light on the design principles for developing hole selecting SAMs, which will pave a way for realizing highly efficient, flexible, and large-area PSCs.展开更多
The ternary strategy has demonstrated its efficacy in improving charge transport in organic solar cells(OSCs).Here,three novel non-fullerene acceptors,SN6C9-4F,SN6C9-4Cl and SN6C10-4F,based on S,N-heteroacene linear b...The ternary strategy has demonstrated its efficacy in improving charge transport in organic solar cells(OSCs).Here,three novel non-fullerene acceptors,SN6C9-4F,SN6C9-4Cl and SN6C10-4F,based on S,N-heteroacene linear backbone were designed and synthesized.The three acceptors exhibit excellent molecular coplanarity,high crystallinity and possess a deep-lying lowest unoccupied molecular orbital energy level,which is beneficial for charge transport and injection in organic field-effect transistors(OFETs).Notably,the OFET devices based on all three acceptors achieved impressive electron mobilities,with SN6C10-4F achieving up to 0.73 cm^(2)·V^(-1)·s^(-1),which is one of the highest values among A-D-A type small molecules.In addition,the OSCs device based on PBDB-T:SN6C9-4F exhibited the best power conversion efficiency of 12.07%owing to its optimal morphology and enhanced charge transport.Moreover,the incorporation of SN6C9-4F into the efficient PM6:L8-BO binary system to form ternary OSCs resulted in extended absorption range,enhanced donor crystallization,improved and more balanced charge transport,ultimately leading to an improvement of PCE from 17.78%to 18.32%.This study highlights the potential of developing acceptors with distinct structures from Y-series acceptors to broaden absorption and regulate donor crystallization,providing a novel approach to enhance the PCE of OSCs.展开更多
All-polymer solar cells(all-PSCs) have received extensive attention due to their excellent mechanical robustness and performance stability. However, the power conversion efficiency(PCE) of all-PSCs still lags behind t...All-polymer solar cells(all-PSCs) have received extensive attention due to their excellent mechanical robustness and performance stability. However, the power conversion efficiency(PCE) of all-PSCs still lags behind those of organic solar cells(OSCs)based on non-fullerene small molecule acceptors. Herein, we report highly efficient all-PSCs via sequential deposition(SD) with donor and acceptor layers coated sequentially to optimize the film microstructure. Compared with the bulk heterojunction(BHJ)all-PSCs, an optimized morphology with vertical component distribution was achieved for the SD-processed all-PSCs due to the synergistic effect of swelling of polymer films and using additive. Such strategy involves using chlorobenzene as the first layer processing-solvent for polymer donor, chloroform as the second processing-solvent for polymer acceptor with trace 1-chloronaphthalene, efficiently promoting exciton dissociation and charge extraction and reducing trap-assisted recombination.Consequently, over 16% all-PSCs fabricated via SD method was realized for the first time, which is much higher than that(15.2%) of its BHJ counterpart and also among the highest PCEs in all-PSCs. We have further demonstrated the generality of this approach in various all-polymer systems. This work indicates that the SD method can yield excellent all-PSCs and provides a facile approach to fabricating high-performance all-PSCs.展开更多
High-performance,cost-effective hole-transport materials(HTMs)are greatly desired for the commercialization of perovskite solar cells(PVSCs).Herein,two new HTMs,TPA-FO and TPA-PDO,are devised and synthesized,which hav...High-performance,cost-effective hole-transport materials(HTMs)are greatly desired for the commercialization of perovskite solar cells(PVSCs).Herein,two new HTMs,TPA-FO and TPA-PDO,are devised and synthesized,which have a donor-acceptor-donor(D-A-D)type molecule design featuring carbonyl group-functionalized arenes as the acceptor(A)units.The carbonyl group at the central core of HTMs can not only tune frontier molecular orbital(FMO)energy levels and surface wettability,but also can enable efficient surface passivation effects,resulting in reduced recombination loss.When employed as HTMs in inverted PVSCs without using dopant,TPA-FO with one carbonyl group yields a high power conversion efficiency(PCE)of 20.24%,which is among the highest values reported in the inverted PVSCs with dopant-free HTMs.More importantly,the facile one-step synthetic process enables a low cost of 30 USD g^(-1) for TPA-FO,much cheaper than the most studied HTMs used for high-efficiency dopant-free PVSCs.These results demonstrate the potential of D-A-D type molecules with carbonyl group-functionalized arene core in developing the low-cost dopant-free HTMs toward highly efficient PVSCs.展开更多
