Differential recognition of anions with ZnO based urea-coupled sensors

With the emergence of nanoparticles as a class of attractive probes for selective sensors, a need arise for the development of nanoparticles based multifunctional sensors. Herein, a simple strategy is explored for the differential recognition of two different anions. The anion receptors have been coated on the surface of ZnO and the product was characterized with SEM, XRD, EDX, UV-vis absorption and fluorescence spectroscopy. A comparison of anion recognition properties of pure host and the same host coated on ZnO revealed magnificent change in the recognition properties. The fluoride binding leads to red shift in the absorption spectrum of receptor and SO42− binding causes blue shift. These results demonstrated that our design strategy offers an effective way to develop an excellent differential sensor for anions.