Epoxy-sealed single Pt nanoelectrodes: Fabrication and electrocatalytic performance for the methanol oxidation reaction

Epoxy-sealed single Pt nanoelectrodes (SPNEs) ranging in size from 3 to 300 nm have been fabricated by a laser-assisted pulling method and characterized by optical microscopy, transmission electron microscopy (TEM) and electrochemical methods. The prepared SPNEs were used to investigate the methanol oxidation reaction (MOR), and the results show that the electrocatalytic activity of the SPNEs towards MOR depends on the radius of the electrode. In the range of electrode radii tested (3 nm-280 nm), the electrocatalytic activity decreases if the radius of the SPNE is either too small or too large, with optimal electrocatalytic efficiency being observed when the radius is about 4.2 nm.