Zhang Zhe, Cui Xinyue, Li Miao, Liu Yahui, Li Dawei, Jiang Pengcheng, Bo Zhishan
Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education, Key Laboratory of Eco-environmental Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University Lanzhou 730070 China.
Beijing Key Laboratory of Energy Conversion and Storage Materials, College of Chemistry, Beijing Normal University Beijing 100875 China
RSC Adv. 2019 Nov 29;9(67):39163-39169. doi: 10.1039/c9ra08092a. eCollection 2019 Nov 27.
A fused-ring electron acceptor (FREA) NDIC is designed and synthesized. Inspired by IDIC, NDIC was constructed by replacing the benzene with a naphthalene ring in its core unit. IDIC exhibits an optical bandgap of 1.60 eV and a lower lowest unoccupied molecular orbital (LUMO) energy level of -3.92 eV. In comparison, NDIC displays an optical band gap of 1.72 eV and a higher lying LUMO energy level of -3.88 eV. Due to the higher energy level, inverted devices based on NDIC exhibit a higher open circuit voltage ( ) of 0.90 V, which is much higher than that of IDIC (0.77 V). After a series of optimizations, a power conversion efficiency (PCE) of 9.43% was obtained with a PBDB-T:NDIC blend active layer, in comparison, a PCE of 9.19% was achieved based on IDIC. Our results demonstrate that a tiny variation in the molecular structure could dramatically affect the optical and electrochemical properties, and thus the photovoltaic performance.
设计并合成了一种稠环电子受体（FREA）NDIC。受IDIC启发，NDIC通过在其核心单元中用萘环取代苯环来构建。IDIC的光学带隙为1.60 eV，最低未占据分子轨道（LUMO）能级较低，为-3.92 eV。相比之下，NDIC的光学带隙为1.72 eV，LUMO能级较高，为-3.88 eV。由于能级较高，基于NDIC的倒置器件表现出更高的开路电压（ ），为0.90 V，远高于IDIC的开路电压（0.77 V）。经过一系列优化，PBDB-T:NDIC共混活性层的功率转换效率（PCE）达到了9.43%，相比之下，基于IDIC的PCE为9.19%。我们的结果表明，分子结构的微小变化会显著影响光学和电化学性质，进而影响光伏性能。
