Two novel asymmetric organic small molecules of IT(2FBT-T3Cz)_2and IT(2FBT-TT3Cz)_2with an indenothiophene(IT)central donor core,fluorinated benzothiadiazole(2FBT)as acceptor and 3-carbazole(Cz)unit as terminal group ...Two novel asymmetric organic small molecules of IT(2FBT-T3Cz)_2and IT(2FBT-TT3Cz)_2with an indenothiophene(IT)central donor core,fluorinated benzothiadiazole(2FBT)as acceptor and 3-carbazole(Cz)unit as terminal group were designed and synthesized as the donor materials in organic solar cells(OSCs).The thermal,optical absorption,electrochemical property,hole–electron mobility,film morphology were thoroughly studied.Using PC_(71)BM as an electron acceptor,without any additive and thermal annealing(TA)treatment,the IT(2FBT-T3Cz)_2-based cells showed a promising power conversion efficiency(PCE)of5.81%and the IT(2FBT-TT3Cz)_2-based cells exhibited a PCE of 4.39%.Our results demonstrate that the IT-based asymmetric small molecules can be developed as a promising class of donor materials for highperformance OSCs.展开更多
The non-fully conjugated polymer as a new class of acceptor materials has shown some advantages over its small molecular counterpart when used in photoactive layers for all-polymer solar cells(all-PSCs),despite a low ...The non-fully conjugated polymer as a new class of acceptor materials has shown some advantages over its small molecular counterpart when used in photoactive layers for all-polymer solar cells(all-PSCs),despite a low power conversion efficiency(PCE)caused by its narrow absorption spectra.Herein,a novel non-fully conjugated polymer acceptor PFY-2TS with a low bandgap of~1.40 eV was developed,via polymerizing a largeπ-fused small molecule acceptor(SMA)building block(namely YBO)with a non-conjugated thioalkyl linkage.Compared with its precursor YBO,PFY-2TS retains a similar low bandgap but a higher LUMO level.Moreover,compared with the structural analog of YBO-based fully conjugated polymer acceptor PFY-DTC,PFY-2TS shows a similar absorption spectrum and electron mobility,but significantly different molecular crystallinity and aggregation properties,which results in optimal blend morphology with a polymer donor PBDB-T and physical processes of the device in all-PSCs.As a result,PFY-2TS-based all-PSCs achieved a PCE of 12.31%with a small energy loss of 0.56 eV enabled by the reduced non-radiative energy loss(0.24 eV),which is better than that of 11.08%for the PFY-DTC-based ones.Our work clearly demonstrated that non-fully conjugated polymers as a new class of acceptor materials are very promising for the development of high-performance all-PSCs.展开更多
A series of N-dioctylmethyl-2,7-carbazole-alt-5,7-bis（thiophen-2-yl）-2,3-biphenylthieno[3,4-b]pyrazine （PCz-3ThPz-Ph） co- polymeric derivatives appending various donor units in two phenyl rings, namely, PCz-3ThPz-...A series of N-dioctylmethyl-2,7-carbazole-alt-5,7-bis（thiophen-2-yl）-2,3-biphenylthieno[3,4-b]pyrazine （PCz-3ThPz-Ph） co- polymeric derivatives appending various donor units in two phenyl rings, namely, PCz-3ThPz-PhTh, PCz-3ThPz-PhF1, PCz-3ThPz-PhCz, and PCz-3ThPz-PhTpa were synthesized and characterized. The effect of these appending donor units, e.g., thiophene （Th）, fluorene （F1）, carbazole （Cz）, and triarylamine （Tpa）, was investigated on dispersible, optical, electrochemical, and photovoltaic properties for their polymers. The copolymers of PCz-3ThPz-PhCz and PCz-3ThPz-PhTpa containing Cz or Tpa units exhibited higher short-circuit current density （Jsc） and power conversion efficiency （PCE） in their bulk heterojunction polymeric solar cells. The highest PCE of 1.66% and Jsc of 7.16 mA cm-2 were obtained in a device with the PCz-3ThPz-PhCz/PC61BM blend under AM 1.5 G irradiation （100 mW cm 2）; these values are 1.78 and 1.59 times higher than the corresponding values for the PCz-3ThPz-Ph-based device. When PC61BM was placed by PC71BM, the PCz-3ThPz-PhCz-based device displayed an enhanced PCE of 2.98% and a Jsc of 10.88 mA cm-2. This work demonstrated that appending additional hole-transporting units of Cz and Tpa into the side-chain of a polymer with a D-A backbone can significantly enhance the photovoltaic performance of their resultant polymers.展开更多
