CeO₂/3D g-C₃N₄ heterojunction deposited with Pt cocatalyst for enhanced photocatalytic CO₂ reduction

The conversion of CO₂ into high value-added carbon-based compounds through photocatalytic reduction technology is considered as one of the more promising strategies to solve the greenhouse effect. And construction of heterojunction photocatalysts can promote the separation of photoelectron-hole pairs, so as to achieve higher activity of photocatalytic CO₂ reduction. Hence, Pt@CeO₂/3DCN heterojunction are prepared by calcination method and photoreduction technology. The photocatalytic results revealed that Pt@CeO₂/3DCN show better photocatalytic activity for reducing CO₂ into CO and CH₄, compared with 3DCN. Especially, Pt@45CeO₂/3DCN shows the maximum photocatalytic activity of 4.69 and 3.03 μmol·h⁻¹·g⁻¹ for CO and CH₄ under UV light irradiation, respectively, and the reduction activity did not decrease significantly after five cycles. The enhanced photoreduction of CO₂ performance can be ascribed to the synergistic effects of the oxygen vacancies in CeO₂ for CO₂ activation and heterojunction for electron separation. Besides, Pt nanoparticles (NPs) on CeO₂/3DCN can further promote the transfer of electrons, resulting in higher photocatalytic activity.