Zhang Ming, Zhu Lei, Zhou Guanqing, Hao Tianyu, Qiu Chaoqun, Zhao Zhe, Hu Qin, Larson Bryon W, Zhu Haiming, Ma Zaifei, Tang Zheng, Feng Wei, Zhang Yongming, Russell Thomas P, Liu Feng
Frontiers Science Center for Transformative Molecules, In-situ Center for Physical Science, and Center of Hydrogen Science, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China.
Department of Polymer Science and Engineering, University of Massachusetts, Amherst, MA, 01003, USA.
Nat Commun. 2021 Jan 12;12(1):309. doi: 10.1038/s41467-020-20580-8.
The chemical structure of donors and acceptors limit the power conversion efficiencies achievable with active layers of binary donor-acceptor mixtures. Here, using quaternary blends, double cascading energy level alignment in bulk heterojunction organic photovoltaic active layers are realized, enabling efficient carrier splitting and transport. Numerous avenues to optimize light absorption, carrier transport, and charge-transfer state energy levels are opened by the chemical constitution of the components. Record-breaking PCEs of 18.07% are achieved where, by electronic structure and morphology optimization, simultaneous improvements of the open-circuit voltage, short-circuit current and fill factor occur. The donor and acceptor chemical structures afford control over electronic structure and charge-transfer state energy levels, enabling manipulation of hole-transfer rates, carrier transport, and non-radiative recombination losses.
供体和受体的化学结构限制了二元供体-受体混合物活性层所能达到的功率转换效率。在此，通过使用四元共混物，在本体异质结有机光伏活性层中实现了双级联能级排列，从而实现了高效的载流子分裂和传输。组件的化学组成开辟了许多优化光吸收、载流子传输和电荷转移态能级的途径。通过电子结构和形貌优化，同时提高了开路电压、短路电流和填充因子，实现了破纪录的18.07%的功率转换效率。供体和受体的化学结构能够控制电子结构和电荷转移态能级，从而能够操纵空穴转移速率、载流子传输和非辐射复合损失。
