One-Pot Synthesis of Homogeneous EuF ₃ Nanoplates: A Near-Ultraviolet Light-Induced Red-Emitting Bifunctional Platform for in vitro Cell Imaging and Solid-State Lighting

We reported a new approach to prepare the homogenous EuF ₃ nanoplates and discussed their potential applications. Upon 396 nm excitation, the EuF ₃ nanoplates exhibited the visible emissions with high color purity of 84.7%. The monitored photoluminescence emission spectrum indicated that the Eu ³⁺ ions took the high symmetry positions in the host lattices which was further confirmed via the theoretical calculation based on the Judd-Ofelt theory. The thermal quenching performance of the EuF ₃ nanoplates was analyzed by the temperature-dependent photoluminescence emission spectra and the activation energy was decided to be 0.28 eV. With the aid of the near-ultraviolet chip and EuF ₃ nanoplates, a red-emitting light-emitting diode device was prepared so as to identify the feasibility of the EuF ₃ nanoplates for solid-state lighting. Additionally, the cell viability of the EuF ₃ nanoplates as well as their fluorescence imaging behaviors in the A549 lung cancer cells was also investigated. The observed results demonstrated that the EuF ₃ nanoplates were bifunctional platform for in vitro cell imaging and solid-state lighting.