Synthesis of nonstoichiometric CeO2@CNT core/shell nanowire arrays and their applications in biosensing

•Nonstoichiometric CeO2@CNT nanowire arrays (NWAs) were synthesized.•Synergistic effect of nonstoichiometric CeO2 and CNT towards H2O2 detection was elucidated.•As-prepared NWAs were good substrate for the construction of cholesterol biosensors.

Nonstoichiometric CeO2@CNT core/shell nanowire arrays (NWAs) were synthesized by hydrothermal method in combination with chemical vapor deposition. Morphology and microstructure of the core/shell NWAs were characterized by SEM, XRD, TEM and Raman spectrum techniques. The novel nonstoichiometric CeO2@CNT core/shell NWAs were employed as substrates to construct cholesterol electrochemical biosensors. They showed high sensitivity of 336.6 μA cm−2 mM−1 and low detection limit of 7.4 µm towards cholesterol detection at working potential of −0.4 V due to synergistic effect of nonstoichiometric CeO2 and CNT, and they also demonstrated excellent selectivity towards interferents co-existing with cholesterol in blood serum.