Surface Modification Of Alpha-Fe2o3 Nanoparticles To Develop As Intrinsic Photoluminescent Probe And Unprecedented Photocatalyst

Herein, we demonstrate the emergence of intrinsic multicolor fluorescence in alpha-Fe2O3 nanoparticles (NPs) from blue, cyan, to green, upon functionalization and further surface modification with a small organic ligand, Na-tartrate. Furthermore, we have found an excellent photocatalytic property of the functionalized alpha-Fe2O3 NPs in the decoloration of a model water contaminant. Detailed characterization of alpha-Fe2O3 NPs before and after functionalization were carried out by X-ray diffraction and transmission electron microscopy. Proper investigation through UV-visible absorption and photoluminescence study along with theoretical support from literature reveals that ligand-to-metal charge transfer from tartrate ligand to lowest unoccupied energy level of Fe3+ of the NPs and d-d transitions centered over Fe3+ ions in the NPs play the key role in the generation of multiple fluorescence from the ligand functionalized alpha-Fe2O3 NPs. Vibrating sample magnetometry measurements exhibit magnetic behavior of Fe2O3 NPs changed considerably after surface modification. We believe that the developed ferromagnetic, multicolor fluorescent alpha-Fe2O3 NPs would pioneer new opportunities toward diverse applications.