In Situ Photogenerated Radicals of Hydroxyl Substituted Pyrene ‐Based Triphenylamines with Enhanced Transport and Free Doping/Post‐Oxidation for Efficient Perovskite Solar Cells

The pyrene-based HTMs exhibit excellent performance in PSCs with a short-circuit current density (JSC) of 24.71 mA  cm−2, open-circuit voltage (Voc) of 1.18 V, and a fill factor (FF) of 80.41%, with the highest PCE of 23.5%, an average PCE of 23.44%, which is the highest PCE reported to-date for PSCs with a pyrene-core based HTM. AbstractThe high-performance hole transporting material (HTM) is one of the most important components for the perovskite solar cells (PSCs) in promoting power conversion efficiency (PCE). However, the low conductivity of HTMs and their additional requirements for doping and post-oxidation greatly limits the device performance. In this work, three novel pyrene-based derivatives containing methoxy-substituted triphenylamines units (PyTPA,PyTPA-OH andPyTPA-2OH) are designed and synthesized, where different numbers of hydroxyl groups are connected at the 2- or 2,7-positions of the pyrene core. These hydroxyl groups at the 2- or 2,7-positions of pyrene play a significantly role to enhance the intermolecular interactions that are able to generate in situ radicals with the assistance of visible light irradiation, resulting in enhanced hole transferring ability, as well as an enhanced conductivity and suppressed recombination. These pyrene-core based HTMs exhibit excellent performance in PSCs, which possess a higher PCE than those control devices using the traditional spiro-OMeTAD as the HTM. The best performance can be found in the devices withPyTPA-2OH....

Source: Small - April 3, 2024 Category: Nanotechnology Authors: Xiaohui Wang, Zhixin Xie, Rongxin Wang, Ye Xiao, Kai Yan, Yu Zhao, Rui Lin, Carl Redshaw, Yonggang Min, Xinhua Ouyang, Xing Feng Tags: Research Article Source Type: research