Hollow POM@MOF‐derived Porous NiMo6@Co3O4 for Biothiol Colorimetric Detection

Abstract Developing highly active and sensitive peroxidase mimics for L ‐cysteine ( L ‐Cys) colorimetric detection is very important for biotechnology and medical diagnosis. Herein, polyoxometalate‐doped porous Co 3 O 4 composite (NiMo 6 @Co 3 O 4 ) was designed and prepared for the first time. Compared with pure and commercial Co 3 O 4 , NiMo 6 @Co 3 O 4 (n) composites exhibit the enhanced peroxidase‐mimicking activities and stabilities due to the strong synergistic effect between porous Co 3 O 4 and multi‐electron NiMo 6 clusters. Moreover, the peroxidase‐mimicking activities of NiMo 6 @Co 3 O 4 (n) composites are heavily dependent on the doping mass of NiMo 6 , and the optimized NiMo 6 @Co 3 O 4 (2) exhibits the superlative peroxidase‐mimicking activity. More importantly, a sensitive L ‐Cys colorimetric detection is developed with the sensitivity of 0.023 μM −1 and the detection limit at least 0.018 μM in the linear range of 1–20 μM, which is by far the best enzyme‐mimetic performances, to the best our knowledge.