In order to boost power conversion efficiency(PCE) and operation stability of organic solar cells(OSCs),we propose a new idea of phase junction materials(PJMs) used as a photoactive layer component to improve device p...In order to boost power conversion efficiency(PCE) and operation stability of organic solar cells(OSCs),we propose a new idea of phase junction materials(PJMs) used as a photoactive layer component to improve device performance and stability.For this purpose,a novel PJM of H-TRC8 based on rhodanine unit was designed with a conjugated AH-D-A framework.Here,AH is a hydrogen-donating electron acceptor unit,D-A is an electron donor-acceptor unit.It is found that H-TRC8 has a good carriertransporting ability,as well as definite hydrogen-bond and D-A interaction with donor/acceptor materials.While H-TRC8 is added into the PBDB-T/PC60BM blend film with 1.0 vol% DIO(1,8-diiodooctane),the resulting blend film exhibited an enhanced absorption and improved morphology.The intermolecular hydrogen bond between H-TRC8 and PBDB-T plays an important role for them,which is confirmed via FT-IR spectra and 2D 1H NMR.As a result,the PBDB-T/PC60BM-based devices with 1.25 wt%H-TRC8 and 1.0 vol% DIO exhibit a significantly improved PCE of 8.06%,which is increased by 20.6% in comparison to that in the binary devices with 1.0 vol% DIO only(PCE=6.68%).Furthermore,the device stability is significantly enhanced with only 43% PCE roll-off at 150℃ for 120 h.This work indicates that AH-D-A-type PJMs are promising photovoltaic materials used as photoactive-layer components to achieve high-performance fullerene OSCs with high device stability.展开更多
Signal processing has entered the era of big data,and improving processing efficiency becomes crucial.Traditional computing architectures face computational efficiency limitations due to the separation of storage and ...Signal processing has entered the era of big data,and improving processing efficiency becomes crucial.Traditional computing architectures face computational efficiency limitations due to the separation of storage and computation.Array circuits based on multi-conductor devices enable full hardware convolutional neural networks(CNNs),which hold great potential to improve computational efficiency.However,when processing large-scale convolutional computations,there is still a significant amount of device redundancy,resulting in low computational power consumption and high computational costs.Here,we innovatively propose a memristor-based in-situ convolutional strategy,which uses the dynamic changes in the conductive wire,doping area,and polarization area of memristors as the process of convolutional operations,and uses the time required for conductance switching of a single device as the computation result,embodying convolutional computation through the unique spiked digital signal of the memristor.Our strategy reasonably encodes complex analog signals into simple digital signals through a memristor,completing the convolutional computation at the device level,which is essential for complex signal processing and computational efficiency improvement.Based on the implementation of device-level convolutional computing,we have achieved feature recognition and noise filtering for braille signals.We believe that our successful implementation of convolutional computing at the device level will promote the construction of complex CNNs with large-scale convolutional computing capabilities,bringing innovation and development to the field of neuromorphic computing.展开更多
基金supported by the National Natural Science Foundation of China (51403178, 51573154)the Project of Hunan Natural Science Foundation (2018JJ2391, 2015JJ3113)the Scientific Research Fund of Hunan Provincial Education Department (14C1099, YB2015B025, 13A102)
文摘Two novel asymmetric organic small molecules of IT(2FBT-T3Cz)_2and IT(2FBT-TT3Cz)_2with an indenothiophene(IT)central donor core,fluorinated benzothiadiazole(2FBT)as acceptor and 3-carbazole(Cz)unit as terminal group were designed and synthesized as the donor materials in organic solar cells(OSCs).The thermal,optical absorption,electrochemical property,hole–electron mobility,film morphology were thoroughly studied.Using PC_(71)BM as an electron acceptor,without any additive and thermal annealing(TA)treatment,the IT(2FBT-T3Cz)_2-based cells showed a promising power conversion efficiency(PCE)of5.81%and the IT(2FBT-TT3Cz)_2-based cells exhibited a PCE of 4.39%.Our results demonstrate that the IT-based asymmetric small molecules can be developed as a promising class of donor materials for highperformance OSCs.
