Single-step electrochemical deposition of Mn²⁺ doped FeS₂ thin films on ITO conducting glass substrates: physical, electrochemical and electrocatalytic properties

Mn²⁺ doped FeS₂ thin films were deposited on ITO coated conducting glass substrate at 50 °C in an aqueous medium by simple electrochemical deposition technique. The structural and phase purity of the Mn²⁺ doped FeS₂ thin films were investigated using XRD technique. The XRD analysis revelaed that the fabricated thin films were cubic structure along with the (200) plane preferential orientation. The diffraction peak slightly shifted towards lower 2θ values which confirmed that doping of Mn ions into FeS₂ host matrixes. The calculated band gap energy of Mn²⁺ doped FeS₂ thin films showed a red shift of absorption edge compared to undoped FeS₂ thin film. EIS indicated that Mn²⁺ doped FeS₂ thin films showed lower charge transfer resistance with better conductivity nature compared to undoped sample. Moreover, the photo electrochemical measurements carried out for the optimized Mn²⁺ doped FeS₂ thin film which revealed the faster migration of photo-induced charge-carriers. Electro catalytic activity of Mn-doped FeS₂ thin films were studied for the redox reaction of iodide/triiodide (I⁻/I₃⁻) by using cyclic voltammetry measurement.