Method for synthesizing colloidal gold nanoparticles under atmospheric air plasma liquid phase

The invention discloses a method for synthesizing colloidal gold nanoparticles under an atmospheric air plasma liquid phase. Mixed solution of chloroauric acid and a reducing agent is put in a container with an insulation material; and then, atmospheric air plasma is filled in the mixed solution to prepare the colloidal gold nanoparticles. The method adopts an atmospheric air plasma reducing mode, and has such characteristics as low temperature, normal pressure, low energy consumption, fast decomposition process and environmental protection; the obtained metal nanoparticles are uniform in particle size, and can stably suspend in water solution; and more electrons are wrapped on the surfaces of the nanoparticles, so that the Zeta potential and the detecting sensitivity are higher.