表面改性对活性炭孔结构及热电转换性能的影响

为探究表面改性对活性炭孔结构及热电转换性能的影响,使用HNO_3和KOH在不同条件下对活性炭进行表面改性,用N2吸附法和XRD图谱表征活性炭改性前后孔结构和石墨化程度的变化。结果表明,改性后活性炭的比表面积和孔容提高,平均孔径减小,并存在石墨晶体结构。干法改性活性炭的比表面积和总孔容由1 077.880m~2/g和0.763cm~3/g分别增加到1 635.268m~2/g和1.128cm~3/g,并且微孔的孔容增加。改性处理可以去除活性炭中的杂质。分别以改性前后活性炭为材料制备固体电极,KCl为电解液,测试活性炭电极的热电转换性能,发现改性后活性炭具有更高的热电转换性能。

Effects of surface modification on the porous structure and thermal-electric energy conversion of activated carbon

In order to explore the effect of surface modification on pore structure and thermal-electric energy conversion of activated carbon,activated carbons were first modified by surface treatment using HNO3 and KOH under different conditions.The pore structure and graphitic-type structure of the activated carbons were characterized by N2 adsorption and XRD.The specific surface area and pore volume of the activated carbon are significantly increased by the surface treatments,while the average pore size and presence of graphite crystal structure are slightly affected.For the dry modification method,the specific surface area and pore volume are increased from 1 077.880 m2/g and 0.763 cm3/g to 1 635.268 m2/g and 1.128 cm3/g,respectively.Furthermore,after modification,the micropore volume is increased and the impurities of the activated carbon are removed.The performance of thermal-electric energy conversion of the activated carbon is tested by using the activated carbon as solid electrode materials and KCl solution as electrolyte,which shows the treated activated carbon has better performance.