Facile water-based synthesis and catalytic properties of platinum–gold alloy nanocubes

Abstract

Controlled syntheses of noble metal based alloy nanocubes with {100} facets have attracted increasing attention due to their specific physical and chemical properties. This paper reports a facile, green and one-pot synthesis of platinum–gold alloy nanocubes (Pt–Au ANCs) with high yield and uniform size by a facile co-chemical reduction method. The detailed morphology, composition and structure of Pt–Au ANCs were fully characterized and their formation mechanism was investigated. The key synthesis strategy was the introduction of polyallylamine hydrochloride (PAH), which not only acted as a capping agent and facet-selective agent but also served as a complex-forming agent to effectively tune the reduction potentials of HAuCl₄/Au and H₂PtCl₆/Pt pairs to very close values. In addition, the as-prepared Pt–Au ANCs possessed excellent colloidal stability in aqueous solution and exhibited superior catalytic activity toward the reduction of 4-nitrophenol (4-NP) compared to commercial Pt black.