Plasma induced liquid-phase synthesis of Ce/Mo metal oxides as photocatalysts

Highlights: • Ce₂Mo₃O_x were firstly prepared with plasma induced-liquid phase method. • The degradation rate of 1000 mL (50 mg/L) MO could reach 98% within 6 min. • The degradation of MO was mainly driven by the participation of O₂⁻ and OH. Ce/Mo metal oxides were synthesized by plasma induced liquid-phase method and applied for photocatalysis. Compared with the traditional co-precipitation method and hydrothermal method, the Ce/Mo metal oxides prepared with plasma-assisted method had excellent UV-light photocatalytic properties. Ce/Mo metal oxides synthesized with plasma possessed regular micromorphology, good crystallinity, as well as oxygen vacancy, which were beneficial to photocatalytic performance. Compared with the photocatalytic activity of CeO₂ and MoO₂ alone, the photocatalytic activity enhancement of the Ce/Mo metal oxides could be ascribed to the efficient separation of the photogenerated electron-hole pairs. The degradation rate of 1000 mL (50 mg/L) methyl orange (MO) could reach 98% within 6 min under UV-light radiation. The reaction mechanism of the photocatalytic reaction process was deduced mainly as the coordinated oxidation process of superoxide radicals(O₂⁻) and hydroxyl radicals(OH). The reusability experiments proved that Ce/Mo metal oxides exhibited prominent stability and repeatability. Ce/Mo metal oxides exhibited excellent photocatalytic performance for different dyes, and had potential application prospect in dye wastewater treatment.