Green synthesis of Au–Ag alloy nanoparticles using Lysimachia christinae polysaccharide and its application for reducing CO in cigarette mainstream smoke

An environmentally friendly and facile method for the synthesis of small-sized Au–Ag alloy nanoparticles is proposed. The method involves the coreduction of HAuCl 4 and AgNO 3 using Lysimachia christinae polysaccharide as reductant and stabiliser at 85°C. The synthesised alloy nanoparticles with a mean diameter of 3.81 nm are stable in solution due to the stabilising effect of the polysaccharide. Furthermore, Au–Ag nanoparticles have first been introduced into cigarette filter to serve as a synergistic catalyst for reducing CO in mainstream smoke.