PNNL

Abstract

Metallic hydrogels/aerogels are receiving tremendous attentions due to their featured three dimensional (3D) hybrid pore systems and superior electrocatalytic performances. The bimetallic Au/Pt hydrogel formed from gold and platinum sol has not yet been successfully obtained till now. Here, for the first time, we reported two effective strategies of kinetically synthesis of AuPt metallic hydrogels. The first one takes 2-4 hrs via increasing the reaction temperature to 60 °C without any surfactant. The second one takes 1-2 hrs via addition of dopamine at room temperature. Both of these two methods facilitate the orientated attachment of nanoclusters and short nanowires. The as-prepared 3D AuPt aerogels are composed of interconnected ultrathin nanowires with diameter of about 3-6 nm. Besides, much more non-nobles elements (i.e. Fe, Co, Ni, Pb, Cu etc.) were introduced to metallic aerogels. The as-attained surfactant-free AuPt5 metallic aerogels displayed enhanced electrocatalytic activities and stabilities toward methanol oxidation compared commercial Pt/C. The successful and efficient synthesis of Au-Pt metallic aerogels and the addition of non-noble metals fills the vacancy of metallic aerogels. The as-obtained AuPt5 metallic aerogels with superior catalytic performances, showed a great opportunity for mass production of self-supported electrocatalysts for fuel cells and other devices.