理论研究BBPQ-PC61BM体系的光伏性质

探索和制备具有高能量转换效率（PCE）的有机太阳能电池体系是有机电子学的重要领域和研究热点。本文利用量子化学和分子动力学计算结合Marcus-Hush电荷传输模型理论研究了BBPQ-PC₆₁BM（BBPQ：7，12-二（（三异丙基甲硅烷基）乙炔基）苯并（g）吡啶并（2’，3’：5，6）吡嗪并（2，3-b）喹喔啉-2（1H）-酮；PC₆₁BM：（6，6）苯基-C₆₁-丁酸甲酯）体系的光伏性质。结果表明，BBPQ-PC₆₁BM体系具有相当大的开路电压（1.22 V）、高的填充因子（0.90）和高的光电转换效率（9%-10%）。此外，本文研究还发现BBPQ-PC₆₁BM体系拥有中等大小的激子结合能（0.607 eV），但相对较小的激子分离和电荷复合重组能（0.345和0.355 eV）。借助于一个简单的分子复合物模型，本文预测BBPQ-PC₆₁BM体系的激子解离速率常数k_dis高达1.775×10¹³ s^-1，而预测的电荷复合速率常数k_rec相当小（<1.0 s^-1），这表明在BBPQ-PC₆₁BM相界面上，激子解离效率非常高。总之，理论研究表明，BBPQ-PC₆₁BM是一个非常有前途的有机太阳能电池候选体系，值得实验上做出进一步研究。

Theoretical Investigation on Photovoltaic Properties of the BBPQ-PC61BM System

Exploring and fabricating organic solar cell devices with the high power conversion efficiency (PCE) has kept a major challenge and hot topic in organic electronics research. In this study, we have used quantum chemical and molecular dynamics calculations in conjunction with the Marcus-Hush charge transfer model to investigate the photovoltaic properties of BBPQ-PC₆₁BM. The results revealed that the BBPQ-PC₆₁BM (BBPQ:7,12-bis((triisopropylsilyl)-ethynyl)benzo(g)pyrido(2',3':5,6)pyrazino(2,3-b)quinoxalin-2(1H)-one; PC₆₁BM:(6, 6)-phenyl-C₆₁-butyric acid methyl ester) system theoretically possesses a large open-circuit voltage (1.22 V), high fill factor (0.90), and high PCE of 9%-10%. The calculations also reveal that the BBPQ-PC₆₁BM system has a medium-sized exciton binding energy (0.607 eV), with relatively small reorganization energies (0.345 and 0.355 eV) for its exciton-dissociation and charge-recombination processes. Based on a simplified molecular complex, the exciton dissociation rate constant, k_dis, was estimated to be as large as 1.775×10¹³ s^-1 at the BBPQPC₆₁BM interface. In contrast, the charge-recombination rate constant, k_rec, was very small under the same conditions (<1.0 s^-1), which indicated a rapid and efficient exciton-dissociation process at the donor-acceptor interface. Overall, our calculations show that the BBPQ-PC₆₁BM system is a very promising organic solar cell system that is worthy of further research.