A high performance direct carbon solid oxide fuel cell – A green pathway for brown coal utilization

Abstract

Direct carbon solid oxide fuel cells (DC-SOFCs) are promising, all-solid-state, highly efficient and environment-friendly power generating devices fueled by solid carbons. In addition, utilization of real-world coal as fuel for DC-SOFC is an attractive topic, however, they still yield poor performance due to negative effect of impurities in coal. In order to utilize brown coal to generate electricity efficiently and environmentally, here we report a high-performance direct carbon solid oxide fuel cell that enables a green pathway for brown coal utilization. The cell consists of nano Al2O3 doped yttria-stabilized zirconia (YSZ) electrolyte supports and Ag-Gd0.1Ce0.9O2-δ as symmetrical composite catalyst electrodes. Fueled with raw brown coal and brown coal char at 850 °C separately, the cells can achieve maximum power densities of 211.4 and 221 mW cm−2, respectively. Furthermore, a stable discharging voltage and platform with the fuel utilization of 61.5% are demonstrated when brown coal char fueled DC-SOFC is operated under a constant current of 0.1 A.