Carbon assisted water electrolysis for hydrogen generation

Carbon Assisted Water Electrolysis (CAWE) is an energy efficient process in that $H2$ can be produced at lower applied voltage (∼1.0 V) compared to nearly 2.0 V needed for ordinary water electrolysis for the same $H2$ evolution rate. In this process, carbon is oxidized to oxides of carbon at the anode of an electrochemical cell and hydrogen is produced at the cathode. These gases are produced in relatively pure state and would be collected in a separate chamber. In this paper, we present the results of influence of various operating parameters on efficiency of CAWE process. The results showed that $H2$ can be produced at applied voltages E_o as low as 1.0V (vs. SHE) and its production rate is strongly dependent on the type of the carbon used and its concentration in the electrolyte. It has also been found that the performance of CAWE process is higher in acidic electrolyte than in alkaline electrolyte.