超级电容器MnO_2/CRF复合电极材料的制备及性能的研究

Study on the preparation and performance of MnO_2/CRF composite electrodes for the application of supercapacitor

以间苯二酚(R)和甲醛(F)为原料,碳酸钠(C)为催化剂,制备碳气凝胶(CRF),并以KMnO4和Mn(CH3COO)2.4H2O为原料,采用了化学沉淀法制备MnO2/CRF复合材料。用N2吸附、X射线衍射(XRD)和扫描电镜(SEM)对所制备的MnO2、CRF和MnO2/CRF复合材料进行了表征,结果表明碳气凝胶具有珍珠串式的无序多孔网络结构,所制备的MnO2为纳米级颗粒,复合材料为纳米级粉体。并对不同配比的MnO2/CRF复合材料的电化学性能进行了研究。循环伏安、恒流充放电实验表明了所制备的MnO2/CRF复合电极材料具有良好的可逆性和充放电性能。当MnO2含量为60%时,MnO2与碳气凝胶复合制成的新型电极材料具有226.3F/g的比电容,比碳气凝胶电极的比电容提高了1倍。此外,对复合电极的循环寿命进行了研究,表明复合电极具有良好的循环充放电性能。

In this paper,carbon aerogel was prepared by the polycondensation of resorcinol （R） with formaldehyde （F）.and sodium carbonate was added as a catalyst （C）. MnO2 powders for the application of supercapacitor was prepared by using KMnO4 and Mn（CH3COO）2 · 4H2O as raw materials,MnO2/CRF composite electrode materials were prepared by a chemical precipitation method. Physical properties of MnO2,CRF and MnO2/CRF were characterized by N2 adsorption,X-ray diffraction （XRD） and scanning electron microscopy （SEM）. The results showed that carbon aerogel is an amorphous material with a pearly network structure,the MnO2 possessed nanoscaled structure and the MnO2/CRF composite materials were nano-size particles. Electrochemical performances of the MnO2/CRF composite electrodes with different ratio were studied. Good electrochemical performances of MnO2/CRF composite electrodes were confirmed by cyclic voltammetry and galvanostatic charge/discharge measurement. The results indicated that MnO2/CRF composite electrodes have high reversibility and excellent charge-discharge property. However,when the loading amount of MnO2 was 60% ,the specific capacitance of MnO2/CRF could reach 226.3F/g,the capacitance of composite electrode was about two times larger than that ofcarbon aerogel electrode. Besides,this supercapacitor with MnO2/CRF composite electrodes had an ideal capacitance properties, good cycle life.