Photoacoustic spectroscopy as a non-destructive technique for optical properties measurements of nanostructures

In this work, photoacoustic (PA) spectroscopy as a non-destructive technique has been effectively used to study the optical properties of nanostructures. Cadmium cobalt sulfide quantum dots (QDs) have been deposited onto TiO2 (Titania) electrodes using a successive ionic layer adsorption and reaction (SILAR) technique for different cycles (1 to 10). The surface morphology of the prepared photoanodes has been studied using a scanning electron microscope (SEM). The elemental properties have been investigated using an energy dispersive X-ray spectrometer. The optical properties have been measured using both PA and UV-vis. spectrophotometer. The energy band gap (E-g) of the prepared photoanodes has been tuned from 3.29 eV to 2.49 eV as the number of SILAR deposition cycles increases from 1 to 10. This increase in E-g is mainly attributed to the increase in the QDs' size and hence the quantum confinement effect.