Oxygen vacancy enhanced photoelectrochemical performance of Bi2MoO6/B, N co-doped graphene for fabricating lincomycin aptasensor

Abstract Oxygen defect-engineered is an important strategy to improve the photoelectric activity of materials. Herein, a facile one-pot solvothermal method was utilized to synthesize visible light-responsive photoactive Bi 2 MoO 6 nanoparticles anchored boron and nitrogen co-doped graphene (BNG) nanosheets nanocomposites with oxygen vacancy. The incorporation of BNG nanosheets increased the oxygen vacancies amounts on Bi 2 MoO 6 remarkably, and the presences of oxygen vacancies can be beneficial to broaden the absorption range. The absorption edge of Bi 2 MoO 6 /BNG was widened from 500 nm to 550 nm compared to Bi 2 MoO 6 , and the charge transfer was accelerated to improve the photoactive of Bi 2 MoO 6 /BNG. Under visible light illumination, the photoelectrochemical (PEC) response of the as-prepared Bi 2 MoO 6 /BNG was 11.6-fold, 6.7-fold, 3.1-fold and 2.4-fold higher than that of pristine Bi 2 MoO 6 , Bi 2 MoO 6 /graphene, Bi 2 MoO 6 /nitrogen doped graphene and Bi 2 MoO 6 /boron doped graphene. Using Bi 2 MoO 6 /BNG nanocomposites with the superior PEC performance as photoactive materials in combination with specifically recognized lincomycin (LIN) aptamer, a highly efficient PEC aptasensor was successfully constructed for sensitive analysis of LIN. Under optimal conditions, the proposed PEC aptasensor exhibited excellent analytical performance for LIN with a wide linear response of 1 × 10 −11 to 1 × 10 −6  mol L −1 along with a low detection limit of 3.7 × 10 −12  mol L −1 (defined as S / N  = 3). The as-prepared Bi 2 MoO 6 /BNG nanocomposites exhibit excellent visible light response and PEC performance, indicating its potential applications in PEC biosensor.