Diamond-Like Carbon Film Deposited via Electrochemical Route for Antireflection Applications in Photovoltaic

Abstract

Diamond-like carbon (DLC) is widely studied for various applications such as optoelectronics, energy, aerospace, and medicine. It’s hard, chemically inert, and optically transparent. Due to its superior antireflection properties, DLC films are more suited for photovoltaic technology. Here in this work, we report a facile, high speed, and low-cost method of DLC film development from an aqueous solution via electrodeposition. The effect of applied voltage and solution concentration on the properties of DLC film was analyzed. The morphology, shape, and uniformity of the DLCs were analyzed with optical and electron microscopies. The presence of C-H, C-C, and C=C bonds in the DLC films was confirmed from FTIR and Raman spectroscopies. Whereas the optical behavior was analyzed with a UV-Vis-NIR spectrophotometer. The DLC films were deposited at 2.7 V, 4V, 6V, 8V, and 10V, and it was shown that for a fixed electrolyte concentration and electrode spacing, the applied voltage can be adjusted to obtain varying deposition rates. Likewise, the solution concentration was varied in the 2 vol.% to 10 vol.%, and it was demonstrated that by increasing the solution concentration the deposition rate increases. The increase in the deposition rate was evidenced by an increase in the deposition current as well as the roughness of the films. It was noticed that smaller-sized, well-defined, and more uniform DLC films were obtained at lower concentrations and low voltage levels. The band gap was varied between 2.91ev to 3.39ev. It was clearly shown that reflection reduced remarkably after depositing DLC film on the substrate surface. This work demonstrates that DLC film has a potential to utilized as an antireflection layer in photovoltaic application.