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硼氢化物水解是导致直接硼氢化物燃料电池(DBFC)燃料效率下降的主要问题之一.将Co3O4用于DBFC阳极催化剂并通过镀银处理以降低水解反应.以CoCl2·6H2O为原料制备Co3O4,并通过银镜反应对其进行镀银处理,制得Co3O4@Ag.通过X射线衍射(XRD)、扫描电子显微镜(SEM)和能谱(EDS)对其进行物理表征,通过交流阻抗(EIS)、计时电流(CA)和电池测试对其电化学性能进行表征.结果表明,利用银镜反应成功地将Ag引入到催化剂体系,且Co3O4@Ag催化材料的含银量为2%.电化学测试表明,与Co3O4相比Co3O4@Ag具有更高的电催化活性.以Co3O4@Ag为阳极催化剂组装的燃料电池在室温下最大功率密度(55 mW·cm-2)和比容量(971 mA·h·g-1)较Co3O4分别提高了44.7%和32.1%,阳极催化剂性能得到显著提高.Ag在抑制水解反应的同时与Co3O4体现了协同催化的作用.“,”Hydrolysis of borohydride is one of the major problems leading to a decrease in the fuel efficiency of direct borohydride fuel cell (DBFC). Co3O4was first used as DBFC anode catalyst and to reduce the hydrolysis reaction by silver plating treatment. Co3O4was prepared by using CoCl2·6H2O and silvered on its surface by silver mirror reaction to obtain Co3O4@Ag. The physics properties of the catalyst were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS). The electrochemical properties were investigated by electrochemical impedance spectroscopy (EIS), chronoamperometry (CA) and fuel cell test. The characterizations demonstrate that Ag was successfully introduced into the catalyst system by silver mirror reaction and account for 2% of the Co3O4@Ag catalytic material. Electrochemical tests showed that Co3O4@Ag had a higher electro-catalytic activity than Co3O4. The maximum power density (55 mW·cm-2) and specific capacity (971 mA·h·g-1) of fuel cell, which was fabricated by using Co3O4@Ag as anode catalyst, increased by 44.7% and 32.1%, respectively than Co3O4 at room temperature. The performance of anode catalyst was significantly increased. Ag reflected the synergistic catalytic effect with Co3O4 when it inhibited the hydrolysis reaction.