Benzimidazole: Dramatic luminescence turn-on by ZnO nanocrystals

• Synthesized sensor emits fluorescence at 362 nm.
• It is sensitive to detect and estimate ZnO at micromolar level.
• Benzimidazole is adsorbed on the surface of semiconductor.

A benzimidazole-based receptor 2-(4-fluorophenyl)-1-phenyl-1H-benzo[d]imidazole [FPPBI] has been designed, synthesized and characterized by 1H NMR, 13C NMR, mass and single crystal XRD. Absorption, emission, lifetime and cyclic voltammetry have been made to deduce the interaction between FPPBI and ZnO nanocrystals. FPPBI act as a new host for ZnO nanocrystals that enhance its luminescence. The apparent binding constant has been obtained. Adsorption of the FPPBI on ZnO nanocrystals lowers the HOMO energy level of the FPPBI. The strong adsorption of the FPPBI on the surface of ZnO nanocrystals is likely due to the chemical affinity of the nitrogen atom of the FPPBI to the zinc ion on the surface of nanocrystals.

Figure optionsDownload as PowerPoint slide