Sonochemical decomposition of noble metal oxides and sonochemical alloying of gold–silver systems

Recently, environmental problems, such as global warming, have become more severe; thus, there is a requirement to implement sustainable development goals in materials processing. In this study, we investigated a low-cost and environmentally-friendly sonochemical process for the synthesis of metal nanoparticles with large specific surface areas and catalysis effects. Au(2)O(3) hydrate and Ag(2)O were reduced to Au and Ag, respectively, at room temperature in a short time when irradiated with ultrasound in ethanol. Furthermore, when a mixed powder of Au(2)O(3) hydrate and Ag(2)O was irradiated in ethanol, Au–Ag alloys were obtained in only 10 min. This fast and environmentally friendly alloying technique, known as sonochemical alloying, is promising for alloy syntheses.