摘要
采用胶体法分别以乙酰丙酮铂(Pt(acac)_2)和乙酸镍(Ni(ac)_2·4H_2O)为前驱体制备了(1:3,1:1,3:1)不同摩尔比的Pt-Ni合金纳米粒子,将其负载在XC-72碳黑载体获得Pt-Ni/C双金属催化剂,其中Pt_3Ni/C催化剂催化活性最高,其正向扫描峰电流密度是42.5 m A·cm^(-2),分别是Pt Ni/C、Pt Ni3/C和Pt/C催化剂的3.2、5.3和1.2倍;而催化剂抗中毒能力则是Pt Ni_3/C最强(I f/I b值为23.5)。TEM和XRD分析表明Pt-Ni双金属纳米粒子单分散性好,粒径分布为2~4nm;同时XPS结果表明Ni的掺杂改变了Pt的外层电子层结构,减少了表面Pt原子对CO的吸附,释放出更多的Pt活性位,从而提高了Pt-Ni/C双金属催化剂的电催化活性和抗中毒能力。
Pt-Ni alloy nanoparticles with different atomic ratios of Pt to Ni （1：3;1：1;3：1） were prepared by colloidal synthesis method with Pt（acac）2 and Ni（ac）2？4H2O as precursors, respectively, and Pt-Ni/C bi-metallic catalysts were obtained after the nanoparticles were loaded on the surface of XC-72 carbon supports, and Pt3Ni/C catalysts displayed the best catalytic activity. The peak current density of Pt3Ni/C catalyst was 42.5 mA.cm-2 at the positive scanning, which was 3.2, 5.3 and 1.2 times as high as those of PtNi/C, PtNi3/C and Pt/C catalysts, and else the anti-poisoning ability of PtNi3/C was the strongest （If/Ib was 23.5） contorted with other samplers. TEM and XRD analysis indicated that Pt-Ni bi-metallic nanoparticles are uniformly distributed with the sizes ranging from 2 to 4 nm, and XPS demonstrated that the addition of Ni changes the external electronic structure of Pt, reduces the absorption of CO on Pt and releases more Pt active sites, which was the reason for the electrocatalytic activity and anti-poisoning ability of Pt-Ni/C catalyst improved.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2016年第10期2697-2702,共6页
Rare Metal Materials and Engineering
基金
国家表面偏析和电化学法调控低铂纳米催化剂核壳精细结构及催化性能研究项目(51374117)
关键词
胶体合成法
Pt-Ni/C双金属催化剂
甲醇氧化
电催化性能
colloidal synthesis method
Pt-Ni/C bi-metallic catalyst
methanol oxidation
electrocatalytic properties
