Development of cupric sulphate nanocrystals on fluorine-doped tin oxide substrates using hydrothermal technique

Abstract

Cupric sulphate nanocrystals (NCs) are desirable for a number of applications. The NCs were grown using a hydrothermal technique on Fluorine-doped Tin Oxide substrate which was sandwiched into the grooves of a sample holder at an angle between 45° and 90° relative to the wall of a 100 ml Teflon container. The surface features were observed using an optical microscope while atomic scale features which are not visible under the optical microscope were investigated using a scanning electron microscope and atomic force microscope. Details of the weight percentage composition were investigated on the sample by means of energy-dispersive X-ray spectroscopy. A broad absorption spectrum from 690 to 1100 nm, having a full width at half maximum value of 254 nm and an energy excitonic absorption peak in the visible region at 810 nm, was observed when the NCs are dissolved in water (hydrate solution) contrary to the highest absorption peak which was observed at 678 nm for the anhydrous compound. A total number of 16 vibrational frequencies were observed from Raman scattering while five active modes were visible in the Fourier Transform Infrared spectrum. Information on room-temperature photoluminescence and fluorescence spectroscopy measurements obtained from the NCs is reported. The deposition technique adopted in present work could be optimized for the high-yield production of more uniform layers of ultrathin nanostructures with increased aptitude for various applications.