Novel mesoporous composites of gallia nanoparticles and silica as catalysts for the epoxidation of alkenes with hydrogen peroxide

► A new class of mesoporous composite materials containing Ga2O3 nanoparticles was synthesised. ► The gallia-silica composites containing 80 and 90% of Ga2O3 nanoparticles were identified as the most promising epoxidation catalysts in terms of activity, selectivity and reusability. ► Importance of structuring: the mesoporous composites of nanoparticles display higher catalytic activity than unstructured nanoparticles. ► The versatility of the catalysts in the epoxidation of different alkenes with hydrogen peroxide was demonstrated and the protocol for their recycling was optimised.