TiO2 phase structure strongly affects structures and photocatalytic hydrogen production of CuOx/TiO2.
Cu2O-rutile TiO2 interaction is much stronger than Cu2O-anatse TiO2 interaction.
Strong Cu2O-rutile TiO2 interaction facilitates charge transfer process but disables supported Cu2O in hole-participated methanol oxidation.
Appropriate Cu2O-anatase TiO2 interaction balances efficiencies between charge transfer process and hole-participated methanol oxidation.
Cu2O-anatase TiO2 heterojunction is much more photocatalytic active than Cu2O-rutile TiO2 heterojunction.