A green and facile synthesis route of nanosize cupric oxide at room temperature

Heat, ultrasonic, microwave, and external energy are the essential conditions in the conventional preparation of nano-cupric oxide (CuO) from copper hydroxide (Cu(OH)2) precursor. In this work, CuSO4 aqueous solution (0.02 mol) was gradually added dropwise into the methanol/sodium hydroxide (NaOH/CH3OH) solution (0.04 mol) in 20 min at normal temperature and then constantly stirred the black solution for about 5 min; nano-CuO was synthesized. The as-prepared CuO had a high purity and a regular nanosize of 4–10 nm. What is more, the by-product sodium sulfate (Na2SO4) could be separated using a high-speed centrifuge, indicating that the methanol could be conveniently recycled; thereby, an environmentally friendly sustainable route of the preparation of nano-CuO was developed. In addition, the as-prepared nano-CuO was melt-compounded with polyamide 6 to produce fiber composites. The results showed that the nano-CuO was uniformly dispersed in PA6 fiber composites and presented an excellent antibacterial performance. Most importantly, the function of methanol in the dehydration process was revealed.