The
MnFe2O4 nanoparticle has been among the most frequently chosen systems due to its diverse applications in the fields ranging from medical diagnostics to magnetic
hyperthermia and site-specific
drug delivery. Although numerous efforts have been directed in the synthesis of monodisperse
MnFe2O4 nanocrystals, unfortunately, however, studies regarding the tuning of surface property of the synthesized nanocrystals through functionalization are sparse in the existing literature. Herein, we demonstrate the emergence of intrinsic multicolor fluorescence in
MnFe2O4 nanoparticles from blue, cyan, and green to red, upon functionalization and further surface modification with a small organic
ligand, Na-
tartrate. Moreover, we have found an unprecedented photocatalytic property of the functionalized
MnFe2O4 nanoparticles in the degradation of a model water contaminant. Detailed characterization through XRD, TEM, and FTIR confirms the very small size and functionalization of
MnFe2O4 nanoparticles with a biocompatible
ligand. Proper investigation through UV-visible absorption, steady-state and time-resolved photoluminescence study reveals that
ligand-to-
metal charge-transfer transition from the
tartrate ligand to the lowest unoccupied energy level of Mn(2+/3+)or Fe(3+) of the NPs and Jahn-Teller distorted
d-d transitions centered over Mn(3+)
ions in the NPs play the key role behind the generation of multiple fluorescence from the
ligand-functionalized
MnFe2O4 nanoparticles. VSM measurements indicates that the superparamagnetic nature of
MnFe2O4 nanoparticles remains unchanged even after surface modification. We believe that the developed superparamagnetic, multicolor fluorescent
MnFe2O4 nanopaticles would open up new opportunities as well as enhance their beneficial activities toward diverse applications.