Recently, lead halide perovskites (LHPs) have been intensively investigated for use as photoelectrodes in photoelectrochemical (PEC) water splitting systems, and PEC water splitting systems with LHP electrodes have shown outstanding solar-to-hydrogen (STH) efficiencies. Despite the significant role of large-scale deployment for practical commercialization, the fabrication of large-area LHP photoelectrodes is rarely investigated in the field of PEC water splitting. Herein, we present a strategy involving immersing an as-coated LHP film in an antisolvent containing cyclohexylammonium iodide (CHAI) for the fabrication of high-quality large-size LHP films for use in unbiased PEC water splitting. CHAI molecules accelerate nucleation kinetics by participating in the formation of an intermediate phase, resulting in uniform high-crystallinity LHP films. Furthermore, CHAI molecules effectively passivate grain boundaries, thereby increasing the photocurrent density and onset potential of PEC devices. Consequently, parallelly illuminated coplanar LHP-based photoelectrodes with dimensions of 8 cm × 8 cm could be stably operated without any applied bias, and they exhibited a record-high STH efficiency of 9.89% and a T₈₀ (the time at which the photocurrent density drops to 80% of its initial value) of 24 h. The hydrogen production rate of our device was 145.56 μmol h⁻¹ cm⁻², which is highly comparable with previously reported values of state-of-the-art unassisted PEC devices.

中文翻译：

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用于大规模太阳能制氢的大面积全钙钛矿共面光电极

最近，人们对卤化铅钙钛矿（LHP）用作光电化学（PEC）水分解系统中的光电极进行了深入研究，并且采用LHP电极的PEC水分解系统表现出了出色的太阳能制氢（STH）效率。尽管大规模部署对于实际商业化具有重要作用，但大面积 LHP 光电极的制造在 PEC 水分解领域却很少被研究。在此，我们提出了一种策略，涉及将涂覆后的 LHP 薄膜浸泡在含有环己基碘化铵 (CHAI) 的反溶剂中，以制造用于无偏 PEC 水分解的高质量大尺寸 LHP 薄膜。 CHAI 分子通过参与中间相的形成加速成核动力学，从而形成均匀的高结晶度 LHP 薄膜。此外，CHAI分子有效钝化晶界，从而增加PEC器件的光电流密度和起始电位。因此，尺寸为 8 cm × 8 cm 的平行照明共面 LHP 光电极可以在没有任何外加偏压的情况下稳定工作，并且表现出创纪录的高 STH 效率（9.89%）和 T80（光电流密度下降到其初始值的 80%) 24 小时。我们的装置的氢气生产率为 145.56 μmol h–1 cm-2，与之前报道的最先进的无辅助 PEC 装置的值高度可比。