Synthesis and electrochemical properties of Er/α-MnO2 microspheres for supercapacitors application

• Published in: Ionics 2019-08, Vol.25 (8), p.3867-3873
• Main Authors: Lin, Hua, Zhang, Meng, Miao, Jie, Li, Lu, Xin, Kaiyao, Liao, Xingyuan, Feng, Zhihao
• Format: Article
• Language: English
• Subjects: Chemical synthesis; Chemistry; Chemistry and Materials Science; Condensed Matter Physics; Crystal structure; Current density; Electrochemical analysis; Electrochemistry; Energy Storage; Manganese dioxide; Microspheres; Morphology; Optical and Electronic Materials; Organic chemistry; Original Paper; Renewable and Green Energy; Valence
• ISSN: 0947-7047; 1862-0760
• DOI: 10.1007/s11581-019-02939-0

Er-doped α-MnO 2 (Er/α-MnO 2 ) microspheres were successfully synthesized via a chemical process. The various techniques were used to investigate the crystal structures, morphologies, valence states, and electrochemical performances of the as-prepared materials. The results showed that Er can be doped into the lattice of α-MnO 2 as Er 3+ to distinctly affect the structure of α-MnO 2 . The as-obtained Er(1.5 at.%)/α-MnO 2 presented the most optimized structure with a surface composed of many regular layered triangles. The specific capacitance of Er(1.5 at.%)/α-MnO 2 electrodes reached 224.3 F g −1 at a current density of 0.25 A g −1 with a capacity retention ratio of 93.7% after 2000 cycles at a current density of 1.0 A g −1 . The values were higher than those of α-MnO 2 synthesized under the same conditions. Overall, these findings look promising for future applications of rare elements in modified MnO 2 .