Facile controlled synthesis of AuPd and AuPt bimetallic nanocrystals for enhanced electrocatalytic sensing

The paper reported the controlled synthesis of dumbbell-style AuPd and dendrite-like AuPt by a simple seed-mediated growth method, respectively. The composition and performances of the resulting nanomaterials were measured using transmission electron microscopy (TEM), high-resolution TEM (HRTEM), UV-vis absorption spectroscopy (UV-vis), X-ray photoelectron spectroscopy (XPS) and electrochemical methods. Moreover, the dumbbell-style AuPd modified glassy carbon electrode (GCE) showed excellent electrocatalytic ability towards nitrite with a fairly wide concentration range from 2 mu M to 4200 mu M and a 0.67 mu M detection limit. The dendrite-like AuPt modified GCE showed excellent electrocatalytic ability towards tert-butyl hydroquinone (TBHQ) with a linear range from 0.35 mu M to 625 mu M and a relatively low detection limit of 0.075 mu M. The electrochemical testing results exhibited the two kinds of sensors, Au3Pd4/GCE and Au(3)pt(3)/GCE, possessed accepted selectivity, long-term stability and good reproducibility. Thus, the proposed two sensors could be applied in the determination of food samples. It is expected that the unique AuPd and AuPt are promising materials, which have great potential application in many fields of clinical diagnosis, new energy technologies, catalysis and sensors.