Microstructure and electrocatalytic performance of nanoporous gold foils decorated by TiO2 coatings

•An amorphous TiO2 coating was sputtered on nanoporous gold (NPG) foils.•Microstructure and electrocatalytic performance of TiO2@NPG are studied.•The TiO2 coatings cover the Au ligaments and retain the porous structure.•The electrocatalytic performance of TiO2@NPG toward glucose is improved.•The TiO2@NPG structure produces a synergistic effect between TiO2 and Au.

An ultra-thin TiO2 coating was sputtered onto the surface of nanoporous gold (NPG) foil by magnetron sputtering. The microstructure of the TiO2@NPG was studied by scanning electron microscopy, transmission electron microscopy, atomic force microscopy and X-ray photoelectric spectroscopy. The TiO2 coating, characterized by an amorphous structure, covers the Au ligaments, increases the ligament size and decreases the surface roughness. The electrocatalytic activities of TiO2@NPG toward the glucose oxidation in alkaline media were measured by cyclic voltammetry method. The experimental results exhibit that the TiO2@NPG composites present an obvious improvement of electrocatalytic performance compared with the bare NPG. The effect of TiO2 content on the electrocatalytic performance is investigated, and a synergistic effect between TiO2 and NPG is discussed.

Graphical abstractTEM image of the TiO2@NPG-20 foil. The FFT patterns on the lower-right and upper-left are corresponding to the Zone 1 and Zone 2, respectively. The inset on the upper-right is the inverse FFT of the Zone 2.Figure optionsDownload full-size imageDownload high-quality image (186 K)Download as PowerPoint slide