Photoelectrocatalytic Reduction of CO₂ to Syngas on N-Modified Self-Supporting N_y-Cu₂O/CuF Photocathode

Abstract

Photoelectrocatalytic (PEC) reduction of carbon dioxide (CO₂) with water (H₂O) into syngas not only alleviates energy and environmental crises but also provides feed gas for producing high-value chemicals. In this study, self-supported N_y-Cu₂O/CuFs are successfully prepared using copper foam as a precursor, following a self-assembly strategy to fabricate a PEC system for converting CO₂ and H₂O into syngas. N-doping facilitates the preferential growth of Cu₂O (111) crystal planes in N_y-Cu₂O/CuF, resulting in high surface oxygen vacancies. Simultaneously, appropriate surface electronic structure and good light capture capability endow the synthesized material with excellent PEC properties, achieving a syngas yield 2.5 times higher than that of the unmodified Cu_xO/CuF, with a CO yield of 58.72 μmol/(cm²·h) and the lowest H₂/CO ratio of 1.6. This study provides a promising strategy for developing high-performance photocathodes for CO₂-efficient conversion.

Keywords

Photoelectrocatalysis / Syngas / CO₂ reduction / Copper foam / Self-supporting

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