Chemical synthesis and characterization of Mn3O4 thin films for supercapacitor application

A facile chemical bath deposition (CBD) technique has been used for the preparation of Mn3O4 thin films at room temperature. The structural, morphological, optical, wettability and electrical characterizations have been carried out by means of X-ray diffraction (XRD), Scanning electron micrograph (SEM), Fourier transform infrared spectrum (FTIR), optical absorption, contact angle and electrical resistivity studies of deposited films. The XRD pattern shows the tetragonal hausmannite structure of Mn3O4 thin film. The Mn3O4 formation was also confirmed from FTIR studies. SEM images showed that the substrate surface is uniformly covered with spherical beads-like architecture. The Mn3O4 film showed a direct optical band gap with energy 2.51 eV and hydrophilicity with water contact angle of 53°. The room temperature electrical resistivity of Mn3O4 thin film was found to be 1.6 × 102 Ω cm. Mn3O4 films when used in supercapacitor exhibited specific capacitance of 284 F g−1 in 1 M Na2SO4 electrolyte.