本文基于NiO作为Pt催化甲醇助催化剂的思路,通过Pt纳米颗粒担载在NiO修饰的碳材料载体上制备了Pt/NiO-C催化剂,系统地研究了不同的NiO/C热处理温度对Pt粒径的影响,并重点探讨了Pt对NiO的质量比对催化氧化甲醇的影响.X射线衍射分析结果显示NiO和Pt均为立方晶系,且NiO的加入有利于主催化剂Pt形成较小的粒径,且经400℃热处理NiO修饰的C材料作为载体有利于Pt的有效分散.所获得的Pt/NiO-C催化剂的电化学活性在甲醇酸性溶液中通过循环伏安法(CV)和计时电流法(CA)进行性能测试.CV测试结果显示以Pt/NiO重量比为4∶1的催化剂其电氧化甲醇活性最大,其峰值氧化电流密度达806 mA/mgPt,是Pt/C催化剂的1.64倍.CA测试结果显示Pt/NiO-C比Pt/C具有更好的抗CO中毒性能和稳定性.%In an attempt to utilize NiO as a co-catalyst with Pt for methanol electro-oxidation,Pt/NiO-C were prepared by attaching Pt nanoparticles on NiO coated Vulcan XC-72R carbon blacks in this study. Heat treatment of NiO at different temperatures on the influences of Pt particle size was investigated,and the weight ratio of Pt to NiO on the catalytic oxidation of methanol was also studied. X-ray diffraction results indicated that both NiO and Pt belong to cubic structure and Pt nano-particles on NiO/C supports had smaller particle size than those on Vulcan XC-72R without NiO. NiO/C heat treatment at 400℃ is good for Pt effective dispersion. The methanol electro-oxidation was studied in acid medium by cyclic voltammetry and chronoamperometry. The catalytic activity of Pt for methanol oxidation can be significantly enhanced by introducing NiO. The composition with ratio of Pt to NiO(4:l)exhibited the highest mass activity(806 mA/mgp,)in the as-prepared version,which was 1. 64 times higher that that on the Pt/C catalyst. Pt/NiO-C catalysts showed better stability and CO tolerant capability than Pt/C catalysts from chronoamperometry testing.
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