基金supported by the National Key Research and Development Program of China(2022YFB3603802)the National Natural Science Foundation of China(62374033)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(2021ZZ129)。
基金This work was supported by the Swedish Research Council(2015-04853,2016-06146,2019-04683)the Swedish Research Council Formas,the Knut and Alice Wallenberg Foundation(2017.0186,2016.0059)+5 种基金the Open Fund of the State Key Laboratory of Luminescent Materials and Devices(South China University of Technology,2020-skllmd-07)E.Moons thanks the Swedish Energy Council for financial support(project 48598-1)W.Su thanks the project funded by China Postdoctoral Science Foundation(2020M673054)Postdoctoral Fund of Jinan University,and the National Natural Science Foundation of China(22005121)L.Hou thanks the National Natural Science Foundation of China(61774077)Support from Sino-Danish Centre for Education and Research is fully acknowledged by D.Yu.Y.Li thanks the financial support from the Science and Technology Program of Shanxi Province(2019JQ-244).
文摘The non-fully conjugated polymer as a new class of acceptor materials has shown some advantages over its small molecular counterpart when used in photoactive layers for all-polymer solar cells(all-PSCs),despite a low power conversion efficiency(PCE)caused by its narrow absorption spectra.Herein,a novel non-fully conjugated polymer acceptor PFY-2TS with a low bandgap of~1.40 eV was developed,via polymerizing a largeπ-fused small molecule acceptor(SMA)building block(namely YBO)with a non-conjugated thioalkyl linkage.Compared with its precursor YBO,PFY-2TS retains a similar low bandgap but a higher LUMO level.Moreover,compared with the structural analog of YBO-based fully conjugated polymer acceptor PFY-DTC,PFY-2TS shows a similar absorption spectrum and electron mobility,but significantly different molecular crystallinity and aggregation properties,which results in optimal blend morphology with a polymer donor PBDB-T and physical processes of the device in all-PSCs.As a result,PFY-2TS-based all-PSCs achieved a PCE of 12.31%with a small energy loss of 0.56 eV enabled by the reduced non-radiative energy loss(0.24 eV),which is better than that of 11.08%for the PFY-DTC-based ones.Our work clearly demonstrated that non-fully conjugated polymers as a new class of acceptor materials are very promising for the development of high-performance all-PSCs.
基金supported by the major program for cultivation of the National Natural Science Foundation of China(91233112)the National Natural Science Foundation of China(21172187,50973093,51403178)+3 种基金the Innovation Group and Xiangtan Joint Project of the Hunan Natural Science Foundation(12JJ7002,12JJ8001)the Scientific Research Fund of Hunan Provincial Education Department(11CY023,12B123)the Open Fund of the State Key Laboratory of Luminescent Materials and Devices(South China University of Technology,No.2014-skllmd-10)the Postgraduate Science Foundation for Innovation in Hunan Province(CX2014B257,CX2011B263)
文摘A series of N-dioctylmethyl-2,7-carbazole-alt-5,7-bis（thiophen-2-yl）-2,3-biphenylthieno[3,4-b]pyrazine （PCz-3ThPz-Ph） co- polymeric derivatives appending various donor units in two phenyl rings, namely, PCz-3ThPz-PhTh, PCz-3ThPz-PhF1, PCz-3ThPz-PhCz, and PCz-3ThPz-PhTpa were synthesized and characterized. The effect of these appending donor units, e.g., thiophene （Th）, fluorene （F1）, carbazole （Cz）, and triarylamine （Tpa）, was investigated on dispersible, optical, electrochemical, and photovoltaic properties for their polymers. The copolymers of PCz-3ThPz-PhCz and PCz-3ThPz-PhTpa containing Cz or Tpa units exhibited higher short-circuit current density （Jsc） and power conversion efficiency （PCE） in their bulk heterojunction polymeric solar cells. The highest PCE of 1.66% and Jsc of 7.16 mA cm-2 were obtained in a device with the PCz-3ThPz-PhCz/PC61BM blend under AM 1.5 G irradiation （100 mW cm 2）; these values are 1.78 and 1.59 times higher than the corresponding values for the PCz-3ThPz-Ph-based device. When PC61BM was placed by PC71BM, the PCz-3ThPz-PhCz-based device displayed an enhanced PCE of 2.98% and a Jsc of 10.88 mA cm-2. This work demonstrated that appending additional hole-transporting units of Cz and Tpa into the side-chain of a polymer with a D-A backbone can significantly enhance the photovoltaic performance of their resultant polymers.
