Here we report the hydrothermal synthesis of MoS₂/Cu₂O nanocomposites with tunable heterojunction for enhancing visible light photochemical activity and stability. The conduction and valence band positions of few-layers MoS₂ have been tuned to optimize photo-induced charge separation efficiency by regulating the layer thickness of MoS₂. The photochemical activity and stability of MoS₂/Cu₂O nanoparticles are demonstrated by visible light assisted degradation of methyl orange. Among all of the samples, the MoS₂/Cu₂O nanocomposite assembled with 6000 rpm centrifuged MoS₂ has the highest degradation efficiency of 95.8 % after 3 h of visible light illumination, due to the high visible light absorption and optimized electron-hole separation by the tunable heterojunction design. The influence of MoS₂ mass ratio was further investigated. At last, for better understanding of the enhanced photochemical activity, a novel charge separation mechanism is proposed based on the band alignment and build-in electric field between Cu₂O and MoS₂.

在这里我们报告水热合成MoS ₂ / Cu ₂ O纳米复合材料与可调的异质结，以增强可见光光化学活性和稳定性。通过调整MoS ₂的层厚度，已调整了几层MoS ₂的导带和价带位置，以优化光诱导的电荷分离效率。MoS ₂ / Cu ₂ O纳米粒子的光化学活性和稳定性通过可见光辅助降解甲基橙得到了证明。在所有样品中，MoS ₂ / Cu ₂ O纳米复合材料与6000 rpm离心MoS ₂组装在一起由于可调谐异质结设计具有高可见光吸收率和优化的电子-空穴分离，在可见光照射3 h后具有最高的95.8％的降解效率。进一步研究了MoS ₂质量比的影响。最后，为了更好地理解增强的光化学活性，基于能带排列和Cu ₂ O与MoS ₂之间的内建电场，提出了一种新颖的电荷分离机理。