Co₃O₄ based non-enzymatic glucose sensor with high sensitivity and reliable stability derived from hollow...

Inspired by kinetics, the design of hollow hierarchical electrocatalysts through large-scale integration of building blocks is recognized as an effective approach to the achievement of superior electrocatalytic performance. In this work, a hollow, hierarchical Co₃O₄ architecture (Co₃O₄ HHA) was constructed using a coordinated etching and precipitation (CEP) method followed by calcination. The resulting Co₃O₄ HHA electrode exhibited excellent electrocatalytic activity in terms of high sensitivity (839.3 μA mM^-1 cm^-2) and reliable stability in glucose detection. The high sensitivity could be attributed to the large specific surface area (SSA), ample unimpeded penetration diffusion paths and high electron transfer rate originating from the unique two-dimensional (2D) sheet-like character and hollow porous architecture. The hollow hierarchical structure also affords sufficient interspace for accommodation of volume change and structural strain, resulting in enhanced stability. The results indicate that Co₃O₄ HHA could have potential for application in the design of non-enzymatic glucose sensors, and that the construction of hollow hierarchical architecture provides an efficient way to design highly active, stable electrocatalysts.