Highly Dispersive Cobalt Oxide Constructed in Confined Space for Oxygen Evolution Reaction

Cobalt-based catalysts are highly promising for the oxygen evolution reaction (OER) in terms of both cost and performance. The dispersion state of Co3O4 impacts the catalyst performances directly, while development of an efficient method for Co3O4 dispersion remains a pronounced challenge. In this study, it is the first time that the confined space strategy (CSS) is employed to make highly dispersive Co3O4 on the mesoporous silica (MS) SBA-15. The precursor of Co3O4 is successfully introduced into the confined space inherent in as-prepared SBA-15 (between the silica walls and the template). The CSS facilitates the formation of Co3O4 with extremely high dispersion after the decomposition of Co precursor. Up to 4 mmol of Co3O4 can be dispersed in per gram of MS without any X-ray diffraction lines (the obtained sample is denoted as 4CoAS), while obvious diffraction lines are detected in the counterpart prepared from calcined SBA-15 (the sample is denoted as 4CoCS). Further calculation indicates that the size...