A two-step surface modification approach for Au and CdS NPs loaded mesoporous thin films and the greatly enhanced optical nonlinearity

A new two-step surface modification approach has been developed for the incorporation of both CdS and Au NPs into the pore channels of silica mesoporous thin films. The composite thin films were investigated by FTIR, UV-vis, XRD and SEM, the results confirmed that the semiconductor and metal NPs were successfully incorporated with uniform particle size and high dispersivity thanks to the confinement effect of mesoporous thin films. The nonlinear optical susceptibility was measured by the Z-scan technique. The synthesized multi-component nanoparticles embedded films demonstrated a greatly enhanced nonlinear optical property which can be mainly attributed to the energy transfer between CdS and Au.