Nanostructured fuel electrodes for low-temperature proton- and oxygen-ion-conducting solid oxide cells

Solid oxide cells (SOCs) are attractive electrochemical energy conversion/storage technologies for electricity/green hydrogen production because of the high efficiencies, all-solid structure, and superb reversibility. Nevertheless, the widespread applications of SOCs are remarkably restricted by the inferior stability and high material costs induced by the high operational temperatures (600–800 °C). Tremendous research efforts have been devoted to suppressing the operating temperatures of SOCs to decrease the overall costs and enhance the long-term durability. However, fuel electrodes as key components in SOCs suffer from insufficient (electro)catalytic activity and inferior impurity tolerance/redox resistance at reduced temperatures. Nanostructures and relevant nanomaterials exhibit great potential to boost the performance of fuel electrodes for low-temperature (LT)-SOCs due to the unique surface/interface properties, enlarged active sites, and strong interaction. Herein, an in-time review about advances in the design and fabrication of nanostructured fuel electrodes for LT-SOCs is presented by emphasizing the crucial role of nanostructure construction in boosting the performance of fuel electrodes and the relevant/distinct material design strategies. The main achievements, remaining challenges, and research trends about the development of nanostructured fuel electrodes in LT-SOCs are also presented, aiming to offer important insights for the future development of energy storage/conversion technologies.