Study on the preparation of ultrafine copper powder by glycerol solvothermal method

In order to investigate the effect of the alcohol solvothermal method on the properties of the prepared ultrafine copper powders, an experimental study was conducted under alkaline conditions using glycerol as both the solvent and reducing agent, without the addition of any stabilizer or dispersant. By systematically examining the effects of various reaction parameters on the copper powders, the reaction mechanism and particle formation mechanism were elucidated, and the antioxidant properties of the resulting products were investigated. The results show that NaOH can enhance the reduction of alcohol molecules, thereby accelerating the reaction rate. Meanwhile, it can promote the dissolution of the intermediate Cu₂O, which regulates the concentration of copper ions and the particle size of copper powder morphology. The modifying effect of anions in the copper source on the crystal surface is an important factor influencing the morphology of copper powders. Spherical copper powders with an average particle size of 230 nm were produced by using Cu(NO₃)₂ as a copper source at 150 ℃ with an alkali-copper ratio of 3∶1. The product exhibits good thermal stability and oxidation resistance, with an initial oxidation temperature of about 180 °C and the ability to remain unoxidized in air for at least 30 d.