Structural, morphological and optical properties of pulse plated CdSe nano films

In this work, the pulse electrodeposition technique has been successfully employed for the deposition of CdSe nano-films on gold coated glass substrates. The films were deposited at a constant current density of 200 mA/cm² for a period of 10 min with duty cycles varies from 50% to 6.25%, at a bath temperature of 100°C. X-ray diffraction studies indicated hexagonal structure with peaks assigned with the earlier report. The crystallite size of the CdSe nanoparticles was estimated from the X-ray diffraction pattern by using Scherrer´s formula. Optical absorption studies indicated a direct band gap value in the range 1.70 eV-1.99 eV as the duty cycle was varied from 50% to 6.25%. The transmission electron diffraction pattern obtained on CdSe nanocrystals on (111) gold surface. At a still shorter duty cycle, for 6.25% duty cycle, the size of the particle is further reduced and nearly isolated nanocrystals are obtained.