厚层3D多孔石墨化活性木源碳电极制备及电化学性能研究

Preparation and Electrochemical Performance of Thick-layer 3D Porous Graphitized Activated Wood Carbon Electrode

通过简单的真空辅助催化法,首次一步实现对具有超大长径比的厚层3D多孔木源碳电极进行石墨化和活化的协同处理,首次完成厚层木源碳管壁打孔.该方法在增加木源碳电极材料的孔结构和比表面积的前提下,提高该电极材料的石墨化程度,从而,使其成为具有优异电化学性能的厚层双电层电极材料.经SEM、TEM以及Raman表征可知,该方法有效实现了催化剂溶液在基底孔道内壁的均匀附着,有效克服木材管道中管道内压对基底前处理和活化石墨化效果的影响.结合电化学测试得知,该厚层木源碳电极经过活化和石墨化协同处理后,样品的石墨化程度和倍率性能较CAWC(CO2活化电极)和WC(初始碳电极)得到显著提高,其中,ID/IG值依次为:0.9(AGWC),1.05(CAWC),1.17(WC).电流密度从0.5 A/g增大至5 A/g后,样品AGWC倍率性能较样品CAWC和WC的提高了近1.5倍和2倍.结果表明,该方法能够实现对具有超大长径比的厚层3D多孔结构的电极材料进行活化石墨化处理,具有一定的普适性,为厚层高密度石墨化活性碳电极的制备提供技术支持.

By a simple vacuum-assisted catalytic method, the 3 D porous thick wood-carbon electrode with large aspect ratio is simultaneously graphitized and activated for the first time. Meanwhile, it is also the first time that pipe wall of the thick wood-derived carbon has been successfully punched. The pore structure, specific surface area and graphitization degree of wood-carbon electrode are significantly improved, therefore, the material become a thick electric double layer capacitor material with excellent electrochemical performance. According to SEM, TEM, and Raman tests, the catalyst solution uniformly adhere to the inner wall of the pores of the substrate, effectively decreasing the influence of the internal pipeline pressure in the wood pipeline on the pretreatment of the substrate and activation graphitization. Combined with electrochemical tests, it is known that the electrochemical performance and graphitization degree of AGWC is better than that of CAWC(CO2 activated electrode) and WC(initial carbon electrode). The ID/IG ratios of samples are 0.9(AGWC), 1.05(CAWC) and 1.17(WC). When current density increases from 0.5 A/g to 5 A/g, the rate performance of the AGWC is 1.5 times and 2 times higher than those of the CAWC and WC. The results show that the method can achieve the cooperative graphitization and activation of the thick layer 3 D porous structured electrode materials of large aspect ratio in one step. The technology has certain universality, and it also provides technical support for the preparation of thick-layer graphitized activated carbon electrode.