Construction and photocatalytic performance of delafossite-type CuAlO2/CuGaO2 heterostructure

The study aimed to synthesize and characterize a delafossite-type CuAlO2/CuGaO2 heterostructure and assess its photocatalytic performance. CuAlO2 particle was synthesized through a high-temperature solid-state reaction and subsequently combined with a CuGaO2 precursor solution via hydrothermal processing, resulting in the formation of a Type-II CuAlO2/CuGaO2 heterostructure. Electrochemical analysis revealed the superior performance of the heterostructure compared to individual CuAlO2 and CuGaO2 photocatalysts. The heterostructure exhibited increased carrier concentration, enhanced redox capabilities, superior electrochemical stability, and reduced interfacial resistance. Photocatalytic experiments, focusing on tetracycline hydrochloride degradation, demonstrated the remarkable oxidation potential of the CuAlO2/CuGaO2 heterostructure, outperforming CuAlO2 and CuGaO2 degradation rates by factors of 2.38 and 2.82, respectively. This outstanding performance can be attributed to the unique architecture of the heterostructure, facilitating the selective migration of photogenerated electrons and holes to the appropriate energy levels of the constituent materials, thereby enhancing charge carrier separation efficiency. Furthermore, investigations into photocatalytic water splitting highlighted the notable reduction activity of the CuAlO2/CuGaO2 heterostructure, resulting in hydrogen production rates exceeding those of CuAlO2 and CuGaO2 by factors of 1.12 and 2.84, respectively. These findings underscore the superior performance of the CuAlO2/CuGaO2 heterostructure across various photocatalytic reactions, emphasizing its broad applicability.