介孔炭材料及其水系电解液的制备与电化学性能研究

发布时间：2018-06-04 04:06

本文选题：介孔炭 + 直接碳化法　；参考：《兰州理工大学》2017年硕士论文

【摘要】：随着超级电容器的性能被逐渐拓展,其高功率密度、长循环寿命和经济环保的优势愈发引人瞩目。但能量密度低这一不足使其无法替代Li电池等传统能源储备/供应器件。电极材料与电解液是影响超级电容器性能的关键因素。炭电极材料与水系电解液具有环境友好性、经济效益性被广泛应用于超级电容器。由于炭材料较低的比电容和水系电解液较低的稳定电压窗口,使得超级电容器能量密度较低。为了提高超级电容器能量密度,本文通过优化炭材料孔隙结构提高比电容,并制备具有高稳定电压窗口的水系电解液,改善超级电容器低能量密度的这一弊端。提高炭材料比电容,增大了水系电解液电压窗口,提高了超级电容器能量密度。1、采用柠檬酸铁铵有机复合盐一步炭化制备自掺氮介孔炭材料。自掺氮介孔炭材料FBNC-700具有大的BET表面(1021 m2 g-1),双峰孔结构(孔分布约在2 nm以及5-15 nm之间)和自掺氮(氮含量为3.86%),其比电容达到223 F g-1。2、考察了酒石酸钾钠溶液作为水系电解液的可行性。酒石酸钾钠溶液稳定电压窗口为1.3 V(-0.8 V-0.5 V)。通过二电极测试,FNBC-700在2 M酒石酸钾钠溶液中0.5 A g-1下比电容为97 F g-1。实验结果表明:2 M酒石酸钾钠溶液具有优异的电化学性能,可作为一种新型水系电解液。3、考察了醋酸钠溶液作为水系电解液的可行性。醋酸钠溶液稳定电压窗口为1.8 V(-1.1 V-0.7 V),FNBC-700在1.5M醋酸钠溶液三电极测试中比电容为254 F g-1。二电极测试中,1.5 M醋酸钠中FBNC-700的能量密度较在1 M H2SO4性能更为优异。实验结果表明:1.5 M醋酸钠溶液可成为一种具有高稳定电压窗口的新型水系电解液。
[Abstract]:The advantages of high power density, long cycle life and economic and environmental protection are becoming more and more attractive as the performance of supercapacitors is gradually expanded. However, the low energy density makes it impossible to replace the traditional energy storage / supply devices such as Li batteries. Electrode materials and electrolyte are the key factors affecting the performance of supercapacitors. Carbon electrode materials and aqueous electrolyte have environmental friendliness and economic benefits are widely used in supercapacitors. Because of the lower specific capacitance of carbon material and the lower stable voltage window of water electrolyte, the energy density of supercapacitor is lower. In order to improve the energy density of supercapacitors, this paper improves the low energy density of supercapacitors by optimizing the pore structure of carbon materials and preparing water electrolyte with high voltage window. The specific capacitance of carbon material was increased, the voltage window of electrolyte was increased, and the energy density of supercapacitor was increased. The nitrogen-doped mesoporous carbon material was prepared by one step carbonization with ferric ammonium citrate organic compound salt. Self-nitrogen-doped mesoporous carbon (FBNC-700) has a large BET surface of 1021 m2 g ~ (-1), a bimodal pore structure (pore distribution of about 2 nm and 5-15 nm) and self-doped nitrogen (the nitrogen content is 3.86), and its specific capacitance is up to 223F g-1.2. The potassium sodium tartrate solution as a kind of sodium tartrate was investigated. Feasibility of electrolyte in water system. The stable voltage window of potassium sodium tartrate solution is 1.3 V ~ (-1) V ~ (-0.8) V ~ (0.5) V ~ (-1). The specific capacitance of FNBC-700 was 97 F g -1 in 2 M potassium sodium tartrate solution. The experimental results show that potassium sodium tartrate solution has excellent electrochemical performance and can be used as a new water electrolyte. The feasibility of sodium acetate solution as water electrolyte was investigated. The voltage window of sodium acetate solution is 1.8 V ~ (-1) V ~ (-1) V ~ (0.7) V FNBC-700. The specific capacitance of FNBC-700 is 254 F g ~ (-1) in 1.5m sodium acetate solution. The energy density of FBNC-700 in 1.5 M sodium acetate is better than that in 1 M H2SO4. The experimental results show that the sodium acetate solution of 1. 5 M can become a new type of electrolyte with high voltage window.
【学位授予单位】：兰州理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM53;O646

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