Tuning structures of Pt shells on Pd nanocubes as neutral glucose oxidation catalysts and sensors

Nanocrystals with high-indexed facets and low-coordinated atoms exhibit promising electrocatalytic activities. Herein, different Pt shell structures on the surface of Pd nanocubes (Pd@Pt NCs) were synthesised by varying the concentration of Pt precursors. The concave Pd@Pt NCs were used as electrocatalysts for neutral glucose oxidation reactions (GORs); the effect of Pt structure on the catalytic performance was studied. In sequential catalysis, stellated Pd@Pt NCs (Pd@Pt SNC) with (211) facets had an electron transfer number (Ne) of 12.69 and a specific activity of 4.69 x 10(-9) mol.g.m(-2), markedly higher than that of the other concave Pd@Pt NCs. In transient catalysis, Pd NCs with Pt-coated corners (Pd@Pt CNCC) containing (210) and (950) facets demon-strated a sensitivity of 11.06 mu A.mM(-1).cm(-2) and a linear analysis range (2.4-10.6 mM). The high recoveries (98.80%-99.85%) and low relative standards (<= 1.06%) in the serum sample corroborate the potential of Pd@Pt CNCC as an enzyme-free glucose sensor.

Automated summary

This paper investigates the application of nanocrystals with high-indexed facets in electrocatalysis. Different Pt shell structures were synthesized on the surface of Pd nanocubes by varying the concentration of Pt precursors, and their catalytic performances were studied. The results demonstrate that nanocrystals with specific facet structures exhibit higher catalytic activity and sensitivity, showing potential as glucose sensors.