Highly efficient direct carbon solid oxide fuel cells operated with camellia oleifera biomass

Direct carbon solid oxide fuel cells (DC-SOFCs), energy conversion devices with an all-solid-state structure, utilize solid carbon as a fuel to generate electricity in a green and efficient manner. Recently, the use of biomassderived carbon as a DC-SOFC fuel has become a key research topic owing to the abundance and renewability of biomass. Thus far, for the majority of studies, an anaerobic pyrolysis process is usually needed for converting the biomass to biochar prior to applying DC-SOFCs. In this study, DC-SOFCs were assembled with perovskite-type La0.9Sr0.1Ga0.8Mg0.2O3-delta (LSGM) and Ag-Gd0.2Ce0.8O2-delta as the electrolyte and electrodes, respectively. The electrochemical performance and stability were evaluated for two types of DC-SOFCs: those filled with Camellia oleifera shell biomass as the fuel and those filled with biochar derived from the biomass. The biomass-filled DCSOFC achieved a maximum power density of 306 mW cm-2 at 800 degrees C, which is close to that of the biochar-filled DC-SOFC (317 mW cm-2). Moreover, discharge test results of constant current indicate that biomass-filled DCSOFCs have higher fuel utilization. This study verifies the feasibility and potential of loading biomass directly into DC-SOFCs as a carbon source, and reveals that, compared with DC-SOFCs operated with biochar, biomassfilled DC-SOFCs can deliver remarkable electrochemical performance and stability. Thus, a simpler and more convenient way to generate electricity through efficient and clean utilization of biomass energy is identified.

Automated summary

This study verifies the feasibility of directly loading biomass into DC-SOFCs as a carbon source, and reveals that biomass-filled DC-SOFCs can deliver remarkable electrochemical performance and stability compared with DC-SOFCs operated with biochar. It provides a simpler and more convenient way to generate electricity through efficient and clean utilization of biomass energy.