CoFe-PBA衍生过渡金属基纳米材料的电化学性能研究

发布时间：2018-06-04 02:28

本文选题：类普鲁士蓝 + 过渡金属　；参考：《南昌航空大学》2017年硕士论文

【摘要】：类普鲁士蓝(PBA)是人类很早就报道的一种有机配合物。其合成方法简便,比表面积大,孔径分布多样性,使得其在电催化产氧,钠离子电池和气体存储方面有着广泛的应用。但是其性能还是受导电性差和活性位点少限制。因此,我们以PBA为模板,通过不同的处理方式使得其衍生物具有更优异的电催化性能,主要工作如下:(1)我们提出了一种简便的阴离子交换法来合成氧掺杂的非晶硫化钴多孔纳米立方(A-CoS_(4.6)O_(0.6)PNCs)。阴离子交换反应使得材料形成具有大量缺陷位点的多孔结构。此外,A-CoS_(4.6)O_(0.6)PNCs更加趋向于形成更多的悬空键,同时将氧引入到CoS_x基质里面,大大增强了对氧的吸附能,使之能在较低的电压下驱动产氧反应的发生。在中性条件下,A-CoS_(4.6)O_(0.6)PNCs在1.8 V的电压下能达到4.59 m A cm~(-2)的电流密度,在碱性条件下,1.52 V的电压能够提供10mAcm~(-2)的电流密度。(2)我们通过在氩气中热解CoFe-PBA,得到了氮掺杂的碳包覆FeCo合金纳米粒子。在热解过程中,CoFe-PBA中的氰根离子同时提供碳源和氮源,形成氮掺杂碳,并且发生合金化反应生成Fe Co合金纳米粒子,得到核壳结构的纳米粒子(FeCo@NC)。根据一系列的电化学测试,实验合成的FeCo@NC能作为双功能催化剂能同时催化OER和ORR,在碱性条件下表现出良好的催化活性和稳定性:产氧起始电位1.45V,传递10 m A cm~(-2)的电流密度所需电压为1.49 V,塔菲尔斜率62 m V dec~(-1);氧还原起始电位0.94 V,半峰电位0.8 V。这些参数与贵金属基催化剂相当,使得它有可能应用于可再生能源装置中,特别是锌-空气电池。
[Abstract]:Prussian blue (PBA) is an organic complex that has been reported for a long time. The synthetic method is simple, with large specific surface area and diverse pore size distribution, which makes it widely used in electrocatalytic oxygen generation, sodium ion battery and gas storage. However, its performance is still limited by poor conductivity and few active sites. Therefore, we use PBA as a template to make its derivatives have better electrocatalytic performance through different treatment methods. The main work is as follows: 1) We have proposed a simple anion exchange method for the synthesis of oxygen-doped amorphous cobalt sulfide nanocrystalline cubic cuboid A-CoS _ S _ (4. 6) O _ (6) O _ (0.6) P _ (NCsS). The anion exchange reaction resulted in the formation of porous structures with a large number of defect sites. In addition, there is a tendency to form more suspending bonds in the structure of ACOS4.6ONCs. At the same time, oxygen is introduced into the CoS_x matrix, which greatly enhances the adsorption energy of oxygen and enables it to drive the occurrence of oxygen-producing reactions at a lower voltage. Under neutral conditions, the current density of PNCs can reach 4.59 Ma / cm ~ (-2) at a voltage of 1.8 V. The current density of 10mAcmAM-2V can be provided at 1.52V in alkaline condition.) by pyrolysis of CoFe-PBA in argon, nitrogen-doped carbon coated FeCo alloy nanoparticles are obtained. In the pyrolysis process, the cyanide ions in CoFe-PBA provide both carbon and nitrogen sources to form nitrogen-doped carbon, and the Fe-Co alloy nanoparticles are formed by alloying reaction. Based on a series of electrochemical tests, The synthesized FeCo@NC can be used as a bifunctional catalyst to catalyze OER and ORR simultaneously. It shows good catalytic activity and stability under alkaline conditions: the initial potential of oxygen production is 1.45 V, and the voltage required for the transfer of 10 Ma / cm ~ (-2) is 1.49 V, and the tower is a tower. The initial oxygen reduction potential was 0.94 V, and the half peak potential was 0.8 V. These parameters are similar to those of noble metal based catalysts, which make it possible to be used in renewable energy plants, especially in zinc-air batteries.
【学位授予单位】：南昌航空大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O643.36;O646

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