Enhanced photabsorption and supercapacitive potentials of MnS thin film electrode with Li-ions incorporation for optoelectronic and energy storage applications

Abstract

MnS and lithium-doped MnS thin films were prepared on Indium Tin Oxide (ITO) conductive substrates from appropriate inorganic chemical reagents using two-electrode electrochemical deposition technique. Effects of Li-ions incorporation as dopant impurity on some surface properties of the thin film: optical, electrical and electrochemical cyclic voltammetry responses, were investigated to explore the films’ optoelectronic and energy storage potentials. The optical result showed high absorbance in the UV region and high transmittance towards visible and infrared spectra wavelength range of EM spectrum. Direct allowed transition with decreasing energy band gap value from 2.03 eV to 1.85 eV relative to lithium dopant concentration was observed. The film also revealed increasing surface conductivity with thickness. Enhanced electrochemical charge storage of the MnS host material leading to specific capacitance value of 95 F g-1 was also instigated by the Li+ ions incorporation. The study demonstrated that MnS and lithium-doped MnS thin films are suitable electrode materials for energy harvesting and electrochemical energy storage devices.