基金financial support from the National Natural Science Foundation of China (NSFC)(21805128)the National Natural Science Foundation of China (21774055)+3 种基金the financial support from the National Natural Science Foundation of China(21975260)the Shenzhen Science and Technology Innovation Commission(JCYJ20180504165709042)financial support of Guangdong Provincial Key Laboratory Program(2021B1212040001) from the Department of Science and Technology of Guangdong Provincethe NSFC-CNR exchange program of NSFC(22011530391)。
文摘Self-assembled molecules(SAMs) have shown great potential in replacing bulk charge selective contact layers in high-performance perovskite solar cells(PSCs) due to their low material consumption and simple processing. Herein, we design and synthesize a series of donor-acceptor(D-A) type SAMs(MPA-BTCA, MPA-BT-BA, and MPA-BT-RA, where MPA is 4-methoxy-N-(4-methoxyphenyl)-N-phenylaniline;BT is benzo[c][1,2,5]-thiadiazole;CA is 2-cyanoacrylic acid, BA is benzoic acid, RA is rhodanine-3-propionic acid) with distinct anchoring groups, which show dramatically different properties. MPA-BTCA with CA anchoring groups exhibited stronger dipole moments and formed a homogeneous monolayer on the indium tin oxide(ITO) surface by adopting an upstanding self-assembling mode. However, the MPA-BT-RA molecules tend to aggregate severely in solid state due to the sp~3 hybridization of the carbon atom on the RA group, which is not favorable for achieving a long-range ordered self-assembled layer.Consequently, benefiting from high dipole moment, as well as dense and uniform self-assembled film,the device based on MPA-BT-CA yielded a remarkable power conversion efficiency(PCE) of 21.81%.Encouragingly, an impressive PCE approaching 20% can still be obtained for the MPA-BT-CA-based PSCs as the device area is increased to 0.80 cm^(2). Our work sheds light on the design principles for developing hole selecting SAMs, which will pave a way for realizing highly efficient, flexible, and large-area PSCs.
基金financially supported by the National Natural Science Foundation of China(NSFC)(52333006,51973032,21905043,22275078 and 52173171)the Jiangxi Provincial Natural Science Foundation(20212ACB203005,20224ACB214002)+1 种基金the Thous and Talents Plan of Jiangxi Province(jxsq2019101051)financial support from Research Grants Council(RGC)of Hong Kong(General Research Fund No.14303519).
文摘The ternary strategy has demonstrated its efficacy in improving charge transport in organic solar cells(OSCs).Here,three novel non-fullerene acceptors,SN6C9-4F,SN6C9-4Cl and SN6C10-4F,based on S,N-heteroacene linear backbone were designed and synthesized.The three acceptors exhibit excellent molecular coplanarity,high crystallinity and possess a deep-lying lowest unoccupied molecular orbital energy level,which is beneficial for charge transport and injection in organic field-effect transistors(OFETs).Notably,the OFET devices based on all three acceptors achieved impressive electron mobilities,with SN6C10-4F achieving up to 0.73 cm^(2)·V^(-1)·s^(-1),which is one of the highest values among A-D-A type small molecules.In addition,the OSCs device based on PBDB-T:SN6C9-4F exhibited the best power conversion efficiency of 12.07%owing to its optimal morphology and enhanced charge transport.Moreover,the incorporation of SN6C9-4F into the efficient PM6:L8-BO binary system to form ternary OSCs resulted in extended absorption range,enhanced donor crystallization,improved and more balanced charge transport,ultimately leading to an improvement of PCE from 17.78%to 18.32%.This study highlights the potential of developing acceptors with distinct structures from Y-series acceptors to broaden absorption and regulate donor crystallization,providing a novel approach to enhance the PCE of OSCs.
