铁、铋化合物的制备及其电化学性能研究

发布时间：2018-04-22 15:00

  本文选题：β-FeOOH + BiFeO_3　； 参考：《湘潭大学》2017年硕士论文

【摘要】：随着经济的飞速发展,传统化石能源的短缺和环境污染已成为当今社会迫切需要解决的严峻问题,因此以超级电容器和碱性二次电池为代表的清洁可再生的储能器件已经成为学者研究的重点。本文制备出β-FeOOH、Bi Fe O_3、La掺杂Bi_2O_3等三种电极材料,并与活性炭(C)或Ni(OH)2组装成C//β-FeOOH非对称超级电容器、BiFeO_3//Ni(OH)2碱性二次电池和La-Bi_2O_3//Ni(OH)2碱性二次电池以研究所制备材料的电化学性能。本论文的主要内容如下:1.以FeCl_3为原料、水和乙二醇的混合液为溶剂,通过水热法制备了β-FeOOH材料,并将其组装成C//β-FeOOH非对称超级电容器,研究其电化学性能。通过正交实验得出最佳的制备条件为:FeCl_3浓度为0.10 mol L-1,乙二醇与水的体积比为1:6,水热温度为145℃,水热时间为6 h。该条件下制备的β-FeOOH材料在0.5 A g-1电流密度下,其比电容为642 F g-1,800次循环后保持初始比电容的72%。2.以Bi(NO_3)_3及Fe(NO_3)_3为原料、酒石酸为络合剂,通过自蔓延燃烧法制备了BiFeO_3材料,将其与商品化Ni(OH)2正极材料组成BiFeO_3//Ni(OH)2碱性二次电池,研究其电化学性能。利用正交实验制备了不同条件下的BiFeO_3材料,得出最佳制备条件为:Bi(NO_3)_3浓度为0.10 mol L-1,反应温度为500℃,反应时间为5 h,升温速率为5℃min-1。该材料在1 A g-1电流密度下,其比容量为199mAh g-1,500次循环后保持初始比容量的62%。在此最佳制备基础上,采用乙醇作为溶剂配制Bi(NO_3)_3和Fe(NO_3)_3的混合溶液,制备出性能更加优良的BiFeO_3材料,在1 A g-1电流密度下其比容量高达238 mAh g-1,500次循环后保持初始比容量的79%。3.以Bi(NO_3)_3和La(NO_3)_3为原料、氢氧化钠为沉淀剂,通过共沉淀法得到La掺杂Bi(OH)_3,通过条件实验得出最佳掺杂比例为nLa/nBi=0.075。在最佳掺杂比例的基础上通过进一步地高温煅烧处理制得La掺杂Bi_2O_3,将其与商品化Ni(OH)2电极材料组装成La-Bi_2O_3//Ni(OH)2碱性二次电池。所制备的La掺杂Bi_2O_3材料在1 A g-1的电流密度下其比容量为240 mAh g-1,500次循环后保持初始比容量的86%。
[Abstract]:With the rapid development of economy, the shortage of traditional fossil energy and environmental pollution has become a serious problem that needs to be solved urgently. Therefore, clean and renewable energy storage devices, represented by supercapacitors and alkaline secondary batteries, have become the focus of research. In this paper, three kinds of electrode materials such as 尾 -FeOHX BiFeO3La doped Bi_2O_3 have been prepared and assembled with activated carbon (C) or Ni(OH)2 to form C / 尾 -FeOOH asymmetric supercapacitors BiFeO-2 alkaline secondary battery and La-Bi_2O_3//Ni(OH)2 basic secondary battery to study the electrochemical properties of the prepared materials. The main contents of this thesis are as follows: 1. 尾 -FeOOH materials were prepared by hydrothermal method using FeCl_3 as raw material and mixed solution of water and ethylene glycol as solvent. The materials were assembled into C / 尾 -FeOOH asymmetric supercapacitors. The electrochemical properties of 尾 -FeOOH supercapacitors were studied. The optimum preparation conditions were obtained by orthogonal experiment: the concentration of 1: FeCl3 was 0.10 mol / L ~ (-1), the volume ratio of ethylene glycol to water was 1: 6, the hydrothermal temperature was 145 鈩，

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