Stability enhancement of molybdenum modified rutile – carbon composite supported platinum electrocatalysts by reductive pretreatment: Surface characteristics and advanced electrocatalytic properties

Development of strong metal-support interaction (SMSI) and its influence on the catalytic performance of the Pt/Ti0.8Mo0.2O2-C system, a representative of the mixed oxide-carbon composite supported Pt electrocatalyst family, were investigated. Structural, surface chemical and electrochemical properties of the as-prepared Pt/Ti0.8Mo0.2O2-C catalyst and its counterparts reduced in the 150–450 °C temperature range were compared. TEM elemental mapping confirmed the widespread formation of Pt-oxide-C triple junctions in all catalysts. XPS revealed electronic interaction between the Pt particles and the oxide both in the as-prepared and the reduced catalysts, moreover, demonstrated that transport of Mo to the surface of Pt is initiated by reduction in the 150–250 °C range. Electrochemical measurements pointed out the durability of these Pt-bound Mo species, which also enhance the oxygen reduction activity of the catalyst. Based on the results of 10,000-cycle stability tests, reductive pretreatment between 250–350 °C is recommended for enhancing the properties of Pt/Ti0.8Mo0.2O2-C catalysts by SMSI.