2D WC/WO₃ heterogeneous hybrid for photocatalytic decomposition of organic compounds with vis–NIR light

Abstract

Developing catalysts to improve charge-carrier transfer and separation is critical for efficient photocatalytic applications driven by low-energy photons. van der Waals stacking of 2D materials has opened up opportunities to engineer heteromaterials for strong interlayer excitonic transition. However, fabrication of 2D heteromaterials with clean and seamless interfaces remains challenging. Here, a 2D tungsten carbide/tungsten trioxide (WC/WO₃) heterogeneous hybrid in situ synthesized by a chemical engineering method has been reported. The hybrid comprises of layer-by-layer stacked WC and WO₃ monolayers. The WC and specific interfacial interfaces between the WC and WO₃ layers exhibit synergetic effects, promoting interfacial charge transfer and separation. Binderless WC performing platinum-like behavior works as a potential substitute for noble metals and accelerates multielectron oxygen reduction, consequently speeding up the photocatalytic decomposition of organic compounds over the WO₃ catalyst. The specific interfacial interaction between WC and WO₃ layers potentially improves interfacial charge transfer from conduction band of WO₃ to WC. In the absence of noble metals, the WC/WO₃ hybrid as a catalyst exhibits distinct decomposition of organic compounds with vis–NIR light (λ = 400–800 nm). This finding provides a cost-effective approach to capture low-energy photons in environmental remediation applications.