Photocatalytic activity of pulse electrodeposited CuAlSe2 films

Nanocrystalline CuAlSe2 (CAS) films were prepared on fin oxide coated glass substrates (5 ohms/sq) by the pulse electrochemical method at different current densities of 15 mA cm(-2), 30 mA cm(-2) and 40 mA cm(-2) and at a constant ON time of 100 ms and OFF time of 100 ms. X-ray diffraction studies indicated the formation of nanocrystallites with size in the range of 6 nm - 12 nm. Single phase CuAlSe2 chalcopyrite structure was observed in all the films. The peak width increased with deposition current density. Transmission electron micrographs exhibited uniform distribution of the particles with spherical shape. The band gap values of 2.76 eV, 2.82 eV, 2.85 eV for the films deposited at 50 mA cm(-2), 35 mA cm(-2) and 15 mA cm(-2) respectively from Tauc's plot. Photocatalytic degradation of Rhodamine B dye was studied using visible light. Dye was completely degraded after passage of 90 min. The photocatalytic process followed the first order kinetic model of Langmuir Hinshelwood.