Defect-rich CeO in a hollow carbon matrix engineered from a microporous organic platform: a hydroxide-assisted high performance pseudocapacitive material.

A microporous organic polymer (MOP) was utilized for the engineering of nanoparticulate CeO in a hollow carbon matrix (H-C/CeO). After CeO nanoparticles were incorporated into a hollow MOP platform (H-MOP) through the decomposition of cerium acetate, successive carbonization produced H-C/CeO. The redox feature of defective CeO in a conductive carbon matrix induced promising pseudocapacitive behavior. In particular, the H-C/CeO showed excellent electrochemical performance in an alkaline electrolyte (KOH), due to the hydroxide ion-assisted redox behavior of defective CeO. H-C/CeO-3 with an optimized amount of CeO showed specific capacitances of up to 527 (@0.5 A g) and 493 F g (@1 A g). Even at high current densities of 10 and 20 A g, the H-C/CeO-3 maintained high capacitances of 458 and 440 F g, respectively. After 10 000 cycling tests, the H-C/CeO-3 retained the 94-95% capacitance of the first cycle.