Worm-like InP/TiO2 NTs heterojunction with unmatched energy band photo-enhanced electrocatalytic reduction of CO2 to methanol

• WL-InP/TiO2 NTs was obtained by hydrothermal method.
• The individual photocatalysis could not realize for the positive CB.
• The target catalyst realized the photo-enhanced electrocatalytic reduction of CO2 to methanol.

In this paper, the worm-like (WL) InP/TiO2 NTs heterojunction with unmatched energy band was obtained by hydrothermal method to modify worm like InP on TiO2 NTs. The SEM result showed that the worm like InP was densely packed on the TiO2 NTs substrate. After InP modification, the visible light absorption was enhanced greatly and the band gap was narrowed from 3.20 eV to 1.52 eV. The conduction band and valence band of WL-InP/TiO2 NTs located at −0.28 eV and 1.24 eV, respectively. The individual photocatalysis did not have enough reduction ability for the unmatched energy band, so photo-enhanced electrocatalytic reduction was selected to convert CO2. The major product was methanol, and the methanol concentration of photo-enhanced electrocatalysis and electrocatalysis after 5 h was 5.89 and 3.85 mmol L−1, respectively. It showed that the electrocatalytic reduction of CO2 increased to 1.53 times by introducing visible light irradiation.