Electrochemical hydrogen storage in carbon nitride electrode using modified reversible polymer electrolyte membrane fuel cell

Abstract

The human population is now through a process of evolution, whereby there is a gradual shift towards the adoption and utilization of alternative energy sources and technologies for energy storage. In this transition process non-availability of renewable energy sources round the clock is one of the key hurdles. It is possible to meet continuous energy demands by storing excess renewable energy as hydrogen. The presented experimental investigation focuses on a modified reversible fuel cell (MRFC) with a solid carbon-based substance (carbon nitride) integrated into it as a host for electrochemical hydrogen storage. The method for electrode fabrication from carbon nitride powder and PTFE binder and a lab-scaled MRFC is disclosed. The developed MRFC with an integrated hydrogen storage electrode is put through electrochemical testing, and the results are presented. Galvanostatic charging and discharging is done, and the results are examined to ascertain the electrode's electrochemical hydrogen storage capacity. The electrochemical hydrogen storage capacity of the porous carbon nitride electrode is found to be 1.15 wt%, which is comparable to intermetallic metal hydride-based hydrogen storage mediums viz. AB2 and AB5. The obtained results showed the feasibility of a MRFC with an integrated carbon nitride-based hydrogen storage electrode, making it the first device of its kind. Besides, porous carbon nitride is proved to be a potential candidate for reversible electrochemical hydrogen adsorption. This will contribute to the clean energy sector and surely a step forward toward hydrogen economy.