Shape-Controlled Gold Nanoarchitectures: Synthesis, Superhydrophobicity, and Electrocatalytic Properties
A simple one-step electrodeposition method was used to fabricate various gold nanostructures on glassy carbon electrodes in a low concentration of HAuCl4 solution (5 mM). The morphologies of final gold nanostructures can be easily controlled by varying the pH of the precursors or the deposition temperature. X-ray powder diffraction, scanning electronic microscopy, transmission electron microscopy, contact angle measurements, and electrochemical methods were used to characterize them. Hierarchical waxberry-like gold nanostructures with high active surface areas were obtained in pH 4 bath, and they had a higher catalytic performance for the reduction of oxygen than the other nanogold. These gold structures also displayed an extraordinary superhydrophobicity and the contact angle increased with the increase of deposition temperature and time. Their electrocatalytic response to the oxidation of glucose was also investigated. A sensitive enzyme-free sensor can be easily developed for the detection of glucose in pH 7.4 phosphate buffer solution.