Construction of 0D CeO2/2D MnO2 heterostructure with high electrochemical performance

Abstract The rational design of electrode material is crucial for the pursuing of energy storage device with high performance. Single active material always shows the limitation as electrode material, thus utilizing the synergistic effect between two components to construct the nanocomposite would be a good choice to optimize the electrochemical performance. In this work, a series of CeO 2 nanoparticles/MnO 2 nanosheets composites with diverse molar ratios are synthesized. 0D CeO 2 nanoparticles are homogeneously dispersed on the 2D MnO 2 nanosheets and the synthesis mechanism is studied in detail. MnO 2 nanosheets with a layered structure offer abundant ion transport channel and can shorten the ion transport path. Besides CeO 2 nanoparticles between the MnO 2 layers which avoiding the tight stack can further accelerate the ion diffusion and bring out more active sites. With the synergistic effect, the composite CeO 2 /MnO 2 shows the highest capacitance (580.1 F/g at a current density of 0.5 A/g) as well as an excellent cycling performance (95.8% capacitance retention after 10,000 cycles). The superior electrochemical performance makes this composite a promising candidate electrode material for supercapacitor application.