Self-driven in situ facile synthesis of CuO/Cu2O for enhanced catalytic reduction of 4-nitrophenol by acetic acid

Abstract

A series of CuO, Cu₂O and CuO/Cu₂O catalyst structures with different morphologies are synthesized in situ by controlling the anionic species of the copper salts in the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). The prepared CuO/Cu₂O-r_Ac is used to catalytically reduce 4-NP. It shows that CuO/Cu₂O-r_Ac prepared using Cu(Ac)₂·H₂O as the copper source exhibits a higher k of 0.2019 min⁻¹ and a k_m of 0.2019 min⁻¹ μg⁻¹. The catalytic reduction property is in accordance with the CH₃COOH content of CuO/Cu₂O-r_Ac. The obtained CuO and Cu₂O can form a heterojunction structure, improving the electron-transfer rate for enhancing the adsorption of 4-NP and the desorption of 4-AP. Moreover, a key factor that affects the catalytic efficiency of CuO/Cu₂O-r_Ac is the pH, which affects NaBH₄ to form H₂. This production strategy is highly efficient and can be used to fabricate other similar catalytic hydrogenation reactions.