Facile fabrication of network film electrodes with ultrathin Au nanowires for nonenzymatic glucose sensing and glucose/O2 fuel cell

•Ultrathin Au nanowires (AuNWs) with an average diameter of 2 nm were prepared.•AuNWs can self-assemble into robust network films on common electrodes.•The network film electrode possesses high electroactive surface area and specific electroactive surface area.•The network film electrode exhibits high electrocatalytic activity toward glucose oxidation under physiological conditions.•The network film electrode can be used for high-performance glucose sensing and glucose/O2 fuel cell.

We report here on the facile fabrication of network film electrodes with ultrathin Au nanowires (AuNWs) and their electrochemical applications for high-performance nonenzymatic glucose sensing and glucose/O2 fuel cell under physiological conditions (pH 7.4, containing 0.15 M Cl−). AuNWs with an average diameter of ~7 or 2 nm were prepared and can self-assemble into robust network films on common electrodes. The network film electrode fabricated with 2-nm AuNWs exhibits high sensitivity (56.0 μA cm−2 mM−1), low detection limit (20 μM), short response time (within 10 s), excellent selectivity, and good storage stability for nonenzymatic glucose sensing. Glucose/O2 fuel cells were constructed using network film electrodes as the anode and commercial Pt/C catalyst modified glassy carbon electrode as cathode. The glucose/O2 fuel cell using 2-nm AuNWs as anode catalyst output a maximum power density of is 126 μW cm−2, an open-circuit cell voltage of 0.425 V, and a short-circuit current density of 1.34 mA cm−2, respectively. Due to the higher specific electroactive surface area of 2-nm AuNWs, the network film electrode fabricated with 2-nm AuNWs exhibited higher electrocatalytic activity toward glucose oxidation than the network film electrode fabricated with 7-nm AuNWs. The network film electrode exhibits high electrocatalytic activity toward glucose oxidation under physiological conditions, which is helpful for constructing implantable electronic devices.