Eu, Tb- and Er, Yb-Doped α-MoO Nanosheets for Optical Luminescent Thermometry.

Here we report a novel synthesis approach for the preparation of α-MoO:Ln materials employing a two-step synthesis. Additionally, in this work the α-MoO:Ln materials are reported as potential optical thermometers for the first time. In this synthesis approach, first MoS 2D nanosheets were prepared, which were further heat treated to obtain α-MoO. These materials were fully characterized by powder X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray fluorescence (XRF), thermogravimetry (TG) and differential thermal analysis (DTA), transmission electron microscopy (TEM), and luminescence spectroscopy. Temperature-dependent luminescence measurements were carried out to determine the optical thermometric properties of two different types of α-MoO:Ln materials (Eu/Tb downshifting and Er/Yb upconversion luminescence systems). We demonstrate in this study that this class of material could be a potential candidate for temperature-sensing applications.