Sulfur vacancy-rich CuS nanoparticles anchored on N-doped carbon nanofibers for electrochemical and colorimetric dual-mode sensing of hydroquinone

Efficient and sensitive detection of hydroquinone (HQ) in aquatic environments is paramount for environmental and human health protection. In this study, the CuS nanoparticles are successfully anchored on N-doped carbon nanofibers (CuS/N-CNFs) by electrospinning and sulfuration strategies. The resultant CuS/N-CNFs nanozyme catalyst exhibits abundant sulfur vacancies and mesoporous carbon structures, resulting in excellent electrocatalytic activity for the oxidation of HQ. Furthermore, the catalyst demonstrates significant peroxisase-like activity, which can catalyze colorless 3,3′, 5,5′ −tetramethylbenzidine (TMB) to blue oxTMB in the presence of H 2 O 2 . The mechanism investigations reveal that •OH radical serves as the main active species in this process. Based on these unique properties, a novel electrochemical and colorimetric dual-mode sensor is constructed for HQ detection with linear ranges of 1–614 μM and 1–57 μM, respectively, and the limit of detections (LODs) of 0.293 and 0.621 μM (S/N = 3). Moreover, the established HQ sensor platform is expected to be potential candidate for practical applications due to its satisfactory sensitivity and selectivity in real water samples.