Liu Fangyan, Wang Mengye, Liu Xiaolong, Wang Biao, Li Caifu, Liu Chenning, Lin Zhang, Huang Feng
State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials, Sun Yat-Sen University, Guangzhou 510275, China.
State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou 510275, China.
Nano Lett. 2021 Feb 24;21(4):1643-1650. doi: 10.1021/acs.nanolett.0c04299. Epub 2021 Feb 11.
Despite intriguing optoelectronic attributes in solar cells, light-emitting diodes, and photocatalysis, the instability of organic-inorganic perovskites poises a grand challenge for long-term applications. Herein, we report a simple yet robust strategy via light-and-solution treatment to create an organic membrane that effectively passivates CHNHPbI (MAPbI). Specifically, the restructuring of MA is observed on MAPbI in aqueous hydrogen iodide. HIO molecules are generated via the reaction between water and I induced by photocatalysis when MAPbI is illuminated. The hydrogen bonding between HIO molecules at different perovskite particles not only directs the creeplike growth of perovskite particles but also in situ forms a passivating layer firmly anchoring on the perovskite surface with hydrophilic -NH groups tethering to perovskites and hydrophobic -CH moieties exposed to air. Intriguingly, such MA film greatly improves the stability of perovskites against moisture as well as their crystal quality, considerably enhancing the photocatalytic hydrogen evolution rate.
尽管有机-无机钙钛矿在太阳能电池、发光二极管和光催化领域具有引人注目的光电特性，但其不稳定性对长期应用构成了巨大挑战。在此，我们报告了一种通过光和溶液处理的简单而稳健的策略，以创建一种有机膜，该膜能有效钝化CHNHPbI（MAPbI）。具体而言，在碘化氢水溶液中观察到MAPbI上的MA发生了重构。当MAPbI被光照时，通过光催化作用，水与I之间的反应会生成HIO分子。不同钙钛矿颗粒上的HIO分子之间的氢键不仅引导钙钛矿颗粒的蠕变状生长，还原位形成了一个钝化层，该钝化层通过亲水性的-NH基团与钙钛矿相连并牢固地锚定在钙钛矿表面，而疏水性的-CH部分暴露于空气中。有趣的是，这种MA膜极大地提高了钙钛矿对水分的稳定性及其晶体质量，显著提高了光催化析氢速率。
