Pt电极表面有机小分子毒化中间体CO覆盖度的有效调控

发布时间：2018-03-25 05:12

本文选题：甲醛　切入点：高效流动电解池　出处：《中国科学:化学》2017年05期

【摘要】：燃料电池因高能量利用率和环境友好等优点成为最有发展前途的一种能量利用方式,但有机小分子中间产物(CO)导致催化剂中毒一直是困扰燃料电池阳极催化剂的重要问题.本文利用可控电位高效更换溶液的电解池研究了不同电位下甲醛(HCHO)在Pt电极上解离CO的过程.实验结果表明,随着电位正移,HCHO在Pt上产生的CO覆盖度由.0.2 V的71%逐渐下降到0.25 V的60%.0.3 V起覆盖度急剧下降,在0.35 V时控电位的覆盖度仅有8%,远小于开路电位(ocp)下的64%.这预示着可以利用CO覆盖度的区别,提出一种新的电极操作方法以降低CO对电极的毒化.HCHO验证实验表明,控电位0.35 V时加入甲醛稳定300 s后,起始氧化电流为3×10~(-4 )A,接近峰值电流4×10~(-4) A,远大于ocp实验的3×10~(-5) A.控制工作电极电位0.35 V时加入甲醛,有效地降低了CO毒化对电极的影响
[Abstract]:Fuel cells have become one of the most promising energy utilization methods due to their high energy utilization efficiency and environmental friendliness. However, the poisoning of catalyst caused by organic small molecule intermediate product (COO) has always been an important problem for fuel cell anode catalyst. In this paper, the electrolysis cell with controllable potential to change solution efficiently was used to study HCHO-formaldehyde in Pt electrolysis at different potential. The process of dissociation of CO on the pole. The experimental results show that, The CO coverage of HCHO on Pt decreased gradually from 71% of 0.2V to 60.0.3V at 0.25 V with positive potential shift. At 0.35 V, the coverage of the controlled potential is only 8%, which is much smaller than that under the open circuit potential (OCP). This indicates that the difference of CO coverage can be utilized. A new electrode operation method is proposed to reduce the toxicity of CO to the electrode. The initial oxidation current is 3 脳 10 ~ (-4) A, which is close to the peak current of 4 脳 10 ~ (-4) A, which is much larger than that of 3 脳 10 ~ (10 ~ (-5)) A in ocp experiment. The effect of CO poisoning on the electrode can be effectively reduced by adding formaldehyde at 0.35V of controlled potential.
【作者单位】：泉州师范学院化工与材料学院;
【基金】：教育部新世纪优秀人才计划(编号:NCET-13-0879) 福建省闽江学者特聘教授计划泉州市桐江学者特聘教授计划福建省自然科学基金(编号:2016J01069)资助项目
【分类号】：O643.36;TM911.4

【相似文献】