Morphology control and temperature sensing properties of micro‐rods NaLa(WO 4 ) 2 :Yb 3+ ,Er 3+ phosphors

Uniform spindle‐like micro‐rods NaLa(WO 4 ) 2 :Yb 3+ ,Er 3+ phosphors are prepared by the solvothermal method in the text. Controllable morphology of NaLa(WO 4 ) 2 crystal can be obtained by adjusting the prepared temperature, PH value, complexing agent content, and solvent ratio. Uniform NaLa(WO 4 ) 2 :Yb 3+ ,Er 3+ micro‐rods of 1.8 μm in length and 0.5 μm in width are synthesized at a low temperature of 120°C. The prepared NaLa(WO 4 ) 2 :Yb 3+ ,Er 3+ phosphors present green upconversion luminescence under 980 nm excitation, luminescence intensity reaches to maximum at the Yb 3+ and Er 3+ concentration of 6 and 2 mol%. The temperature performance of the NaLa(WO 4 ) 2 :Yb 3+ ,Er 3+ phosphors are evaluated based on thermal coupling technology. Temperature dependence of the two green emissions ratio of Er 3+ ion is obtained, and the sensitivity of the sample can be calculated, the maximum sensitivity of NaLa(WO 4 ) 2 :Yb 3+ ,Er 3+ is up to 0.019 K −1 at the sample temperature of 564 K.