Investigation of solid bio-membrane based on corn biomass as a proton-conducting bio-electrolyte

A solid bio-electrolyte has been prepared by blending the extract of the silk part of the corn biomass (corn silk extract, CSE), polyvinyl alcohol (PVA) and NH 4 HCO 2 as the charge carrier via the solution casting technique. This biodegradable electrolyte is optimized by the AC impedance analysis for the composition 1 g PVA + 0.9 g CSE + 0.5 wt% NH 4 HCO 2 from their maximum conductivity values. The highest ionic conductivity for this optimized composition at room temperature is 3.302×10 –3 S cm –1 . This bio-electrolyte is then characterized by X-ray diffraction technique, Fourier transform infrared spectroscopy, differential scanning calorimetry, transference number analysis and electrochemical impedance spectroscopy. A primary proton-conducting battery was constructed with an output circuit voltage of 1.83 V at room temperature. A single stack PEM fuel cell has been constructed with the bio-electrolyte (0.9 g CSE + 1 g PVA + 0.5 wt% NH 4 HCO 2 ) and obtained an output circuit of 480 mV. This work implies the possibility of the development of an electrolyte from a biodegradable and renewable source for energy storage applications. Graphical abstract Synopsis : A bio-membrane from Corn biomass has been developed by blending the extract of the corn silk with polyvinyl alcohol and then a bio-electrolyte has been cast by adding ammonium formate as an ionic dopant. A primary proton cell with an output voltage of 1.83 V is fabricated with the bio-electrolyte.