乙二醇稳定的Pt/C催化剂的制备与表征

以乙二醇(EG)兼作溶剂和稳定剂,分别通过NaBH4和EG还原法制备了高度细化与分散的Pt/C催化剂,对其形貌、组成、结构和电化学活性比表面等进行了表征比较,并测试了它们对甲醇与乙醇电催化氧化的活性. 结果表明,2种催化剂中,Pt均为面心立方结构,粒径小且分布窄,在炭黑载体上分散均匀,单位质量Pt对甲醇与乙醇电催化氧化的活性相当;NaBH4还原法所制Pt/C催化剂中Pt0和Pt(220)晶面含量更高,Pt对甲醇与乙醇电催化氧化的峰电流密度分别为0.68与0.67 mA/cm2,分别是EG还原法所制Pt/C催化剂的1.2倍;2种催化剂对甲醇与乙醇电催化氧化的活性均与商品E-TEK催化剂相当.

Preparation and Characterization of Pt/C Catalysts Stabilized by Ethylene Glycol

Pt/C catalysts with narrow size distribution and high dispersion were prepared by NaBH_4 and ethylene glycol (EG) reduction methods, separately, using EG as both the solvent and stabilizing agent. Their morphology, composition, structure and electrochemically active specific surface area (ECSA) were characterized and compared. Electrocatalytic activities of the two catalysts for oxidation of methanol or ethanol were tested. The two catalysts present narrow size distribution, high dispersion, face centred cubic structure of Pt, and comparative Pt-mass based activities for electro-oxidation of methanol and ethanol. The Pt/C catalyst prepared by NaBH_4 reduction method has more metallic Pt (Pt~0) and more crystal face Pt (220), its Pt electrochemical surface area (Pt ECAS) based anodic peak current densities for methanol and ethanol oxidations are 0.68 and 0.67 mA/cm~2, 1.2 times higher than those of the Pt/C catalyst prepared by EG reduction method, respectively. Their electrocatalytic activities for methanol and ethanol are comparable with those of commercial E-TEK catalysts.