Silver nanoplates: Tetradecyltrimethylammonium ions as additives in seed-growth synthesis and their potential application as catalysts for glucose oxidation reaction

Tetradecyltrimethyl ammonium ions (C(14)TA(+)) were used as trace additives in a seed solution to block the (1 1 1) seed surface so as to govern the growth direction and pathway, leading to the formation of Ag nanoplates. The spectra of the obtained nanoplate solution showed a high intensity peak, attributed to the in-plane dipole resonance, and a low-intensity peak at 400 nm. By decreasing the amount of C(14)TA(+)-adsorbed seed amount from 20 mu L to 15 mu L and 5 mu L the mean height of triangular nanoplates was altered from similar to 96 nm to similar to 130 nm and similar to 177 nm. The in-plane dipole resonance peak, which corresponds to the change in the mean height, shifted from 655 nm to 740 nm and 807 nm, respectively. To investigate the feasibility of practical application of the proposed method, the prepared nanoplates were used as an electrocatalyst to sense a glucose oxidation reaction (GOR). A cyclic voltammogram of the nanoplates showed two significant peaks during the cathodic sweep, indicating that the anodic oxides provide active sites and have high GOR activity. Simultaneously, the results measured by potential deposition of Pb show the nanoplates have electrochemical surface areas (ESAs) of 96 nm > 130 nm > 177 nm. The higher activity on the 96 nm sized nanoplates is attributed to the fact they have the largest ESA. Remarkably, the prepared nanoplates show high potential as glucose sensors, in that the 96 nm nanoplates showed 0.527 mA mM(-1) cm(-2) sensitivity for glucose. (C) 2013 Elsevier Ltd. All rights reserved.