Oxygen vacancies enriched multi-channel-like metal-doped Co3O4 nanosheets by Lewis acid etching for detection of small biological molecules in apple juice and wine

Excessive small biological molecules such as Cd(II), Pb(II) and glucose in food pose a non-negligible threat to its inherent quality and human health, which makes it imperative to develop the highly sensitive sensor for Cd(II), Pb(II) and glucose detection. Metal cation-doped Co3O4 modified electrode materials have attracted vital interest in the electrochemical detection of Cd(II), Pb(II) and glucose because of their synergetic effect on Cu/Co and oxygen vacancies. Herein, a simple morphology and defect modulation strategy is proposed to synthesize multi-channel-like M-doped Co3O4 nanosheets (M = Cu, Mn, Fe, Ni, and Zn) via the Lewis acid etching process. The Cu/Co interaction and oxygen vacancies of Cu-Co3O4 multichannel nanosheets play an important role in the simultaneous detection of small biological molecules. The Cu-Co3O4 multichannel nanosheets exhibit the sensitivity of 20.59 µA µM−1 for Pb(II), 8.73 µA µM−1 for Cd(II) as well as 1613.86 µA mM−1 cm−2 for glucose, which is successfully applied in food applications such as apple juice and wine and maintain excellent stability and anti-interference. This design not only successfully constructs oxygen vacancies enriched M-Co3O4 multichannel nanosheets, but also demonstrates the application potential of electrochemical sensors in food safety.