Analytical study to determine the optical properties of gold nanoparticles in the visible solar spectrum

In this work the optical properties of the formed gold nanoparticles, that obtained upon reducing the gold(I):6-thioguanosine hydrogel by dimethylamine borane (DMAB) have been studied. The analytical measurements to calculate the optical band gap showed a significant narrowing in the optical band gap value (E(g)). Tauc plot was used to estimate the optical band gap (Eg) with the direct and indirect allowed transitions, before and after the reducing process. Narrowing the band gap is very important to increase the efficiency of the semiconductor material as it leads to absorbing in the visible region of the solar spectrum.