The development of ferroelectric photocatalytic materials with polarization electric field is a key approach to realize the spatial separation and fast transfer of charge carriers in visible-light-driven H₂ evolution. Generally, replacing traditional 3D perovskite-type ferroelectric materials with 2D ferroelectric materials is disregarded as candidates for photocatalysis. Herein a 2D CuInP₂S₆ (CIPS) with room-temperature ferroelectricity (a Curie temperature of around 47 °C) is developed as a new photocatalyst, and 2D/2D heterojunction of CuInP₂S₆ nanosheet/g-C₃N₄ ultrathin flake (CIPS/CN) is constructed to further accelerate charge transfer. Benefitting from the synergetic action of the inner polarization electric field of CIPS and 2D/2D heterojunction, CIPS/CN displays a substantially accelerated charge transfer and significantly enhanced photocatalytic H₂ evolution rate, which is up to 7.6 times by contrast with that of paraelectric-phase CIPS. This work would provide a new platform for the design of 2D ferroelectric photocatalytic system with highly-efficient charge transfer.

开发具有极化电场的铁电光催化材料是在可见光驱动的H ₂演化中实现载流子的空间分离和快速转移的关键方法。通常，以2D铁电材料代替传统的3D钙钛矿型铁电材料不被视为光催化的候选材料。本文开发了具有室温铁电性（居里温度约为47°C）的2D CuInP ₂ S ₆（CIPS）作为新型光催化剂，并且CuInP ₂ S ₆ nanosheet / gC ₃ N _4的2D / 2D异质结。超薄薄片（CIPS / CN）的构造可进一步加速电荷转移。得益于CIPS和2D / 2D异质结的内极化电场的协同作用，CIPS / CN显着加速了电荷转移，并显着提高了光催化H _2的生成速率，与顺电法相比，该速率高达7.6倍。阶段CIPS。这项工作将为设计具有高效电荷转移的二维铁电光催化系统提供一个新的平台。