Noble-Metal-Free WO3-Decorated Carbon Nanotubes with Strong W–C Bonds for Boosting an Electrocatalytic Glucose Oxidation Reaction

An electrocatalytic glucose oxidation reaction (GOR) is crucial for building a high-efficiency biofuel cell for a more sustainable society and constructing a sophisticated device to precisely detect trace amounts of glucose in blood and food for a more healthy life. Yet, the reported GOR catalysts suffer low activity (current induced by catalysts toward 1 mM glucose in a 1 cm–2 electrode, μA mM–1 cm–2), slow response, and poor response to trace glucose. Herein, we fabricate noble-metal-free WO3-decorated carbon nanotubes with strong W–C bonds (WO3/CNT60) (CNT, carbon nanotube). In the GOR, WO3/CNT60 triggers an activity as high as 1960 μA mM–1 cm–2, a response time of only 3 s, and a response minimum of only 5 μM and exhibits outstanding stability, anti-interference ability to impurities, and reusability. The GOR performance of WO3/CNT60 is much better than the WO3/CNT catalyst without W–C bonds (1320 μA mM–1 cm–2, 10 s, 40 μM) and the widely used noble-metal catalyst (270 μA mM–1 cm–2, 10 s, 25 μM). The strong W–C bonds create more C–W–O–W bridge sites active for catalyzing the GOR, thus enhancing the GOR performance of WO3/CNT60. These results open a new way for fabricating a noble-metal-free high-efficiency biofuel cell and sophisticated device to precisely detect trace amounts of glucose and are also helpful for detecting and converting complex molecules like polyols and poly(carboxylic acid)s.