Synthesis of electro-active manganese oxide thin films by plasma enhanced chemical vapor deposition

Abstract The good stability, cyclability and high specific capacitance of manganese oxide (MnO x ) has recently promoted a growing interest in utilizing MnO x in asymmetric supercapacitor electrodes. Several literature reports have indicated that thin film geometries of MnO x provide specific capacitances that are much higher than bulk MnO x powders. Plasma enhanced chemical vapor deposition (PECVD) is a versatile technique for the production of metal oxide thin films with high purity and controllable thickness. In this work, MnO x thin films deposited by PECVD from a methylcyclopentadienyl manganese tricarbonyl precursor are presented and the effect of processing conditions on the quality of MnO x films is described. The film purity and oxidation state of the MnO x films were studied by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Preliminary electrochemical testing of MnO x films deposited on carbon fiber electrodes in aqueous electrolytes indicates that the PECVD synthesized films are electrochemically active.