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 crucialfor building a high-efficiency biofuel cell for a more sustainable society andconstructing a sophisticated device to precisely detect trace amounts of glucosein blood and food for a more healthy life. Yet, the reported GOR catalysts sufferlow activity (current induced by catalysts toward 1 mM glucose in a 1 cm-2electrode,mu AmM-1cm-2), slow response, and poor response to trace glucose.Herein, we fabricate noble-metal-free WO3-decorated carbon nanotubes withstrong W-C bonds (WO3/CNT60) (CNT, carbon nanotube). In the GOR,WO3/CNT60 triggers an activity as high as 1960 mu AmM-1cm-2, a responsetime of only 3 s, and a response minimum of only 5 mu M and exhibitsoutstanding stability, anti-interference ability to impurities, and reusability. TheGOR performance of WO3/CNT60 is much better than the WO3/CNTcatalyst without W-C bonds (1320 mu AmM-1cm-2,10s,40 mu M) and the widely used noble-metal catalyst (270 mu AmM-1cm-2,10s, 25 mu M). The strong W-C bonds create more C-W-O-W bridge sites active for catalyzing the GOR, thus enhancing the GORperformance of WO3/CNT60. These results open a new way for fabricating a noble-metal-free high-efficiency biofuel cell andsophisticated device to precisely detect trace amounts of glucose and are also helpful for detecting and converting complex moleculeslike polyols and poly(carboxylic acid)s