废弃酚醛树脂保温材料基电极材料多孔炭的制备及构效关系

The Preparation and Structure⁃Activity Relationship of the Electrode Material Porous Carbon Based on Waste Phenolic Resin Thermal Insulation Material

低成本高效杂原子掺杂多孔炭材料在高性能超级电容器的发展中起着至关重要的作用。酚醛树脂基泡沫保温板含有氮、氧元素,是制备高效多孔炭的“零”成本原料。本工作以废弃酚醛树脂外墙保温板为原料,采用化学活化法制备了用于超级电容器电极材料的多孔炭。结果表明,获得最优电化学性能的工艺条件为:活化剂KOH,碱炭质量比2∶1,活化温度600℃,活化时间2 h。该条件下制备的多孔炭的比表面积为960 m^(2)/g,孔结构以微孔和介孔为主;XRD和Raman表征发现多孔炭石墨化程度较低,主要为无定型碳结构;XPS和FTIR检测到多孔炭含有氮、氧元素。对于多孔炭的电化学性质,以3 mol/L KOH为电解液、电压窗口为-1~0 V、电流密度为0.5 A/g时,三电极系统测试得到质量比电容为315 F/g;在4 A/g的电流密度下,对称超级电容器经过20000圈循环后电容保持和库仑效率仍接近100%。在15 A/g的高电流密度下,对称两电极系统测试能量密度为27.1 Wh·kg^(-1),功率密度为7100 W·kg^(-1)。与其他单纯碳材料相比,废弃酚醛树脂基保温板多孔炭展示出更优异的电化学性能。

Low⁃cost and efficient heteroatom⁃doped porous carbon materials play an important role in the development of high⁃performance supercapacitors.Phenolic resin based foam insulation board containing nitrogen and oxygen elements,is‘Zero’cost raw materials for preparing efficient porous carbon.In this work,porous carbon for electrode material of supercapacitor was prepared from waste phenolic resin insulation board by chemical activation method.The results show that the optimum conditions of electrochemical performance are as follows:KOH activator,alkali⁃carbon mass ratio 2∶1,activation temperature 600℃,activation time 2 h.The structures of porous carbon with high specific surface area of 960 m^(2)/g are mainly micropores and mesopores under such circumstance.XRD and Raman analyses show that the graphitization degree of porous carbon is low,and its structure is mainly amorphous.What's more,through XPS and FTIR nitrogen and oxygen elements are detected in porous carbon.In the three⁃electrode 3 mol/L KOH aqueous solution test system,with the voltage window was-1-0 V and the current density was 0.5 A/g,the mass ratio capacitance of porous carbon can be as high as 315 F/g.Meanwhile,the capacitance retention and coulomb efficiency of the symmetric supercapacitor are still close to 100%after 20000 cycles at the current density of 4 A/g.At the high current density of 15 A/g,the energy density of 27.1 Wh·kg^(-1) and the power density of 7100 W·kg^(-1) were measured by the symmetric two⁃electrode system.Compared with other simple carbon materials,the porous carbon of waste phenolic resin insulation board shows better electrochemical performance.