Controllable synthesis of CuPc/N-rich doped (0 0 1) TiO2 S-scheme nanosheet heterojunctions for efficiently wide-visible light-driven CO2 reduction

•N-rich doped (001) TiO2 is prepared by the high-temperature nitridation to phosphate-modified one.•A wide-visible-light responsive S-scheme heterojunction of CuPc/N-rich doped (001) TiO2 is constructed.•As-fabricated heterojunctions exhibit high visible-light catalytic activities for CO2 conversion.•Abundant OH groups accompanied by the high-amount N doping make heterojunction interface close.•Used CuPc as reductive-constituent brings isolated Cu-N4 sites for preferable CO2 activation.