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In this study the non-hydrolytic sol gel methodology was used to synthesized gadolinium vanadate particles doped with different molar ratios of the Er3+ and Yb3+ ions. The sol gel synthesis, lanthanide ion chlorides and vanadium alkoxide were used as precursors. The resulting powders were treated at 800 oC and characterized by X-ray diffraction and photoluminescence properties. The X-ray diffractogram displayed peaks attributed to the gadolinium vanadate matrix. Photoluminescence helped to evaluate the Fluorescence Intensity Ratio (FIR), parameter for understanding the nanothermometer property. The FIR of the GdVO4: Er3+/Yb3+ samples containing different molar ratios of the Er3+ and Yb3+ ions increased as a function of laser power, which indicated that the local temperature increased. The excitation spectra obtained at fixed wavelengths of 525 and 555 nm displayed bands at 322, 379, and 489 nm, ascribed to the charge transfer band and Er3+ ion levels. Upon excitation at 322 nm, the emission spectra in the visible region presented intense bands at 525 and 555 nm, due to Er3+ ion emission, and excitation at 322 nm, the emission in the infrared region, 980 and 1550 nm, were observed. The system is a candidate can be employed as temperature sensor.

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