Nitrogen‐doped Hollow Co₃O₄ Nanofibers for both Solid‐state pH Sensing and Improved Non‐enzymatic Glucose Sensing

Abstract

Abstract Nitrogen‐doped hollow cobalt oxide nanofibers (Co 3 O 4 NFs) with both glucose catalytic activity and pH sensitivity were fabricated through core‐sheath electrospinning technique, followed by calcination. The as‐developed nitrogen‐doped hollow Co 3 O 4 NFs were thoroughly characterized using various techniques, and then employed to fabricate a dual electrochemical sensor for both pH sensing and glucose sensing. The pH sensitivity of the developed nitrogen‐doped hollow Co 3 O 4 NFs demonstrated a Nernst constant of 12.9–15.9 mV/pH in the pH range of 3.0∼9.0 and 6.8–10.7 mV/pH in the pH range of 9.0∼13.0, respectively. The developed hollow cobalt oxides nanofibers sensor also possesses glucose sensitivity of 87.67 μA mM −1 cm −2 , the limit of detection of 0.38 μM (S/N=3), and an acceptable selectivity against several common interferents in non‐enzymatic glucose determination. High accuracy for monitoring glucose in human serum sample was also demonstrated. These features indicate that the as‐synthesized nitrogen‐doped hollow cobalt oxides nanofibers hold great potential in the development of a unique dual sensor for both solid‐state pH sensing and superior non‐enzymatic glucose sensing.