Pt/MoC的制备及其在电解水析氢反应中的催化性能
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摘要
以钼酸铵和氯铂酸为原料,通过原位程序升温碳化过程,合成了Pt负载量不同的Pt/MoxCy(x∶y≤2)催化剂,并考察了其在电解水析氢反应(HER)中的催化性能。利用XRD、BET、SEM、TEM、XPS对催化剂的微观结构及物理化学性质进行了表征。结果表明,Pt的负载改变了碳化钼形成的拓扑结构,Pt负载后的样品更容易形成α-Mo_2C相。Pt的负载量对碳化钼催化剂在HER反应中的催化性能具有显著影响,1.6Pt/MoC[n(Pt)∶n(Mo)=1.6∶98.4]催化剂表现出最优催化效果(过电势ηonset=108m V,塔菲尔斜率b=74m V/dec)及较低的阻抗(18.77?),可以与商业Pt/C催化剂相媲美。
Pt/Mo_xC_y(x∶y≤2) catalysts with different Pt loadings were synthesized using ammonium molybdate and chloroplatinic acid as raw materials through in situ temperature-programmed carbonization process and their catalytic activities in the hydrogen evolution reaction(HER) of electrolyzed water were investigated. Their microstructure and physicochemical properties were characterized by XRD, BET, SEM, TEM and XPS. The results showed that the introduction of Pt changed the topological structure of molybdenum carbide during the carbonization process and made the prepared samples easier to form the α-Mo_2C phase. The loading of Pt had a significant effect on the catalytic activity of molybdenum carbide catalyst in the HER reaction. Among the samples, the 1.6 Pt/MoC [n(Pt) ∶n(Mo)=1.6∶98.4]catalyst exhibited the best catalytic activity(overpotential ηonset=108 mV, Tafel slope b=74 mV/dec) and had lower impedance(18.77 ?), which could be comparable with the commercial Pt/C catalyst.
Pt/Mo_xC_y(x∶y≤2) catalysts with different Pt loadings were synthesized using ammonium molybdate and chloroplatinic acid as raw materials through in situ temperature-programmed carbonization process and their catalytic activities in the hydrogen evolution reaction(HER) of electrolyzed water were investigated. Their microstructure and physicochemical properties were characterized by XRD, BET, SEM, TEM and XPS. The results showed that the introduction of Pt changed the topological structure of molybdenum carbide during the carbonization process and made the prepared samples easier to form the α-Mo_2C phase. The loading of Pt had a significant effect on the catalytic activity of molybdenum carbide catalyst in the HER reaction. Among the samples, the 1.6 Pt/MoC [n(Pt) ∶n(Mo)=1.6∶98.4]catalyst exhibited the best catalytic activity(overpotential ηonset=108 mV, Tafel slope b=74 mV/dec) and had lower impedance(18.77 ?), which could be comparable with the commercial Pt/C catalyst.
引文
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[11]Bouchy C,Schmidt I,Anderson J,et al.Metastable fccα-MoC1-x supported on HZSM5:preparation and catalytic performance for the non-oxidativeconversion of methane to aromatic compounds[J].Journal of Molecular Catalysis A Chemical,2000,163(1):283-296.
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