Copper oxide based nanostructures for improved solar cell efficiency

Resurgence of copper oxide based thin film solar cells demands exclusive methods of integrating various layers with superior constituents for increased solar-electric conversion efficiency. Exceedingly optically active nanostructured phase mixture of copper oxides was synthesized by an energy efficient hydrothermal process. Comprehensive structural and optical studies of these nanostructured copper oxides reveal its efficacy as a unique solar cell material. Excellent solar cell characteristics have been observed when these nanopowders are integrated with ZnO/CuO based thin films. X-ray diffraction, Raman micro-scattering, scanning electronmicroscopy, energy dispersive X-ray spectroscopy, UV-vis spectroscopy, atomic force microscopy, and optoelectronic measurements were employed to characterize these unified electronic devices. Solar cell measurements indicate a considerable increase in short circuit current density (J(sc)) and open circuit voltage (V-oc) in the fabricated nanostructure powder-thin film hybrid solar cell devices. The solar cell efficiency of these nanopowder-thin film devices is found to be 2.88%. The physics behind this enrichment of solar cell properties has also been elucidated in the study. Exhaustive Raman spectroscopic and photoluminescence studies prove that multi-phonon scattering may play a major role for this enhancement. This integration of nanostructures with thin film solar cells can evolve to a new direction in photovoltaic technology. (C) 2014 Elsevier B.V. All rights reserved.