Study of derivatives of (E)-1-(3-aryl-1-phenyl-1H-pyrazol-4-yl)but-2-en-1-one for enhancing reduction efficiency of compost based microbial fuel cell

A series of α-, β-unsaturated ketone derivatives of four substituted pyrazoles were synthesised using Claisen-Schmidt condensation reaction and were characterised using Fourier-transform infrared (FTIR) spectroscopy, 1H nuclear magnetic resonance (NMR) and 13C NMR spectroscopy. Further, these derivatives were studied under application as an oxidising agent in a compost-based microbial fuel cell (cMFC) to enhance its reduction efficiency. Characterisation methods of cyclic voltammetry (CV), linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS) and chrono-amperometry (CS) were employed to analyse the behaviour of the coin-cell device with and without pyrazoles at the cathode. Concentration dependence of the best pyrazole out of the series was studied to optimise the device performance. The results indicate the enhancement in bio-electro-catalytic activity and output power density when the cathode of the cMFC is laced with pyrazoles. In addition, sustainability and stability of the device was also investigated, and study to confirm the role of micro-organisms in the compost was also performed.