A molten salt route to binder-free CeO2 on carbon cloth for high performance supercapacitors

Cerium oxide is one of the most abundant and environment-benignity rare earth oxides, which is thus of interesting to explore its feasibility to serve as a safe and efficient candidate for supercapacitor electrodes. We report herein a facile one-step molten salt method to synthesize CeO2 nanoparticles abundant in surface oxygen vacancies, which are directly grown on a carbon cloth (CeO2@CC). The CeO2@CC exhibits a high specific capacitance of 811.5 mF cm(-2) at the current density of 5 mA cm(-2) in -0.8-0 V, with a good capacitance retention of 86.3 % at 5 mA cm(-2) after 10,000 cycles in 6 M KOH aqueous electrolyte. When assembled with a Co3O4@CC positive electrode, the Co3O4@CC//CeO2@CC asymmetric supercapacitor achieves an energy density of 0.11 mWh cm(-2 )at a power density of 3.25 mW cm(-2). Both the abundant oxygen vacancies and the conductive carbon cloth contribute to the electrochemical performance. This work suggests that CeO2 could be a candidate material for high performance supercapacitors.

Automated summary

This study reports a method to synthesize CeO2 nanoparticles abundant in surface oxygen vacancies using a one-step molten salt method, and grows them directly on a carbon cloth as electrode material. The CeO2@CC exhibits a high specific capacitance and good capacitance retention, indicating that CeO2 could be a candidate material for high-performance supercapacitors.