Universal Synthesis of Core–Shell‐Structured Ordered Mesoporous Transition Metal Dichalcogenides/Metal Oxides Heterostructures with Active Edge Sites

Abstract

Two‐dimensional (2D) transition metal dichalcogenides (TMDs) are widely used in interfacial reactions and electronic devices due to their tunable bandgap and high efficiency of carrier transport. However, the lack of fully exposed active sites in bulk samples or stacked nanosheets leads to limited performances. In this work, a general method is developed to construct ordered mesoporous TMDs/metal oxides (OM‐TMDs/MOs) heterostructures, including WS2/WO3, WSe2/WO3, WTe2/WO3, MoS2/MoO3, and V3S4/V2O3, through one‐step thermal sulfurization (selenidation/tellurization) of self‐assembled amphiphilic block copolymer/polyoxometalates clusters nanocomposites with ordered mesostructures. The OM‐TMDs/MOs possess highly OM structures with high specific surface area, large pore size, and rich active edge sites in the frameworks of heterostructures. The chemiresistive gas sensor based on OM‐WS2/WO3 shows excellent NO2‐sensing performances at room temperature, with high sensitivity, ultrahigh selectivity (/Sgas > 20), and fast response speed (6 s). Theoretical study reveals that the strong adsorption capacity of WS2/WO3 heterostructure and edge sites of WS2 for NO2 molecules and the high charge transfer between them contribute to high selectivity and sensitivity of the sensor. This universal method provides novel strategy for synthesis of OM TMDs‐based nanomaterials, showing great potential in various applications such as electronic devices, catalysis, energy storage, and conversions.