Biofuels & Bioenergy

Direct carbon fuel cell (DCFC) is a type of fuel cell which produces electricity through electrochemical oxidation of solid carbon into carbon dioxide, without involving combustion reaction. The most promising advantage of DCFC is its remarkably high theoretical efficiency in converting chemical energy into electricity which is close to 100%. Its overall system efficiency taking into account of auxiliary losses is in the range of 60-70%, as compared to less than 40% for a Carnot Cycle. In this work, plant waste was tested as a sustainable carbon source for DCFC. The waste was pyrolyzed at different temperatures to produce biochar. Analytical techniques including XRD, microporous CO₂ adsorption, proximate and ultimate analyses were employed to characterize the biochar. The electrochemical performance of all samples in DCFC was also evaluated. The results shown that plant waste pyrolyzed at 600^oC yielded the highest power density. This superior performance was attributed to its abundance of carbon available as fuel source, and large numbers of active sites available for the electrochemical reaction. .