Efficient photocatalytic water splitting through titanium silicalite stabilized CoO nanodots

Water can be environmentally friendly splitted into hydrogen (H2) and hydrogen peroxide (H2O2) through photocatalysis by CoO, which is a promising strategy to alleviate energy crisis. However, the stability of CoO remains a great challenge because of the oxidation effect of the product H2O2. Herein, titanium silicalite-1 (TS-1) was employed as a framework to obtain and anchor monodisperse CoO nanodots, improve CoO photocatalytic performance, and efficiently separate the oxidizing species from CoO by adsorbing the resulting H2O2. As a result, the TS-1 prevents CoO from aggregation, surface oxidation and rapid inactivation. The CoO-TS-1 showed H2 and H2O2 production rates of 1460 μmol h−1 gCoO−1 and 1390 μmol h−1 gCoO−1 with high photostability for about 168 h. In addition, the efficiently harvested H2O2 could be directly used in the oxidation of cyclohexane into cyclohexanol and cyclohexanone with the selectivity up to 89.48%. This work paves a new way for the design of efficient and stable photocatalyst as well as the product utilization.