Thermal Decomposition Derived Nano Molybdenum Nitride For Robust Counter Electrode In Dye-Sensitized Solar Cells

The unique category of transition metal nitrides has an immense scope as an electron-driven catalyst in redox reactions. However, synthesizing metal nitrides without contamination is very challenging. The residues present in the catalyst might affect catalytic activity. This work reports a simple synthesis of contamination-free nano scale molybdenum nitride (Mo2N) powder by integrated wet chemical and thermal decomposition techniques at 800 degrees C. Systematic structural and morphological studies were done, which shows the spherical shape of gamma -Mo2N nanoparticles. Electrochemical and photovoltaic characteristics were studied using cyclic voltammetry, electrochemical impedance spectroscopy (EIS), Tafel polarization and J-V characteristics. As a result of high electrolyte diffusivity, less charge transfer resistance, high electrochemical stability and catalytic activity, the nano Mo2N based DSSCs exhibits 5.3 % efficiency, which is comparable to Pt-based device (6.4 %) fabricated under the similar condition that is 83.7 % of the performance offered by an expensive counter electrode. This simple synthesis method could enable low-cost mass production of Mo2N nanoparticles as counter electrodes in DSSC. The developed counter electrodes may be a suitable alternative for stable, efficient and low-cost DSSCs.