Glucose is a vital monosaccharide for catabolism, but
its imbalances
can lead to diabetes, a chronic disease without a cure but manageable
through diet and lifestyle changes. For people with diabetes, timely
monitoring of glucose level is very important for treatment. This
can be done by various glucose sensors. However, the rational design
and controllable synthesis of glucose catalysts with low-cost and
high-efficiency glucose detection ability are still challenging. Herein,
copper selenide micro/nanocrystal-modified carbon paper (Cu2–xSe/CP) self-supporting electrodes were prepared by
a facile electrodeposition method followed by chemical vapor deposition.
The rod-shaped carbon substrate and shale-shaped Cu2–xSe micro/nanoparticles resulted in the formation
of a hierarchical structure. The synergistic effects between Cu2–xSe active sites and carbon paper
promoted electronic transfer, resulting in an enhanced electrocatalytic
performance for glucose oxidation. The optimized Cu2–xSe/CP exhibited excellent glucose sensing performance
with linear detection ranges of 5–200 and 200–760 μM,
as well as high sensitivities of 5391 μA mM–1 cm–2 at low glucose concentrations and 3004 μA
mM–1 cm–2 at high concentrations
with a low detection limit of 1.2 μM (S/N = 3). In addition,
Cu2–xSe/CP exhibited excellent
reproducibility, stability, anti-interference, and long-term storage
ability. The practical applications of Cu2–xSe/CP were evaluated by measuring glucose in real human serum
samples and artificial saliva, and the results displayed an outstanding
performance. In sum, the proposed Cu2–xSe/CP-modified electrode with excellent glucose electrocatalytic
activity is very promising for future clinical non-enzymatic glucose
detection.