Enhancing the splitting efficiency of water molecules using conductive nanomaterials
Efforts are being made world over not just to minimize wastage of energy, but also pioneer new sources. The world faces a race against time to develop a sustainable source of energy before we run out of fossil fuels on which we are heavily dependent. Research is being carried to efficiently harvest the energy from renewable sources such as the sun, wind, falling water, tides, and other physical and chemical means. Hydrogen is another candidate that can solve our problems, being extremely useful in running fuel cells, motors and generators. Hydrogen can be obtained from a number of ways, one of which is electrolysis. This research is aimed at increasing the hydrogen production rate of water via electrolysis by adding nanomaterials to the electrolyte, and comparing the resultant rate of hydrogen production to that when there are no nanomaterials present. This comparative study helps in ascertaining the effectiveness of the nanomaterial involved. Graphene, MWCNT and Indium Tin Oxide (ITO) nanoparticles are dispersed in water using gum Arabic as a surfactant, and kept in constant motion using a magnetic stir bar. On passage of DC current, hydrogen and oxygen are obtained at the two electrodes, where the amounts are recorded and compared. For graphene, the maximum increase in HPR was close to 100%, with significant increases in each scenario tested. MWCNT performed the best of the three, with a maximum increase in HPR of about 170%, and significantly higher HPRs in most cases compared to graphene. The addition of ITO had adverse effects, or constricting the rate to almost zero, although higher concentrations showed significant increases at lower voltages. Some other factors such as acid concentration and temperatures were also studied. Addition of acid increases the concentration of ionic activators, causing an increase in the HPR with gradual increases in concentration. The same was observed for higher temperatures.
Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering