Sweetsop-like α-Fe₂O₃@CoNi catalyst with superior peroxidase-like activity for sensitive and selective detection of...

Hydroquinone (HQ) is poorly degradable in the ecological environment and is highly toxic to human health even at a low concentration. The colorimetric method has the advantages of low cost and fast analysis, which provides the possibility for simple and rapid detection of HQ. In this work, a new colorimetric method has been developed for HQ detection based on a peroxidase-like catalyst, α-Fe₂O₃@CoNi. This sweetsop-like α-Fe₂O₃@CoNi catalyst enables H₂O₂ to produce hydroxyl (˙OH), leading to the oxidization of colorless 3,3',5,5'-tetramethylbenzidine (TMB) to blue oxTMB. In the presence of HQ, the blue oxTMB is reduced to colorless, which allows for colorimetric detection of HQ in water samples. This method has been validated by detecting HQ in water samples with high selectivity, rapid response, broad detection range (0.50 to 30 μM), and low detection limit (0.16 μM).