Huo Xiaonan, Sun Weiwei, Wang Kexiang, Liu Weifeng, Yin Ran, Sun Yansheng, Gao Yukun, You Tingting, Yin Penggang
School of Chemistry, Beihang University, Beijing 100191, P. R. China.
Engineering Research Center of High-Performance Polymer and Molding Technology, Ministry of Education, Qingdao University of Science and Technology, Qingdao 266042, P. R. China.
ACS Appl Mater Interfaces. 2023 Feb 9. doi: 10.1021/acsami.2c21226.
Due to the advantages of low cost and good thermal stability, all-inorganic CsPbIBr carbon-based perovskite solar cells (C-PSCs) without a hole transport layer have been rapidly developed in recent years. While the carbon electrode is in direct contact with the CsPbIBr film, higher requirements are placed on the defects and energy level arrangement of the CsPbIBr layer, which leads to the relatively low photoelectric conversion efficiency (PCE) of C-PSCs. Herein, propylamine hydrobromide (PABr) and its derivative 3-bromopropylamine hydrobromide (3Br-PABr) were used to passivate the surface defects of CsPbIBr C-PSCs for the first time. The results show that passivation molecules are modulated by the substituent effect, leading to a stronger interaction between amino groups and uncoordinated Pb ions, which facilitates a better passivation effect of 3Br-PABr. In addition, 3Br-PABr promotes the gradient arrangement of energy levels while passivating surface defects, which accelerates the rapid extraction of holes. After the passivation by PABr and 3Br-PABr, the PCE of HTL-free CsPbIBr C-PSCs increased from 12.15% for the control device to 13.15 and 14.04%, respectively, which are among the highest reported values of CsPbIBr C-PSCs.
由于具有低成本和良好热稳定性的优点，近年来不含空穴传输层的全无机CsPbIBr碳基钙钛矿太阳能电池（C-PSCs）得到了迅速发展。当碳电极与CsPbIBr薄膜直接接触时，对CsPbIBr层的缺陷和能级排列提出了更高的要求，这导致C-PSCs的光电转换效率（PCE）相对较低。在此，首次使用丙胺氢溴酸盐（PABr）及其衍生物3-溴丙胺氢溴酸盐（3Br-PABr）对CsPbIBr C-PSCs的表面缺陷进行钝化。结果表明，钝化分子受取代基效应的调节，导致氨基与未配位的Pb离子之间的相互作用更强，这有利于3Br-PABr具有更好的钝化效果。此外，3Br-PABr在钝化表面缺陷的同时促进了能级的梯度排列，加速了空穴的快速提取。经PABr和3Br-PABr钝化后，无HTL的CsPbIBr C-PSCs的PCE分别从对照器件的12.15%提高到13.15%和14.04%，这是CsPbIBr C-PSCs报道的最高值之一。
