INFLUENCE OF NANOCELLULOSE CONCENTRATION ON OPTOELECTRONIC PROPERTIES OF ELECTROPLATED CADMIUM TELLURIDE THIN FILMS

Abstract

Cadmium telluride (CdTe) doped nanocellulose thin films were successfully deposited on glass/fluorine doped tin-oxide (FTO) substrates from an aqueous electrolyte bath containing hydrated Cadmium sulphate (CdTe.8H2O) and tellurium dioxide (TeO2) using electrodeposition technique (ED). Six samples of Cadmium telluride (CdTe) thin films were grown with nanocellulose concentration of 0, 1, 3, 5, 7 and 9 ppm. Electronic data of the deposited layers using photo electrochemical (PEC) cell measurement agrees favourably with theoretical formulation. The results obtained from (UV-Vis) spectrophotometer showed that the bandgap of the films ranges between 1.32 and 1.67 eV, an open circuit voltage of 1400mV, average deposition current (𝐼𝑎𝑣) and deposition current density (𝐽𝑆𝐶) of 1.247mA and 0.182mA cm-2 respectively. Lowest energy bandgap of CdTe(1.32 eV) was achieved at a concentration of 9ppm. This is novel in recent study of the guest of researchers to obtain low bandgap formation of CdTe thin films. Photoelectrochemical (PEC) cell measurement revealed that the electrical conductivity type of undoped CdTe as n-type while the doped CdTe was p-type. Hence, it is possible to effectively tune the conductive properties of CdTe by careful addition of nanocellulose concentration