Microfluidic assembly of WO ₃ /MoS ₂ Z‐scheme heterojunction as tandem photocatalyst for nitrobenzene hydrogenation

Abstract

Abstract Heterojunction‐based photocatalyst plays an important role in the various heterogeneous catalyses. Z‐scheme photocatalytic systems with two semiconductor materials are suitable for harvesting solar energy, while the advanced nanostructuring tools for the fabrication of Z‐scheme heterojunction are limited. Here, WO 3 /MoS 2 (W/M 0.2 ) heterojunction composites were constructed in a microfluidic system with enhanced assembly efficiency, and the photocatalytic performance has been investigated using X‐ray photoelectron spectroscopy (XPS), Mott–Schottky (M–S) analysis and gas chromatograph‐mass spectrometer (GC–MS). In addition, in the reduction of nitrobenzene, the photogenerated hole (h + ) oxidation of formic acid (HCOOH) provides the hydrogen source and the deposited Pd nanoparticles are enriched with photogenerated electrons for improving the transfer hydrogenation efficiency. The microfluidic‐prepared tandem photocatalyst gives a meaningful guidance for the design and synthesis of heterojunction catalysts, which is promising for energy maximizing control systems.