A high-performance direct biomass fuel cell utilizing red bean shell as fuel

The direct carbon solid oxide fuel cell (DC-SOFCs) is a new technology for clean and efficient use of carbon resources to generate electricity, which has the advantages of high efficiency and wide fuel flexibility. Recently, DC-SOFCs using biomass as fuel have attracted tremendous attention due to the abundant reserves which are usually derived from plant. However, the biomass-based fuel cells scarcely deliver satisfactory performance because of low carbon content and high proportion of impurities. Here, a high-performance direct carbon solid oxide fuel cell using red bean shell biomass and its derived biochar is reported. Ag-Gd_0.2Ce_0.8O_2-δ and La_0.9Sr_0.1Ga_0.8Mg_0.2O_3-δ (LSGM) are used as symmetric electrode and electrolyte materials, respectively. At 850 ℃, the red bean shell biochar fueled cell exhibits an open circuit voltage of 1.08 V and a peak power density of 719 mW cm⁻², while the cell with biomass fuel provides 1.03 V and 619 mW cm⁻². The remarkable performance is attributed to the rich mesoporous structures and abundant reverse Boudouard reaction catalysts of K. This study demonstrates the feasibility and potential of high performing direct carbon fuel cells using specific biomass, realizing green and efficient utilization of biomass.