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 CO 2 with epoxides is critical for atom-economical synthesis of cyclic carbonates yet remains a formidable challenge. In this work, a WO 3 –MoO 3 heterostructure is constructed for the solvent-free coupling of CO 2 with styrene oxide (SO). This design can induce collaborative effects via interfacial electron transfer between WO 3 and MoO 3, 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 WO 3 (30.1 kJ mol –1 ) and MoO 3 (30.8 kJ mol –1 ). The WO 3 –MoO 3 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 CO 2 fixation catalysts.