A highly efficient and selective magnetic CoFe2O4@covalent organic framework nanozyme for electrochemical sensors

Metal oxide nanozymes are widely used in biosensors but face challenges such as weak selectivity, low efficiency and poor stability. In this work, magnetic CoFe 2 O 4 @covalent organic frameworks (COFs) core-shell composites with CoFe 2 O 4 as the core and COFs as the shell were prepare conveniently by the one-pot ultrasonic method, the resultant composites were used as highly efficient and selective nanozyme for electrochemical sensors. By adjusting the COFs ligand and reaction time, the COFs shells with controllable pore sizes, functional groups and shell thickness were designed precisely to improve the efficiency and selectivity of CoFe 2 O 4 @COFs nanozymes. The as-synthesized core-shell CoFe 2 O 4 @COFs nanozymes were convenient for purification and separation, and the materials were analyzed by different characterization methods. The efficiency and selectivity of CoFe 2 O 4 @COFs nanozymes for catalytic performance were evaluated through glucose electrochemical sensing. The CoFe 2 O 4 @COFs glucose sensors exhibited excellent performance with higher sensitivity, better selectivity and stability than pure CoFe 2 O 4 . This study sheds new light on enhancing the catalytic performance of metal oxide nanozymes, which is of great scientific significance and application prospect.