基金financial support from the National Natural Science Foundation of China(Nos.51673031,51573154)the Major Program of the Natural Science Research of Jiangsu Higher Education Institutions(No.18KJA480001)+3 种基金the Top-Notch Academic Programs Project(TAPP)for Polymeric Materials Science and Technologythe Priority Academic Program Development(PAPD)of Jiangsu Higher Education InstitutionsJiangsu Provincial Talents Project of High-Level Innovation and Entrepreneurshipthe Talent Project of Jiangsu Specially-Appointed Professor。
文摘In order to boost power conversion efficiency(PCE) and operation stability of organic solar cells(OSCs),we propose a new idea of phase junction materials(PJMs) used as a photoactive layer component to improve device performance and stability.For this purpose,a novel PJM of H-TRC8 based on rhodanine unit was designed with a conjugated AH-D-A framework.Here,AH is a hydrogen-donating electron acceptor unit,D-A is an electron donor-acceptor unit.It is found that H-TRC8 has a good carriertransporting ability,as well as definite hydrogen-bond and D-A interaction with donor/acceptor materials.While H-TRC8 is added into the PBDB-T/PC60BM blend film with 1.0 vol% DIO(1,8-diiodooctane),the resulting blend film exhibited an enhanced absorption and improved morphology.The intermolecular hydrogen bond between H-TRC8 and PBDB-T plays an important role for them,which is confirmed via FT-IR spectra and 2D 1H NMR.As a result,the PBDB-T/PC60BM-based devices with 1.25 wt%H-TRC8 and 1.0 vol% DIO exhibit a significantly improved PCE of 8.06%,which is increased by 20.6% in comparison to that in the binary devices with 1.0 vol% DIO only(PCE=6.68%).Furthermore,the device stability is significantly enhanced with only 43% PCE roll-off at 150℃ for 120 h.This work indicates that AH-D-A-type PJMs are promising photovoltaic materials used as photoactive-layer components to achieve high-performance fullerene OSCs with high device stability.
基金the financial support from the National Natural Science Foundation of China(62374033,and 62304039)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(2021ZZ129)the Postdoctoral Fellowship Program(Grade B)of China Postdoctoral Science Foundation(GZB20240155)。
文摘Signal processing has entered the era of big data,and improving processing efficiency becomes crucial.Traditional computing architectures face computational efficiency limitations due to the separation of storage and computation.Array circuits based on multi-conductor devices enable full hardware convolutional neural networks(CNNs),which hold great potential to improve computational efficiency.However,when processing large-scale convolutional computations,there is still a significant amount of device redundancy,resulting in low computational power consumption and high computational costs.Here,we innovatively propose a memristor-based in-situ convolutional strategy,which uses the dynamic changes in the conductive wire,doping area,and polarization area of memristors as the process of convolutional operations,and uses the time required for conductance switching of a single device as the computation result,embodying convolutional computation through the unique spiked digital signal of the memristor.Our strategy reasonably encodes complex analog signals into simple digital signals through a memristor,completing the convolutional computation at the device level,which is essential for complex signal processing and computational efficiency improvement.Based on the implementation of device-level convolutional computing,we have achieved feature recognition and noise filtering for braille signals.We believe that our successful implementation of convolutional computing at the device level will promote the construction of complex CNNs with large-scale convolutional computing capabilities,bringing innovation and development to the field of neuromorphic computing.
