In recent years, the use of quantum dots (QDs) cocatalysts to improve the hydrogen evolution activity from the water splitting of photocatalysts has become a popular research topic. Herein, we successfully prepared a novel 0 dimension/2 dimension (0D/2D) heterojunction nanocomposite (denoted Ag₂S quantum dots (QDs)/g-C₃N₄) with excellent photocatalytic performance by anchoring the Ag₂S QDs cocatalyst on the surface of g-C₃N₄ through a self-assembly strategy. Ag₂S QDs with an average particle size of approximately 5.8 nm were uniformly and tightly modified on g-C₃N₄. The Ag₂S QDs/g-C₃N₄ composite with 0.5 wt% Ag₂S QDs loading achieved the highest hydrogen evolution rate of 471.1 μmol·g⁻¹·h⁻¹ with an apparent quantum efficiency (AQE) of 1.48% at 405 nm. Such remarkable hydrogen evolution activity far exceeded that of undoped g-C₃N₄ and Ag₂S nanoparticles (NPs)/g-C₃N₄. Moreover, it was 2.04 times the activity of Pt/g-C₃N₄ with Pt as the cocatalyst. The enhanced photocatalytic performance was attributed to the energy band broadening of Ag₂S QDs caused by the quantum size effect and the convenient and effective charge transfer between g-C₃N₄ and Ag₂S QDs cocatalysts. The mechanism underlying the enhanced photocatalytic H₂ evolution activity was further proposed. This study demonstrates that semiconductor-based quantum dots are strong candidates for excellent cocatalysts in photocatalysis.

近年来，利用量子点（QDs）助催化剂来提高光催化剂分解水的析氢活性已成为一个热门的研究课题。在此，我们通过将 Ag ₂ S QDs 助催化剂锚定在表面上，成功制备了具有优异光催化性能的新型 0 维/2 维 (0D/2D) 异质结纳米复合材料（表示为 Ag ₂ S 量子点（QDs）/gC ₃ N ₄）gC ₃ N ₄通过自组装策略。平均粒径约为 5.8 nm 的Ag ₂ S QD 在 gC ₃ N ₄上均匀且紧密地改性。银₂S QDs/gC ₃ N ₄复合材料与0.5 wt% Ag ₂ S QDs 负载实现了最高的析氢速率471.1 μmol·g ^-1 ·h ^-1，在405 nm 处的表观量子效率（AQE）为1.48%。这种显着的析氢活性远远超过未掺杂的 gC ₃ N ₄和 Ag ₂ S 纳米粒子 (NPs)/gC ₃ N _{4 的}。此外，它是Pt作为助催化剂的Pt/gC ₃ N ₄活性的2.04倍。增强的光催化性能归因于 Ag ₂的能带展宽由量子尺寸效应和 gC ₃ N ₄和 Ag ₂ S QD 助催化剂之间方便有效的电荷转移引起的S QD。基础的光催化增强H中的机构₂演化活性进一步提出。这项研究表明，基于半导体的量子点是光催化中优异助催化剂的有力候选者。