A novel Co, O co-doped Ag2S bimetallic oxysulfide catalyst for efficiently catalytic reduction of 4-nitrophenol and organic dyes

Monoclinic argentite Ag2S-based AgCoOS oxysulfide catalyst with high catalytic reduction performance in the dark with NaBH4 was prepared via a facial method. The co-doping of transition metal cations and anions was employed to effectively adjust the electron transfer property of the catalyst, with O used to modify the energy band structure and Co to provide extra active sites for the electrophilic and nucleophile reactions. The hybridization of O and S orbitals promoted the stability of the Ag2S-based catalyst. The optimized doping amount of 2.40% led to the highest catalytic reduction performance, as demonstrated by AgCoOS-3 catalyst, which achieved a complete reduction of 4-NP, MB, MO, and RhB (100 ml, 50 ppm) within 10 min, 6 min, 8 min, and 6 min, respectively, while maintaining good stability during the cycling tests. The response surface and contour plots were adopted to provide insights into the interactions between variables and their impact on the catalytic reduction reaction performance. The results suggest that the high-performance Co, O co-doped Ag2S catalyst synthesized by the green procedures has excellent potential for industrial wastewater treatment applications. & COPY; 2023 Vietnam National University, Hanoi. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).