刚性骨架COS-NMC材料制备及其电化学性能研究

以壳寡糖(COS)为碳前驱体,三嵌段共聚物(F127)和正硅酸乙酯(TEOs)为模板剂,通过溶胶-凝胶法制备了一种用于超级电容器的原位氮掺杂介孔碳材料(COS-NMC-x)。借助质谱仪、TG-DTG、XRD、Raman光谱、N₂吸附/脱附、XPS、FT-IR、亲水性以及电化学评价等手段对材料进行了表征,以研究材料的物化性质和电化学性能。结果表明,COS-NMC-x材料的比表面积、孔容、氮原子数分数随超声时间的增加呈先增后减的趋势,当超声时间为15 min时,样品的比表面积、孔容、氮原子数分数到最大,接触角最小,分别为144.94 m²·g^-1、0.19 cm³·g^-1、7.59%和23.16°。同时对COS-NMC-x进行了电化学性能评价,在电流密度为0.5 A·g^-1时,样品的比电容为189 F·g^-1,远高于同组其他材料,说明较大的孔隙结构和氮原子数分数等有利于材料的电化学性能提升。在10 A·g^-1下经过5 000次循环之后,该材料的电容保持率达到114%,表现出良好的电化学性能,在超级电容器应用方面展现出巨大的应用潜力。

Preparation and Electrochemical Properties of Rigid Skeleton COS-NMC Material

An in-situ nitrogen-doped mesoporous carbon material (COS-NMC-x) for supercapacitors was prepared by sol-gel method using chitosan oligosac charide (COS) as carbon precursor, triblock copolymer (F127) and ethyl orthosilicate (TEOs) as templating agent. The material was characterized by means of mass spectrometer, TG-DTG, XRD, Raman spectra, N₂ adsorption/desorption, XPS, FT-IR, hydrophilic and electrochemical evaluation to study the physical and chemical properties and electrochemical performance of the material. The results show that the performance parameters (specific surface area, pore volume and nitrogen atomic number fraction) of COS-NMC-x material tend to increase first and then decrease with the increase of ultrasound time, when the ultrasound time is 15 min,the specific surface area, pore volume and nitrogen atomic number fractionof sample reach the maximum, and the contact angle is the minimum, which are 144.94 m²·g^-1, 0.19 cm³·g^-1, 7.59% and 23.16°, respectively. At the same time, the electrochemical performance of COS-NMC-x was evaluated. The results show that, at a current density of 0.5 A·g^-1, the specific capacitance of sample is 189 F·g^-1, which is much higher than other materials in the same group, indicating that the larger pore structure and nitrogen atomic number fraction are beneficial to the improvement electrochemical performance of the material. After 5 000 cycles at 10 A·g^-1, the capacitance retention rate of sample reaches 114%, exhibiting good electrochemical performance and showing great application potential in supercapacitor applications.