Crystallization-activated moisture barrier for high-tolerance manufacturing of perovskite solar cells
Yabin Ma, Chao Luo, Changling Zhan, Keli Wang, Jiandong He, Peng Gao, Zhuye Bi, Yingzhuang Ma, Qing Zhao
Abstract
Moisture promotes perovskite crystallization during annealing but only within a narrow humidity range, hindering the stable mass production of perovskite solar cells, especially for formamidinium lead iodide. To overcome this, we integrated a "crystallization-activated moisture barrier" into the perovskite film, which can exist in a liquid state/crystallization phase during the initial annealing to allow moisture to enter and promote crystallization, then migrate upward, and form a dense hydrophobic layer on the film surface to protect the perovskite from high humidity-caused damage. Such a "moisture barrier" enables the manufacturing of perovskite films to be insensitive to a wide range of relative humidity from 20% to over 90%. The barrier also regulates bulk crystallization and passivates surface defects. The crystallization-activated moisture barrier effectively reduces the sensitivity of perovskite films to humidity during annealing, which paves the way for high-tolerance manufacturing of perovskite photovoltaic devices.