Collaborative Interface Engineering of the WO ₃ –MoO ₃ Heterostructure Enabling Accelerated CO ₂ Cycloaddition with Epoxides

The construction of heterogeneous catalysts for the solvent-free cycloaddition of CO₂ with epoxides is critical for atom-economical synthesis of cyclic carbonates yet remains a formidable challenge. In this work, a WO₃-MoO₃ heterostructure is constructed for the solvent-free coupling of CO₂ with styrene oxide (SO). This design can induce collaborative effects via interfacial electron transfer between WO₃ and MoO₃, thereby facilitating charge redistribution and creating unique electronic configurations. As a result, the cycloaddition kinetics are significantly enhanced, as reflected by a markedly lower apparent activation energy (17.6 kJ mol⁻¹) than those of pristine WO₃ (30.1 kJ mol⁻¹) and MoO₃ (30.8 kJ mol⁻¹). The WO₃-MoO₃ catalyst achieves a high styrene carbonate (SC) yield of 93.7%, with a normalized reaction rate of 2.9 × 10⁻² mol m⁻² h⁻¹ under solvent-free conditions, and demonstrates good cycling stability. This study highlights the effectiveness of heterostructure engineering in tailoring active sites and electronic properties, offering a promising strategy for developing high-performance CO₂ fixation catalysts.