Potassium stabilization of methylammonium lead bromide perovskite for robust photocatalytic H₂ generation

Abstract

Various optoelectronic applications of organic inorganic hybrid lead halide perovskites are challenged by their stability. The photocatalytic stability of lead halide perovskites are so low that chemical stabilizer such as H3PO2 are required in their applications. We report a postsynthesis potassium stabilization on methylammonium lead bromide (MAPbBr3) to form K‐MAPbBr3 by doping K cation and depositing KBr layers. In absence of any stabilizer, this stable K‐MAPbBr3 perovskite can exhibit an unprecedented high photostability even after 200 hours continuous photocatalytic H2 generation. Impressively, the K‐MAPbBr3 cocatalyzed with Mo3S132− nanoclusters achieves a high apparent quantum efficiency up to 18.3% at 450 nm for photocatalytic H2 generation. The mechanism study reveals that the photogeneration of Pb0 and Br0 defects are effectively inhibited in K‐MAPbBr3, which makes it a robust photocatalyst for H2 generation. These findings will inspire the development of stable organic‐inorganic hybrid perovskites for photocatalysis and other optoelectronic applications.

Recent progress in cathode interlayer materials for non‐fullerene organic solar cells

“…Recently, it has been reported that potassium doping in methylammonium lead bromide (MAPbBr 3 ) demonstrates higher photostability. 139 Cheng et al 140 treated ZnO with potassium hydroxide (KOH) and found that the difference in binding energy increased between NF acceptor and donor compared to without-treated ZnO. As a result, acceptor-rich moieties are concentrated at the cathode side while donor-rich moieties near to anode, verified by time-of-flight secondary ion mass spectrometry (Figure 6A).…”

“…The device maintained 81% of PCE after 1000 h storage in nitrogen glove box compared to 60% in bare ZnO. Recently, it has been reported that potassium doping in methylammonium lead bromide (MAPbBr 3 ) demonstrates higher photostability 139 . Cheng et al 140 treated ZnO with potassium hydroxide (KOH) and found that the difference in binding energy increased between NF acceptor and donor compared to without‐treated ZnO.…”

Photoredox Organic Synthesis Employing Heterogeneous Photocatalysts with Emphasis on Halide Perovskite

“…Surface engineering or chemical modifications of perovskite NCs are under active exploration to address these concerns, for example, water‐resistant perovskite, (HDA) 2 PbI 4 , for reactions in polar solvents, capping ligand exchanged perovskite nanocrystals for higher photocatalytic reactivity, suitable band tuning of perovskites with higher stability, and improved reactivity and selectivity for C−C, C−N, and C−O bond formations . Strategies focusing on stability have been some of the major exploration routes in perovskite photovoltaics and perovskite‐catalyzed H 2 evolution or CO 2 reduction reactions, and although above similar challenges have been explored in photocatalytic organic synthesis, they have received relatively little attention. More and essential endeavors towards improving the perovskite catalyst's stability, reactivity, and selectivity are required.…”

Recent Progress in Engineering Metal Halide Perovskites for Efficient Visible‐Light‐Driven Photocatalysis

“…Various metals, transition‐metal carbides, transition‐metal sulfides, and graphene materials, have been applied as cocatalysts for the modification of MHPs to tune the reactions kinetics and charge‐carrier transfer of the HER. The group of Huang followed up their work by reporting a facile light‐assisted halide‐exchange method to fabricate the mixed‐halide perovskite MAPbBr 3− x I x , which possessed a band gap funnel structure (Figure c) .…”