Construction of composite SERS substrate based on black phosphorus/mesoporous ZIF-67 and its selective monitoring of food additives

Semiconductor-based surface-enhanced Raman scattering (SERS) dependent on chemical mechanism has shown favorable selective enhancement and recognition capabilities. However, the limited Raman enhancement capability of conventional semiconductor-based still remains a great challenge in the effective monitoring of trace molecules in a practical complex environment. In this context, a novel two-dimensional composite semiconductor substrate was developed by in-situ growing reticular ZIF-67 mesoporous film upon black phosphorus (BP) nanosheets. An attractive synergistic chemical enhancement was triggered attributed to the efficient continued charge transfer process in the BP/ZIF-67 system. Particularly, a selective SERS enhancement of food additive molecules with different orbital structures was found owing to the coupling degree of intrinsic molecular resonance and photo-induced charge transfer. A sensitive detection of lycopene in beverage samples with a high recovery rate was finally realized by the BP/ZIF-67 composite substrate, which exhibited great potential in practical molecular selective recognition.