Rationally designed hierarchical hollow ZnCdS@MoS2 heterostructured cages with efficient separation of photogenerated carriers for photoelectrochemical aptasensing of lincomycin

Abstract

The construction of heterostructures is considered as an effective strategy to facilitate migration of photogenerated carriers and boost the photoelectrochemical (PEC) performances. Herein, a novel hierarchical hollow ZnCdS@MoS2 heterostructured cages derived from metal-organic frameworks (MOFs) were synthesized by solvothermal and hydrothermal methods. The morphology of MoS2 grown on the surface of ZnCdS polyhedral cages could be well-controlled by changing the experimental conditions. Under visible light irradiation, compared with pristine ZnCdS and MoS2, the PEC response of the ZnCdS@MoS2 was enhanced by 3.1-fold and 47.3-fold, respectively. The enhanced PEC properties were ascribed to the synergy between tailored hierarchical hollow structure and close contact heterojunction interface, which can promote visible-light harvesting, accelerate charge migration, and curb recombination of photogenerated carriers. Benefiting from the remarkable PEC performance of hierarchical hollow ZnCdS@MoS2 heterostructured cages, a label-free PEC aptasensor platform was constructed for lincomycin detection with excellent selectivity and sensitivity. The developed PEC aptasensor displayed a wide liner response of 1×10−10 to 3 × 10-7 mol L-1 with a low detection limit of 7.6 × 10-11 mol L-1. This work demonstrates the marvelous potential of hierarchical hollow ZnCdS@MoS2 heterostructured cages in PEC sensing applications. Most importantly, this work opens an avenue for the design and synthesis of MOF-derived novel heterostructures.