Development of Potential Pulse Deposition (PPD) of CdTe and its application on Au nanorods

CdTe is a promising  photovoltaic absorber material for efficient solar energy conversion due to its ideal band gap (~1.5 eV). Thin films of Cadmium telluride (CdTe) were electrodeposited onto Au substrates from an acidic aqueous solution of CdSO4, and TeO2 using a flow cell at room temperature. The deposition potential and solution flow were controlled and optimized during the deposition. Compared with traditional codeposition1 and electrochemical atomic layer deposition (E-ALD) methods 2, the potential pulse deposition offers a new method  to produce higher quality films much faster. Parametric variables for controlling the Cd/Te ratio and morphology were also established.

Incorporation semiconductors has seen a surge of interest with the ever-increasing development of nanotechnology3, including thin films, nanosheets, nanotubes and nanorods.4 By incorporating these nanostructures, higher solar conversion efficiency can be achieved using much less material. In this talk, results of ultra-thin CdTe film deposited on Au nanorods will be presented. In accordance with the expectations, the film made using potential pulse method showed more stable and consistent stoichiometric results of CdTe on Au nanorods electrode than traditional co-deposition. With further optimization of CdTe/Au nanorods, better photoresponse can be expected due to the plasmon effect from the Au nanostructure and increased surface area.

1. Panicker, M. P. R.; Knaster, M.; Kroger, F. A., Cathodic Deposition of CdTe from Aqueous Electrolytes. J. Electrochem. Soc. 1978, 125 (4), 566-572.
2. Banga, D.; Perdue, B.; Stickney, J., Electrodeposition of a PbTe/CdTe superlattice by electrochemical atomic layer deposition (E-ALD). J Electroanal Chem 2014, 716 (Supplement C), 129-135.
3. Ali, N.; Hussain, A.; Ahmed, R.; Wang, M. K.; Zhao, C.; Haq, B. U.; Fu, Y. Q., Advances in nanostructured thin film materials for solar cell applications. Renewable and Sustainable Energy Reviews 2016, 59 (Supplement C), 726-737.
4. Liyanage, W. P. R.; Wilson, J. S.; Kinzel, E. C.; Durant, B. K.; Nath, M., Fabrication of CdTe nanorod arrays over large area through patterned electrodeposition for efficient solar energy conversion. Solar Energy Materials and Solar Cells 2015, 133, 260-267.