Efficient Color Tunable ZnWO4:Er3+-Yb3+ Phosphor for High Temperature Sensing

The single monoclinic phase with nano-structured crystallites in the ZnWO
₄
: Er
³⁺
-Yb
³⁺
phosphor have been detected from structural investigations by using the X-ray diffraction (XRD) analysis. The spectral studies performed in the codoped phosphor upon 980 nm excitation emit radiations within the UV- NIR wavelength region. Diffuse reflectance and Fourier transform infrared (FTIR) analysis have been done to identify the presence of active ions and impurities in the prepared phosphor. The pump power dependence study results in green to red intensity ratio variation and thus a tuning in color of emitted light is observed. The observed emissions have been explained on the basis of excited state absorption (ESA), energy transfer (ET), and temporal evolution analysis. The temperature sensing performance of synthesized material studied upto ~798 K results the highest sensor sensitivity of about 14.63 × 10
^-3
K
^-1
which confirms the suitability of present material for high temperature sensing with very good sensitivity.