酚醛树脂基活性炭材料的制备及其电化学性能

以酚醛树脂（PF）为原料，聚乙二醇（PEG）为造孔剂，采用聚合物共混炭化及水蒸气活化法制备超级电容器电极用活性炭。通过热重（TG）分析探讨了PF、PEG及其共混物（PF-PEG）在升温过程中的热解行为，用N₂-BET法测试比表面积及其孔结构参数。通过测试恒流充放电、循环伏安和交流阻抗曲线分析其电化学性能，研究了活化温度、水蒸气流速及活化时间对活性炭孔结构及电化学性能的影响。结果表明，当活化温度为900℃、水蒸气流速为1 ml·min^-1、活化时间为2 h时制备的活性炭结构和性能相对较好，孔径主要分布在2 nm以下，比电容达到105.4 F·g^-1，具有良好的电容特性。

Preparation and electrochemical properties of PF-based activated carbon

Activated carbon serving as electrode materials for supercapacitors were prepared by a polymer blend carbonization and steam activation method using phenol formaldehyde resin (PF)as carbon precursor and polyethylene glycol（PEG）as pore-forming agent.Heating program was determined by the pyrolysis behavior of PF, PEG and their blend (PF-PEG)in the heating process characterized by the TG.The specific surface area and pore structure parameter of the activated carbon were calculated by the N₂-BET method.Galvanostatic charge-discharge, cyclic voltammetry and alternating current impedance were used to characterize electrochemical performance of activated carbon.Activation temperature, water vapor flow rate and activation time affected the pore structure and electrochemical performance of activate carbon.The results showed that with increasing activation temperature and increasing activation time, the capacitance increased.At activation temperature of 900℃, steam flow rate of 1 ml·min^-1 and activation time of 2 h, the structure and properties of prepared activated carbon were better.Its pore size was mainly smaller than 2 nm.With electrolyte solution 1 mol · L^-1 KOH/H₂O solution，its capacitance reached 105.4 F·g^-1 with a traditional three-electrode test system, and cycling performance was better.