A Cellulose Electrolysis Cell with Metal-Free Carbon Electrodes

Abstract

Biomass raw materials, including agricultural residues, collected weeds, and wood chips, are important feedstocks for hydrogen production. Numerous attempts have been made to electrolyze biomass directly or indirectly to hydrogen because these processes allow for the production of hydrogen with less power consumption than water electrolysis. However, expensive metal-based electrocatalysts are needed, especially for the cathode reaction, in the electrolysis cells. Results from the present study demonstrate the production of hydrogen directly from cellulose, using an optimal mesoporous carbon as the cathode in addition to a partially oxygenated carbon anode at a temperature of 150 °C, with an electrolysis onset voltage of ca. 0.2 V, a current density of 0.29 A cm−2 at an electrolysis voltage of 1 V, and a current efficiency of approximately 100% for hydrogen production. These characteristics were comparable to those recorded when using a Pt/C anode and cathode under the same conditions. The sp2 planes of the carbon allowed π electrons to be donated to protons at the cathode. In addition, the mesoporous structure provided a sufficient amount of sp2 planes on the surface of the cathode.