Mechanism for the photoreduction of poly(vinylpyrrolidone) to HAuCl4 and the dominating saturable absorption of Au colloids.

Both fabrication of Au nano-objects and the nonlinear optical properties of Au nano-objects are the focus of research. In the present work, Au nanoparticles with different mean sizes (18, 32, 42, and 70 nm) are controllably fabricated in ethanol by changing the concentration of poly(vinylpyrrolidone) (PVP) and HAuCl4, as well as the power of continuous wave… (More)