Synthesis, Neutron Diffraction, and DFT Studies of NaLa(WO 4 ) 2 : Yb 3+ /Er 3+ ; NIR Induced Green Fluorescent Bifunctional Probes for In Vitro Cell Imaging and Solid State Lighting

The combined neutron diffraction, DFT, and Raman analysis unraveled lattice phonons of ∼912 cm−1 in the UC host. Detailed microscopy studies uncovered the presence of high-density dislocations in NaLa0.865Er0.035Yb0.1(WO4)2 nanomaterials leading to improved phonon scattering. Besides, excellent biocompatibility towards E coli, S aureus, C albicans, and HeLa cell lines, our green-emitting upconversion NaLa0.865Er0.035Yb0.1(WO4)2 bulk and nanophosphors find potential use in solid-state lighting and in vitro cell imaging respectively.