In Situ Polymer Network in Perovskite Solar Cells Enabled SuperiorMoisture and Thermal Resistance

Perovskite decomposition arising from water permeation and heatinduced crystal expansion is a major obstacle restricting the long-term durability ofperovskite solar cells (PSCs). Herein, a polymerizable methyl acrylate (MCE) wasemployed as dopants in the deposition of perovskite thinfilms. Owing to the in situformed polymer network, the environment moisture can be retained on the perovskitesurface as the formation of a thin layer of perovskite monohydrate to prevent theirdeep penetration and transverse spread, and the heat tolerance of the perovskite wasalso improved because of the anchor structure between Pb2+and-C???O groups andthe agglomeration effect of the polymerized MCE. Moreover, MCE can coordinatewith Pb2+ions and some of them were volatilized during crystallization, resulting inpreferred crystal orientations and suppressed nonradiative recombination. As a result, an excellent efficiency up to 21% withimproved stability of MAPbI3PSC was achieved.

Automated summary

By using polymerizable methyl acrylate (MCE) as a dopant in perovskite thin film deposition, a polymer network is formed to prevent water permeation and crystal expansion, leading to improved stability and heat tolerance of perovskite solar cells (PSCs). Additionally, MCE can coordinate with Pb2+ ions during crystallization, resulting in preferred crystal orientations and suppressed nonradiative recombination.