生物油分级多孔碳超级电容器电极材料的制备及性能

Preparation and properties of bio-oil hierarchical porous carbon electrode materials for supercapacitor

以稻壳生物油为碳源,氯化镁(MgCl_(2))为模板剂,采用草酸钾(K_(2)C_(2)O_(4))活化制备分级多孔碳(BOCs),研究了工艺参数对多孔碳物理化学特性的影响,并测试其电化学性能。结果表明,K_(2)C_(2)O_(4)作为活化剂可对碳骨架产生蚀刻效果,大幅增加碳的孔隙结构;MgCl_(2)作为模板可以改善活化效果并提高介孔率。最佳工艺参数下制得的BOC-3具备高比表面积(1961.1m^(2)/g)、高介孔率(47.25%)、高含氧量(15.0%,原子分数)的特点和三维泡沫结构。得益于这些特性的多重协同效应,BOC-3的质量比电容可达280F/g,5000次循环充放电后比电容保持率仍达到94.8%,具有优异的倍率性能和循环稳定性。本研究表明以MgCl_(2)为模板结合K_(2)C_(2)O_(4)进行活化的工艺,可作为从生物油制备高性能超级电容器用分级多孔碳的有效途径,有利于实现生物油的高价值利用。

The hierarchical porous carbons were prepared from rice husk bio-oil as carbon precursor by using magnesium chloride(MgCl_(2))as a template agent and potassium oxalate(K2C2O_(4))as activator.The effect of process parameters on the physicochemical properties and electrochemical properties of porous carbon was investigated.It was shown that K2C2O_(4) as an activator could etch the carbon skeleton and greatly increase the pore structure of carbon.MgCl_(2) template could improve the activation effect and increase the mesopore ratio.The BOC-3 prepared under the optimal activation conditions had a threedimensional foam structure,high specific surface area(1961.1m^(2)/g),high mesoporosity(47.25%)and high oxygen content(15.0%).Benefiting from the multiple synergistic effects of these properties,BOC-3 has a mass specific capacitance of 280F/g,and a specific capacitance retention rate of 94.8%after 5000 cycles of charging and discharging.BOC-3 had excellent rate performance and cycle stability.This study revealed that the combination of K2C2O_(4) activator and MgCl_(2) template could be used as an efficient route to fabricate hierarchical porous carbons for high-performance supercapacitors from bio-oil,which was conducive to the high value utilization of bio oil.