Monodispersed Mesoporous Silica Spheres Supported Co3O4 as Robust Catalyst for Oxygen Evolution Reaction

Monodispersed mesoporous silica spheres (MSS) with fibrous nanostructure and highly-open porosity were fabricated by a facile one-pot synthetic route and loaded with Co3O4 nanoclusters for catalyzing the oxygen evolution reaction with Ru(bpy)32+-S2O82- photosensitizer and sacrificial reagent system. The effect of loading amount on the morphology and microstructure of Co3O4 was investigated and it was found that lower Co3O4 content in the composite materials results in smaller crystallite size, which in turn leads to significantly enhanced oxygen evolution activity. Furthermore, due to the monodispersity of the spheres and good accessibility of active species offered by the fibrous pore structure the material shows a clear advantage over non-supported Co3O4 nanoparticles and commonly used ordered mesoporous silica supports such as KIT-6 and SBA-15.