The highly selective oxidation of cyclohexane to cyclohexanone and cyclohexanol (KA oil) is one of the most challenging issues in the chemical industry. However, the difficulty in attaining high selectivity and high conversion rate in parallel for the existing catalysts limits its practical application. In this paper, a novel photo-thermo synergistic catalyst was reported for the aerobic oxidation of cyclohexane. The uniform blue MoO_3-x nanowires with small diameter stabilized by polyvinyl pyrrolidone (PVP) were synthesized by a hydrothermal method, and a series of MoO_3-x-AgPd composite materials of different proportions were prepared by an in-situ reduction process. The morphology, crystalline structure, surface chemical bonding, photoelectrochemical properties of MoO_3-x-AgPd composites are thoroughly characterized. The MoO_3-x-AgPd composites present significantly increased catalytic performance than MoO_3-x nanowires in the photo-thermo synergistic catalytic oxidation of cyclohexane under dry air. The high conversion rate of 11.3% with the KA oil selectivity of 99.0% was achieved by the MoO_3-x-Ag₂₀Pd₂₀ composites under photo-thermo catalytic process at 120 ℃, which is 1.5 times of that by MoO_3-x nanowires. Under photo-thermo catalytic process, a high cyclohexane conversion rate similar to that of higher temperature thermal catalysis can be obtained at lower reaction temperature, and more cyclohexanol can be produced with a ketone to alcohol (K/A) ratio of 0.254. The significantly enhanced catalytic activity can be attributed to the effective charge transfer in the AgPd alloy nanoparticles, the optimized band gap structure, the suppressed charge recombination, and the promoted photo-thermo synergetic catalytic effect. This work provides a new reference scheme for the design and preparation of high-efficiency photo-thermo catalysts for the selective oxidation of cyclohexane.

环己烷高选择性氧化成环己酮和环己醇（KA 油）是化学工业中最具挑战性的问题之一。然而，现有催化剂难以同时获得高选择性和高转化率，限制了其实际应用。本文报道了一种用于环己烷有氧氧化的新型光热协同催化剂。采用水热法合成了聚乙烯吡咯烷酮(PVP)稳定的均匀蓝色小直径MoO _3-x纳米线，并通过原位还原工艺制备了一系列不同比例的MoO _3-x -AgPd复合材料。MoO _3-x的形貌、晶体结构、表面化学键合、光电化学性能-AgPd 复合材料被彻底表征。MoO _3-x -AgPd 复合材料在干燥空气下环己烷的光热协同催化氧化中表现出比 MoO _3-x纳米线显着提高的催化性能。用99.0％KA油选择性11.3％的高转化率是由实现的MoO _3-X -Ag ₂₀的Pd ₂₀层的复合材料的光热催化过程在120℃，这是通过的MoO的1.5倍_3-x纳米线。在光热催化过程中，可以在较低的反应温度下获得类似于高温热催化的高环己烷转化率，并且在酮醇比（K/A）为0.254的情况下可以生产更多的环己醇。显着增强的催化活性可归因于 AgPd 合金纳米粒子中的有效电荷转移、优化的带隙结构、抑制的电荷复合和促进的光热协同催化作用。该工作为设计和制备用于环己烷选择性氧化的高效光热催化剂提供了新的参考方案。