TY - JOUR AU - Liu, Bingbing AU - Li, Jin AU - Shu, Zhaoqin AU - Zhong, Lian PY - 2026 TI - Synthesis of Gold-Silver Bimetallic Nanoparticles and Catalytic Reduction of 4-Nitrophenol JO - Periodical of Ocean University of China SN - 1672-5174 SP - 49 EP - 59 VL - 56 IS - 4 AB - Gold-silver bimetallic nanoparticles (Au-Ag NPs) were successfully synthesized by simultaneous reduction of HAuCl4 and AgNO3 using water-soluble chitosan (WSC) as the reducing agent and stabilizer. The effects of the volume ratio of gold and silver precursors(V(HAuCl4)/V(AgNO3)), reaction temperature and time, NaOH and WSC concentration were investigated. The Au-Ag NPs were characterized by ultraviolet-visible absorption spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS). The catalytic reduction performance of Au-Ag NPs towards 4-nitrophenol (4-NP) was investigated. The results showed that spherical or nearly spherical Au-Ag NPs with an average particle size of 4 nm were prepared using WSC as the reducing agent and stabilizer. The catalytic reduction activity of Au-Ag NPs towards 4-NP was better than that of AuNPs and AgNPs, and the highest catalytic activity was obtained for Au0.5Ag0.5(V(HAuCl4)/V(AgNO3)=1∶1). When Au0.5Ag0.5 was used as catalyst, the conversion of 4-NP could reach 99.1% when the catalytic reaction was carried out at 30 ℃for 30 min, the reaction rate constant was 0.190 3 min-1, and the reaction activation energy Ea was 31.1 kJ·mol-1. UR - https://doi.org/10.16441/j.cnki.hdxb.20250102 DO - 10.16441/j.cnki.hdxb.20250102