Designing and fabricating high-performance photovoltaic devices have remained a major challenge in organic solar cell technologies. In this work, the photovoltaic performances of BTBPD-PC61BM system were theoretically...Designing and fabricating high-performance photovoltaic devices have remained a major challenge in organic solar cell technologies. In this work, the photovoltaic performances of BTBPD-PC61BM system were theoretically investigated by means of density functional theory calculations coupled with the Marcus charge transfer model in order to seek novel photovoltaic systems. Moreover, the hole-transfer properties of BTBPD thin-film were also studied by an amorphous cell with 100 BTBPD molecules. Results revealed that the BTBPD- PC61BM system possessed a middle-sized open-circuit voltage of 0.70 V, large short-circuit current density of 16.874 mA/cm2, large fill factor of 0.846, and high power conversion effi- ciency of 10%. With the Marcus model, the charge-dissociation rate constant was predicted to be as fast as 3.079×10^13 s^-1 in the BTBPD-PC61BM interface, which was as 3-5 orders of magnitude large as the decay （radiative and non-radiative） rate constant （108-10^10 s^-1）, indicating very high charge-dissociation efficiency （-100%） in the BTBPD-PC61BM system. Furthermore, by the molecular dynamics simulation, the hole mobility for BTBPD thin-film was predicted to be as high as 3.970× 10^-3 cm^2V^-1s^-1, which can be attributed to its tight packing in solid state.展开更多
（ E）-5,5＇-Bis（ 5-（ benzo[ b ]thiophen- 2-yl ）thiophen-2-yl ）-1,1＇-bis（ 2-ethylhexyl ）-[ 3,3＇-bipyrrolylidene ]- 2,2＇（1H, l＇H）-dione （BTBPD） has been reported by Zhang and co-workers. To further unders...（ E）-5,5＇-Bis（ 5-（ benzo[ b ]thiophen- 2-yl ）thiophen-2-yl ）-1,1＇-bis（ 2-ethylhexyl ）-[ 3,3＇-bipyrrolylidene ]- 2,2＇（1H, l＇H）-dione （BTBPD） has been reported by Zhang and co-workers. To further understand the charge-transporting nature of BTBPD, the density-functional theory （DFF） and the Marcus charge transfer theory were performed. The character of the frontier molecular orbitals, reorganization energies and transfer integrals in different directions were considered in details. The results revealed that the BTBPD has high hole transport efficiency （μ = 0.29 cm2 V-1 s-1 ）. The intermolecular π-π interaction and S...S interaction provide the holes transport channels.展开更多
基金This work was supported by the National Natural Science Foundation of China （No.21373132, No.21502109, No.21603133）, the Education Department of Shmunxi Provincial Government Research Projects （No.16JK1142, No.16JK1134）, and the Scientific Research Foundation of Shaanxi University of Technology for Recruited Talents （No.SLGKYQD2-13, No.SLGKYQD2-10, No.SLGQD14-10）.
文摘Designing and fabricating high-performance photovoltaic devices have remained a major challenge in organic solar cell technologies. In this work, the photovoltaic performances of BTBPD-PC61BM system were theoretically investigated by means of density functional theory calculations coupled with the Marcus charge transfer model in order to seek novel photovoltaic systems. Moreover, the hole-transfer properties of BTBPD thin-film were also studied by an amorphous cell with 100 BTBPD molecules. Results revealed that the BTBPD- PC61BM system possessed a middle-sized open-circuit voltage of 0.70 V, large short-circuit current density of 16.874 mA/cm2, large fill factor of 0.846, and high power conversion effi- ciency of 10%. With the Marcus model, the charge-dissociation rate constant was predicted to be as fast as 3.079×10^13 s^-1 in the BTBPD-PC61BM interface, which was as 3-5 orders of magnitude large as the decay （radiative and non-radiative） rate constant （108-10^10 s^-1）, indicating very high charge-dissociation efficiency （-100%） in the BTBPD-PC61BM system. Furthermore, by the molecular dynamics simulation, the hole mobility for BTBPD thin-film was predicted to be as high as 3.970× 10^-3 cm^2V^-1s^-1, which can be attributed to its tight packing in solid state.
基金the fnancial support from the Ministry of Science and Technology of China(No.09C26212203285)the Project of Science and Technology of Jilin Province(No.201115094)
文摘（ E）-5,5＇-Bis（ 5-（ benzo[ b ]thiophen- 2-yl ）thiophen-2-yl ）-1,1＇-bis（ 2-ethylhexyl ）-[ 3,3＇-bipyrrolylidene ]- 2,2＇（1H, l＇H）-dione （BTBPD） has been reported by Zhang and co-workers. To further understand the charge-transporting nature of BTBPD, the density-functional theory （DFF） and the Marcus charge transfer theory were performed. The character of the frontier molecular orbitals, reorganization energies and transfer integrals in different directions were considered in details. The results revealed that the BTBPD has high hole transport efficiency （μ = 0.29 cm2 V-1 s-1 ）. The intermolecular π-π interaction and S...S interaction provide the holes transport channels.
