Enhanced waste Plastics-to-Power in situ conversion through iron oxide as pseudofuel in solid oxide fuel cells

Waste plastics -to -power conversion via fuel cells is very attractive for its potential to be efficient and ecofriendly. Here we report a solid oxide fuel cell (SOFC) operating directly on waste polyethylene terephthalate (PET) with significantly improved performance due to the modification of anode with iron oxide (Fe2O3) that functions as pseudofuel in its reduced form (FeO). The pseudofuel performance, namely the discharge capacity of FeO, was improved significantly by optimizing the structure of Fe2O3, and owing to the synergistic interaction of FeO with the anodic materials, i.e. silver and gadolinia doped ceria. A mechanism is proposed to reveal the synergistic effect of these materials in the discharge process. The maximum discharge capacity of 340 mAh/g for FeO was obtained, approaching 91 % of the theoretical value. Based on the optimized pseudofuel, the electrochemical performance of SOFCs directly fueled by waste PET was markedly enhanced: The peak power density of the cell increased from 115 to 320 mW cm -2, and the electric energy output of the PET fuel did from 0.0018 to 0.26 Wh/g (140 -fold more). This work shows that SOFCs with Fe2O3 modified Ag-based anode offer a promising platform for direct conversion of plastic waste to power in an efficient and green manner.