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

Abstract

Perovskite decomposition arising from water permeation and heat induced crystal expansion is a major obstacle restricting the long-term durability of perovskite solar cells (PSCs). Herein, a polymerizable methyl acrylate (MCE) was employed as dopants in the deposition of perovskite thin films. Owing to the in situ formed polymer network, the environment moisture can be retained on the perovskite surface as the formation of a thin layer of perovskite monohydrate to prevent their deep penetration and transverse spread, and the heat tolerance of the perovskite was also improved because of the anchor structure between Pb 2+ and −CO groups and the agglomeration effect of the polymerized MCE. Moreover, MCE can coordinate with Pb 2+ ions and some of them were volatilized during crystallization, resulting in preferred crystal orientations and suppressed nonradiative recombination. As a result, an excellent efficiency up to 21% with improved stability of MAPbI 3 PSC was achieved.

面向高稳定性太阳能电池开发的卤化物钙钛矿稳定 性提升策略

“…Recently, polymer networks formed by small-molecule crosslinking are utilized to improve device stability. Xu et al [61] utilized a polymerizable methyl acrylate (MCE) to assist the crystallization of perovskite, achieving preferred crystal orientations and high-quality perovskite films. Besides, the residual MCE at grain boundaries and interfaces cross-link with each other to form hydrophobic polymer networks, which significantly improves the structural stability and moisture resistance of perovskite, as shown in Fig.…”

Hydrophobic–Hydrophilic Block Copolymer Mediated Tuning of Halide Perovskite Photosensitive Device Stability and Efficiency

“…7 In addition, the presence of polymer can alter the crystallization kinetics and retard the growth of perovskite grains leading to alteration in the grain size. 8,9 Over the years, several research groups have attempted to utilize polymers containing functional groups with the potential of interacting with perovskite precursors. Several works have been reported using different polymer additives such as polystyrene (PS), polyethylene glycol (PEG), polymethyl methacrylate (PMMA), polyethylenimine (PEI), and polyvinylpyrrolidone (PVP) which inherently differ not only in terms of their hydrophobicity but also in the interaction mechanism with the perovskite precursors owing to the difference in polarity.…”

“…Due to their high molecular weights, the polymers do not evaporate during the annealing of the perovskite films and can effectively passivate the defect centers present at the grain boundaries and interface of the perovskite film . In addition, the presence of polymer can alter the crystallization kinetics and retard the growth of perovskite grains leading to alteration in the grain size. , Over the years, several research groups have attempted to utilize polymers containing functional groups with the potential of interacting with perovskite precursors. Several works have been reported using different polymer additives such as polystyrene (PS), polyethylene glycol (PEG), polymethyl methacrylate (PMMA), polyethylenimine (PEI), and polyvinylpyrrolidone (PVP) which inherently differ not only in terms of their hydrophobicity but also in the interaction mechanism with the perovskite precursors owing to the difference in polarity. − Our previous work confirms the ability of PS chains to interact with both perovskite precursor salts leading to the formation of a trilayer nanoscale architecture in PS-MAPbI 3 films.…”

Surface polymerization of melamine resin on a perovskite: enhancing the efficiency and stability of solar cells

“…[13][14][15][16][17][18] However, interface layers composed of small molecules typically exhibit weak intermolecular interactions, rendering them vulnerable to performance degradation under conditions such as device operation or accelerated aging. In contrast, polymer interface materials, [19][20][21][22][23][24][25] particularly cross-linked network polymers, [26][27][28] are expected to possess superior mechanical and chemical stability and adhere more rmly to the perovskite surface, resulting in reduced susceptibility to performance degradation.…”