Ultrasensitive sandwich-type photoelectrochemcial oxytetracycline sensing platform based on MnIn2S4/WO3 (Yb, Tm) functionalized rGO film

Abstract

• A PEC detection platform based on MnIn 2 S 4 /WO 3 (Yb, Tm) functionalized rGO film was constructed. • The fast charge separation and great optical absorption were beneficial to amplify detection signal. • The sandwich-type recognition model was applied to promote specificity and increase sensitivity. • The PEC sensing system showed great property for detecting oxytetracycline in water. A novel photoelectrochemical (PEC) detection system was constructed based on reduced oxide graphene (rGO) film as substrate and MnIn 2 S 4 /WO 3 (Yb, Tm) Z-scheme heterojunction as signal matrix. Benefiting from the accelerated photo-generated carrier separation and enhanced optical absorption, the application of MnIn 2 S 4 /WO 3 (Yb, Tm) as photoactive material is propitious to boost the photocurrent detection signal. With great electron transfer property, rGO further promotes the separation of photo-generated carrier, resulting in the amplification of detection signal. The sandwich-type detection mode is introduced to increase the sensitivity and enhance the specificity. Under the optimal conditions, the PEC detection system presented great property in oxytetracycline (OTC) detection with a linear range from 4 × 10 - 5 nM to 5 × 10 - 2 nM and a low limit of detection as 1.3 × 10 - 5 nM (5.99 × 10 - 3 ng L - 1 ). Give these merits, the proposed PEC sensing system provides a new horizon for sensitive detection of environmental contaminants and biological targets.