Study on the preparation of ascorbic acid reduced ultrafine copper powders in the presence of different protectants and the properties of copper powders based on methionine protection

• Published in: Nanoscale advances 2024-02, Vol.6 (4), p.1135-1144
• Main Authors: Ke, Xin, Xie, Bingqing, Zhang, Jingguo, Wang, Jianwei, Li, Weiying, Ban, Liqing, Hu, Qiang, He, Huijun, Wang, Limin, Wang, Zhong
• Format: Article
• Language: English
• Subjects: Chemistry
• ISSN: 2516-0230; 2516-0230
• DOI: 10.1039/d3na01146a

High-purity, monodisperse, and low-oxygen submicron copper powder particles with particle sizes in the range of 100-600 nm were synthesized under alkaline conditions using ascorbic acid (C 6 H 8 O 6 ) as a reductant and copper chloride (CuCl 2 ·2H 2 O) as a copper source. The redox potential of the Cu-Cl-H 2 O system was obtained by calculations and plotted on pH- E diagrams, and a one-step secondary reduction process (Cu( ii ) → CuCl( i ) → Cu 2 O( i ) → Cu(0)) was proposed to slow down the reaction rate. The commonalities and differences in the nucleation and growth process of copper powders under methionine (Met), hexadecyl trimethyl ammonium bromide (CTAB), and sodium citrate dihydrate (SSC) as protectants and without the addition of protectants are compared, and the reaction mechanism is discussed. Among them, methionine (Met) showed excellent properties and the Cu 2 O( i ) → Cu(0) process was further observed by in situ XRD. The synthesized copper powder particles have higher particle size controllability, dispersibility, antioxidant properties, and stability, and can be decomposed at lower temperatures (