Solar cells prototypes combining electrodeposited ZnO and CuInS2

MARIANA BERRUET; YESICA DI IORIO; MARCELA VAZQUEZ

Joao Pessoa

Encuentro; XIII Brazilian MRS Meeting; 2014

SBPMat

This work aims at obtaining a solar cell prototype using exclusively electrodeposition to buid up the n-p junction. This method is cost-effective, does not require high vacuum, is suitable for a wide variety substrates and can be scaled to industrial production. ZnO and CuInS2 (CIS) are subsequently electrodeposited on tin oxide glass substrates (TCO). These act as n-type and p-type semiconductors, respectively, in a solar cell with superstrate configuration. A conventional electrochemical cell with three electrodes was employed. Depositions were performed at fixed potential. ZnO nanotubes were deposited from a Zn(NO3)2 precursor solution. CIS deposition was carried out at pH > 5 to protect the ZnO layer. Then the films were annealed in a sulfur atmosphere and finally etched in KCN to remove detrimental binary phases. The morphology, thickness, crystalline structure and composition of electrodeposited ZnO, CIS and FTO/ZnO/CIS were analyzed by SEM, XRD, Raman spectroscopy and EDX/XPS, respectively. The energy gap (Eg) was evaluated from UV -Vis spectra. Voltage-current curves were performed in the dark and under illumination with a solar simulator to analyze the response and efficiency of the prototype of solar cell. The synthesis parameters were adjusted to maximize the efficiency of the solar cell.