用Pt/C催化剂通过浸渍-还原法制备疏水催化剂

选择XC-72R炭黑为载体,采用改进的浸渍-还原法制备了2~3 nm高分散度Pt/C催化剂。研究了还原温度、还原剂、pH和甲醛用量等工艺条件对Pt粒径大小及分散度的影响,采用透射电镜和X射线衍射等对催化剂进行表征。结果表明,提高溶液pH和反应温度、增加甲醛用量均有助于得到Pt粒子粒径较小的高分散度Pt/C催化剂,较佳的工艺条件为:用乙二醇与水为炭黑分散溶剂,反应温度80~90℃,pH≈11,甲醛用量80倍于PtCl62-物质的量,可以制备Pt粒子粒径在2 nm左右的高分散度Pt/C催化剂。

Preparation of Pt/C catalysts for hydrophobic catalyst by impregnation and reduction method

Carbon supported platinum catalysts about 2~3 nm in size have been prepared by improved impregnation-reduction method,XC-72R carbon black selected as carrier for platinum.The investigated conditions includes the reduction temperature,the reducing agents,pH,and the dosage of formaldehyde.TEM and XRD images show that higher pH value,reaction temperature,and HCHO dosage are favorable for the fabrication of high-dispersed Pt/C catalysts,and Pt nanoparticles size can be controlled by changing these conditions.The preferable preparation method is that using mixed solvent of glycol and H2O as disperse solvent,the reduction temperature controlled from 80 ℃ to 90 ℃,pH around at 11,and the dosage of formaldehyde 80 times much as that of PtCl2-6,platinum nanoparticles about 2 nm in size and good dispersity on carbon surfaces will be prepared.