Synthesis of Surface Roughed Pt Nanowires and Their Application as Electrochemical Sensors for Hydrogen Peroxide Detection

Abstract

In this paper, platinum nanowires with roughed surface textures were fabricated by a galvanostatic electrodeposition method for electrochemical sensors toward hydrogen peroxide detection. The electrochemical behavior of the glassy carbon electrode modified with these nanowires has been studied for oxidation of hydrogen peroxide by using cyclic voltammetry and amperometry in phosphate buffer solution. Surface roughness was found to enhance the sensitivity of the Pt nanowire based electrochemical sensor towards H2O2. The Pt nanowires with rough surfaces displayed higher electrocatalytic response compared to nanowires with smooth surfaces, with a sensitivity of 171 μA mM(-1) cm(-2), and linear dynamic range up to 35 mM. The nanowire concentration effect on the sensing behavior was investigated with the best sensitivity output found at a nanowire concentration of roughly 8.6 x 10(7) number of nanowires/cm2. The new sensor also showed good anti-interference property and exhibited high accuracy when a real water sample containing H2O2 was measured.

Effects of Nanowire Length and Surface Roughness on the Electrochemical Sensor Properties of Nafion-Free, Vertically Aligned Pt Nanowire Array Electrodes

“…Figure 2 B presents the rough surface Pt nanowires deposited at high current density, and a number of large grains can be found which are consistent with the SEM images as shown in Figure 1 B. As shown in Figure 2 B, large grain size can be observed in the surface rough nanowires, which compares well with our previous publications [ 41 , 42 ].…”

“…The bonding between the nanowires and the substrate is still strong enough to hold the nanowires, however, unable to keep them completely vertical. The rough surface Pt nanowires ( Figure 1 B,D,F), as shown in our previous researches [ 41 , 42 ], are believed to be due to larger grain sizes formed in the nanowires during the electrodeposition procedure [ 41 ]. For instance, Figure 1 A,C,E show the smooth surface of the PtNWA prepared at low current density (1.5 mA·cm −2 ) with different deposition times, indicating that small nuclei were formed and these small nuclei packed the whole pore area of the AAO template very well, thus the surface of the nanowires looks smooth and uniform.…”

“…The sensitivity of 12 μm rough surface PtNWA is the highest due to its largest electroactive surface area (see Figure 7 A). The sensitivity of short (3 μm) smooth PtNWA is almost identical to the 4 μm rough PtNW modified GCE, but higher than the 4 μm smooth one [ 42 ]. The short (3 μm) rough PtNWA electrode presented a better sensitivity than a 4 μm smooth/rough PtNW modified GCE electrode, which means the well-ordered vertically standing structure can indeed enhance the electrochemical properties.…”

“…The PtNWA electrodes were fabricated by electrodeposition in the AAO membrane [ 41 , 42 , 43 ] as shown in Scheme 1. First, one side of the AAO membrane was coated with a 200 nm thick Ag layer in a CHA 6 Pocket Electron Beam Evaporator (CHA’s Solution™ Process Development System, Fremont, CA, USA) at the rate of 0.1 nm·s −1 .…”

“…Due to their high aspect ratio and unique surface properties, nanowires possess excellent electrochemical and catalytic performance. Among various nanomaterials, platinum (Pt) is one of the most studied noble metals in the sensor and catalyst fields [ 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 ]. Pt nanowire-based sensors have many applications, especially in the detection of H 2 O 2 , which is attributable to the fact that the decomposition of hydrogen peroxide into water and oxygen can be effectively catalyzed by Pt.…”