Photocatalytic selective oxidation of alcohols into high value-added carbonyl compounds accompanied by producing hydrogen peroxide (H₂O₂) is undoubtedly a more efficient solar energy conversion strategy with high atom economy. Herein, we have developed an efficient photocatalyst of bismuth-molybdate (Bi₂MoO₆) hierarchical hollow microspheres with tunable surface oxygen vacancies (OVs) for promoting the photocatalytic selective alcohol oxidation with H₂O₂ production. The effect of surface OVs on the photocatalytic efficiency is studied systematically by comparing the performance of different photocatalysts. The benzaldehyde and H₂O₂ production rates over the OV-rich Bi₂MoO₆ photocatalyst reach up to 1310 and 67.2 μmol g⁻¹ h⁻¹, respectively, which are 2.3 and 4.0 times those generated from the OV-poor Bi₂MoO₆ hollow microspheres. The roles of various active radicals in the photocatalytic reaction are probed by a series of controlled experiments and in situ ESR measurements, revealing that both superoxide radical (•${\mathrm{O}}_2^{-}$) and carbon-centered radical are the key active intermediates. The introduction of surface OVs on Bi₂MoO₆ hollow microspheres accelerates the separation and transfer of photo-generated charge carriers as well as enhances the adsorption and activation of reactant molecules, thereby greatly promoting the photocatalytic selective oxidation of alcohols along with H₂O₂ production. This work not only demonstrates a facile strategy for the preparation of high-efficiency photocatalysts by simultaneous modulations of morphology and surface defects, but also offers insight into developing the dual-functional photocatalytic reactions for the full utilizations of photoinduced electrons and holes.

将醇光催化选择性氧化成高附加值的羰基化合物并伴随产生过氧化氢（H ₂ O ₂）无疑是一种具有高原子经济性的更有效的太阳能转化策略。本文中，我们开发了一种高效的铋酸钼（Bi ₂ MoO ₆）分级中空微球光催化剂，该光微球具有可调的表面氧空位（OVs），可促进H ₂ O ₂产生的光催化选择性醇氧化。通过比较不同光催化剂的性能，系统地研究了表面OVs对光催化效率的影响。苯甲醛和H ₂ O ₂富含OV的Bi ₂ MoO ₆光催化剂的生产率分别达到1310和67.2μmolg ^-1 h ^-1，分别是由贫OV的Bi ₂ MoO ₆中空微球产生的产率的2.3和4.0倍。通过一系列受控实验和原位ESR测量，探索了各种活性自由基在光催化反应中的作用，揭示了两个超氧化物自由基（•${\mathrm{Ø}}_{\mathrm{2个}}^{--}$）和以碳为中心的自由基是关键的活性中间体。在Bi ₂ MoO ₆空心微球上引入表面OVs加速了光生电荷载体的分离和转移，并增强了反应物分子的吸附和活化，从而大大促进了醇与H ₂ O ₂的光催化选择性氧化。生产。这项工作不仅展示了通过同时调节形态和表面缺陷来制备高效光催化剂的简便策略，而且还为开发可充分利用光致电子和空穴的双功能光催化反应提供了见识。