基金supported by the National Natural Science Foundation of China (52173172, 52173171, 21774055)the Natural Science Foundation for Distinguished Young Scholars of Guangdong Province (2021B1515020027)+4 种基金the Shenzhen Science and Technology Innovation Commission (JCYJ202103243104813035,JCYJ20180504165709042)the Open Fund of the State Key Laboratory of Luminescent Materials and Devices (South China University of Technology)China Postdoctoral Science Foundation (2021M700062)the financial support from the Natural Research Foundation of Korea (2016M1A2A2940911, 2015M1A2A2057506)the support of the Guangdong Provincial Key Laboratory Program (2021B1212040001) from the Department of Science and Technology of Guangdong Province。
文摘All-polymer solar cells(all-PSCs) have received extensive attention due to their excellent mechanical robustness and performance stability. However, the power conversion efficiency(PCE) of all-PSCs still lags behind those of organic solar cells(OSCs)based on non-fullerene small molecule acceptors. Herein, we report highly efficient all-PSCs via sequential deposition(SD) with donor and acceptor layers coated sequentially to optimize the film microstructure. Compared with the bulk heterojunction(BHJ)all-PSCs, an optimized morphology with vertical component distribution was achieved for the SD-processed all-PSCs due to the synergistic effect of swelling of polymer films and using additive. Such strategy involves using chlorobenzene as the first layer processing-solvent for polymer donor, chloroform as the second processing-solvent for polymer acceptor with trace 1-chloronaphthalene, efficiently promoting exciton dissociation and charge extraction and reducing trap-assisted recombination.Consequently, over 16% all-PSCs fabricated via SD method was realized for the first time, which is much higher than that(15.2%) of its BHJ counterpart and also among the highest PCEs in all-PSCs. We have further demonstrated the generality of this approach in various all-polymer systems. This work indicates that the SD method can yield excellent all-PSCs and provides a facile approach to fabricating high-performance all-PSCs.
基金the National Natural Science Foundation of China(NSFC,No.21801124)X.G.is grateful to the Shenzhen Science and Technology Innovation Commission(No.JCYJ20180504165709042)We are grateful for the assistance of SUSTech Core Research Facilities.PL and TRPL characterizations were supported by Shenzhen Key Laboratory of Full Spectral Solar Electricity Generation(FSSEG)from the Shenzhen Key Laboratory Project(No.ZDSYS201602261933302).
文摘High-performance,cost-effective hole-transport materials(HTMs)are greatly desired for the commercialization of perovskite solar cells(PVSCs).Herein,two new HTMs,TPA-FO and TPA-PDO,are devised and synthesized,which have a donor-acceptor-donor(D-A-D)type molecule design featuring carbonyl group-functionalized arenes as the acceptor(A)units.The carbonyl group at the central core of HTMs can not only tune frontier molecular orbital(FMO)energy levels and surface wettability,but also can enable efficient surface passivation effects,resulting in reduced recombination loss.When employed as HTMs in inverted PVSCs without using dopant,TPA-FO with one carbonyl group yields a high power conversion efficiency(PCE)of 20.24%,which is among the highest values reported in the inverted PVSCs with dopant-free HTMs.More importantly,the facile one-step synthetic process enables a low cost of 30 USD g^(-1) for TPA-FO,much cheaper than the most studied HTMs used for high-efficiency dopant-free PVSCs.These results demonstrate the potential of D-A-D type molecules with carbonyl group-functionalized arene core in developing the low-cost dopant-free HTMs toward highly efficient PVSCs.
