Abstract:

The porous carbon materials were synthesized from the straw by hydrothermal method coupled with KOH activation, of which the structure and morphology were characterized. The electrochemical properties of the porous carbon materials were evaluated by the cyclic voltammetry, galvanostatic charge/discharge and AC impedance tests in Li₂SO₄ electrolyte with different concentrations using a three electrodes electrochemical system. The results showed that the porous carbon materials have the best electrochemical performances in 0.5 mol·L^-1 Li₂SO₄ electrolyte. The specific capacitance of porous carbon materials can reach 224 F·g^-1 at a current density of 0.5 A·g^-1, with specific capacitance retention of over 94.1% after the 1500 charge/discharge cycles, which indicates a good cycle characteristics.

Key words: biomass, activation, hydrothermal method, porous carbon, electrochemistry

摘要：

以生物质秸秆为碳源，利用水热结合KOH活化法制备了多孔碳材料，对其结构与形貌进行了表征。采用三电极体系，在不同浓度的Li₂SO₄电解液中，对多孔碳电极进行循环伏安、恒电流充放电和交流阻抗测试。结果表明，在0.5 mol·L^-1的Li₂SO₄电解液中，秸秆基生物质碳材料呈现出较好的电化学性能。当电流密度为0.5 A·g^-1时，比电容可达224 F·g^-1；经1500次充放电测试后，比电容保持率高达94.1%，循环性能良好。

关键词: 生物质, 活化, 水热法, 多孔碳, 电化学