Photocatalytic hydrogen evolution via water splitting was considered as a promising way of solar energy conversion and storage in the past decades. However, the weak visible-light response and fast recombination of electron-hole pairs are still main obstacles to overcome. Herein, a novel 2D/2D Bi₄O₅Br₂/TL-Ti₃C₂ (Thin layer-Ti₃C₂) visible-light photocatalyst was successfully prepared by in-situ synthesis of Bi₄O₅Br₂ nanosheets on the surface of TL-Ti₃C₂ at room temperature. The resulting Bi₄O₅Br₂/TL-Ti₃C₂ exhibits a higher hydrogen evolution activity (83.5 ​μmol·g⁻¹·h⁻¹) than that of pristine Bi₄O₅Br₂ (44.9 ​μmol·g⁻¹·h⁻¹) under visible-light irradiation. The enhanced hydrogen evolution activity of as-prepared photocatalyst mainly attributes to the increased visible light responsiveness and rapid transfer of photo-induced electrons. The strong interaction between TL-Ti₃C₂ and Bi³⁺ in Bi₄O₅Br₂ nanosheets establishes a good electron transfer channel and close contact, which accelerates the transfer of photo-induced electrons from Bi₄O₅Br₂ to Ti₃C₂ and promotes the separation of photo-generated charge carriers, thereby increasing the number of effective photo-induced electrons involved in the hydrogen evolution. This work provides a new insight into the construction of Bi_xO_yBr_z/MXene photocatalyst system, and demonstrated that Ti₃C₂ has excellent application potential in promoting the photocatalytic performance of bismuth-rich bismuth oxyhalides (Bi_xO_yX_z X ​= ​Cl, Br, I).

在过去的几十年中，通过水分解产生的光催化氢被认为是太阳能转化和存储的一种有前途的方式。然而，弱的可见光响应和电子-空穴对的快速重组仍然是要克服的主要障碍。本文通过在表面上原位合成Bi ₄ O ₅ Br ₂纳米片，成功制备了新型2D / 2D Bi ₄ O ₅ Br ₂ / TL-Ti ₃ C ₂（薄层-Ti ₃ C ₂）可见光催化剂。室温下TL-Ti ₃ C ₂的表面。生成的Bi ₄ O₅溴₂ / TL-的Ti ₃ c ^ ₂表现出更高的析氢酶活性（83.5微摩尔·克^-1 ·H ^-1）比原始的Bi ₄ ø ₅溴₂（44.9微摩尔·克^-1 ·H ^{- 1}）在可见光照射下。所制备的光催化剂增强的氢释放活性主要归因于可见光响应性的提高和光诱导电子的快速转移。TL-Ti ₃ C ₂与Bi ³⁺在Bi ₄ O ₅ Br _2中的强相互作用纳米片建立了良好的电子传输通道并紧密接触，从而加速了光致电子从Bi ₄ O ₅ Br ₂到Ti ₃ C ₂的转移，并促进了光生载流子的分离，从而增加了有效光子的数量。 -诱导的电子参与氢的释放。这项工作为Bi _x O _y Br _z / MXene光催化剂体系的构建提供了新的见解，并证明了Ti ₃ C ₂在促进富铋氧化物卤化铋（Bi _xO _y X _z X = Cl，Br，I）。