A Mesoporous CuO/CuSe Heterojunction Nanocomposite with Applications in Visible‐Light Photocatalysis and as an Electrochemical Phenol Sensor

Abstract A new study has successfully fabricated a CuO/CuSe heterojunction nanocomposite using an eco‐friendly green method, which can be used as a potential photocatalyst and for phenol sensing applications. The nanocomposite has been characterized using various microscopic and spectroscopic methods, and it was found to have a direct band gap value of 2.14 eV, which indicates it can exploit visible light for its properties. The nanocomposite was tested for photocatalytic degradation of two dyes, Rhodamine B (RhB) and Methyl Orange (MO), and achieved removal efficiencies of 99.32 % and 88.20 %, respectively, using hydrogen peroxide. The nanocomposite was also found to have potentiality for practical use in phenol sensing, detecting concentrations of 0.2–1.4 μM phenol in solution and demonstrating 96–100 % phenol recovery in real water samples.