Platinum Nanoparticles Encapsulated in Carbon Microspheres: Toward Electro-Catalyzing Glucose with High Activity and Stability

Electro-oxidizing glucose effectively is well known as the critical point in developing analytical sensors and carbohydrate-based fuel cells. Here we prepared a new electrode material, platinum nanoparticles encapsulated in carbon microspheres (Pt/GSH), to promote the glucose electrocatalytic oxidation reaction in neutral media. The Pt/GSH composite was synthesized by using a simple hydrothermal method, with reduced glutathione (R-GSH) as the capping agent and reductant simultaneously, followed by a calcination process. It was found that the obtained Pt particles with a mean size of 26.8 nm were well dispersed in the interconnected carbon microspheres, providing a stable and efficient catalytic platform for glucose electro-oxidation. As a result, the synthesized catalyst exhibited higher activity for electro-catalyzing glucose compared to commercial Pt black and Pt/C catalysts, with a mass activity of 15.4 mu A mu g(-1) Pt, approximately 13 times of Pt black and 2.1 times of Pt/C. Besides, due to the decreased dissolution and agglomeration of Pt NPs in the carbon-encapsulated structure, the Pt/GSH catalyst kept quite stable activity upon reuse even in the presence of chloride ions. (C) 2014 Elsevier Ltd. All rights reserved.