WO3 supported PtRu nanoalloys with tunable composition for enhancing catalytic activity

Abstract

Creating a rational metal/metal oxide heterojunction represents an effective way to boost catalytic activity. Here, WO3/PtRu hybrid nanostructures were fabricated by depositing dendrite PtRu nanoalloys with tunable composition on WO3 nanosheets using the chemical reduction method. The WO3/PtRu hybrid nanostructures were characterized and investigated comprehensively for their multiple catalytic activities. Due to the strong metal-support interaction (SMSI) effect, WO3 nanosheets played critical roles in supporting PtRu nanoalloys with more active surface and facilitating electronic charge transfer, which can be used as active support to PtRu nanoalloys. As a result, WO3/Pt3Ru1 exhibits significantly higher catalytic activity than Pt3Ru1 to varying degrees for various catalytic reactions, including the oxidation of Fe2+ and the decomposition of H2O2, exhibiting enhanced oxidase-like (ferroxidase) and catalase-like activity, and reduction of 4-Nitrophenol (4-NP) in presence of NaBH4 and scavenging of DPPH free radicals. Furthermore, the activity is relied on the composition of PtRu nanoalloys but in distinct manner. The oxidase-like, catalase-like and DPPH scavenging activities showed similar order of WO3/Pt3Ru1 > Pt3Ru1 > WO3/Pt1Ru1 > WO3/Pt1Ru3, while 4-NP reduction activity order is WO3/Pt1Ru3 > WO3/Pt1Ru1 > Pt3Ru1 > WO3/Pt3Ru1. These results will be of value for efficient design of hybrid nanostructures with high performance and multiple functions.