Photo-splitting of water toward hydrogen production and active oxygen species for methane activation to methanol on Co-SrTiO3

Abstract

Direct activation of the C-H bond of CH4 under moderate conditions is highly desired but a great challenge. This work proposes a strategy for activation of the C-H bond in CH4 via the active O species generated from photo-splitting of H2O, simultaneously generating value-added CH3OH and H2. This has been achieved on SrTiO3-supported Co particles with abundant Co-SrTiO3 interfacial sites in which H2O is photo-oxidized on SrTiO3 to H2O2, which then decomposes to the active OH radical to attack the activated CH4 on the Co particle. As a result, 1.84 mmol h−1 on per gram of Co (mmol gCo−1 h−1) of CH3OH with an extraordinary selectivity of 98.7% was obtained, and the efficiency of H2 production improved to 2.4 times higher than that from overall photocatalytic H2O splitting.