Ultrasound-Microwave-Assisted Synthesis of MnO2 Supercapacitor Electrode Materials
Ultrasound-Microwave-Assisted Synthesis of MnO2 Supercapacitor Electrode Materials
复制标题
超声微波辅助合成MnO2超级电容器电极材料
DOI：
10.1021/ie5025485
复制
发表时间：
2014
影响因子：
4.2
通讯作者：
Lei Zhi-Gang
中科院分区：
文献类型：
--
作者：
Wang Ping;Zhao Yu-Jing;Wen Li-Xiong;Chen Jian-Feng;Lei Zhi-Gang
以三嵌段聚合物P123为软模板剂，采用超声-微波强化沉淀法合成了多孔二氧化锰。采用微波加热和超声分散相结合的方法制备的二氧化锰粒子具有疏松的球状网络结构，球内有直径4~5 nm的小孔，二次粒子之间有建筑状的中孔和大孔。用传统的热板加热或磁力搅拌代替微波加热或超声分散，可使疏松网状结构变得更坚固，颗粒更大，比表面积更小。循环伏安(CV)和恒流充放电测试结果表明，强化沉淀法制备的MnO2的放电比容量最高，达到∼214F/g，1000次循环后容量下降不大，5000次循环后容量下降可接受，进一步证实了微波加热和超声分散对合成性能较好的MnO2粒子的强化作用。
Porous manganese dioxide (MnO2) was synthesized via an ultrasound–microwave-intensified precipitation reaction with the soft template of triblock polymer P123. The MnO2particles prepared by combining microwave heating and ultrasonic dispersing showed a loose sphere-network structure with tiny pores 4–5 nm in diameter inside the spheres, as well as architectural mesopores and macropores among the secondary particles. The loose network structure became more solid with bigger particles and less surface area if the microwave heating or ultrasonic dispersing was replaced by conventional hot plate heating or magnetic stirring. The electrochemical properties examined by cyclic voltammetry (CV) and galvanostatic charge/discharge methods illustrated that the MnO2prepared with intensified precipitation had the highest discharge specific capacitance of ∼214 F/g and showed negligible capacitance decline after 1000 cycles and acceptable decline after 5000 cycles, which further confirmed the combined intensifying effects of microwave heating and ultrasonic dispersing on the synthesis of MnO2particles with higher performance.