Motivated from our previous studies on the upconversion properties of BaMgF:Yb,Tb phosphor, here we investigated the upconversion properties of BaMgF:Yb,Er phosphor. We demonstrate a two-way versatile approach for the fine-tuning of emission from green to the red region, by varying the dopant concentration and adjusting the pulse width of an infrared laser. The mechanism involved in tuning the emission color by laser power and pulse width variation was illustrated in detail. The temperature dependent upconversion spectra were studied by analyzing the fluorescence intensity ratio of the thermally coupled levels. The maximum sensitivity obtained is 83.29 × 10 K at 583 K, which is much higher than the temperature sensitivity reported for other fluoride based materials. Moreover, the influence of the excitation power density on the ability of the phosphor for temperature sensing was also investigated. We obtained a maximum (∼415 K) temperature detection at 2563 mW laser power. The obtained results illustrate the potential use of BaMgF:Yb,Er phosphor in an optical thermometer due to its highly sensitive temperature detection ability.

In this work we have comprehensively studied the up-conversion (UC) properties of BaMgF:Yb,Tb phosphor for the first time. BaMgF:Yb,Tb phosphors were prepared by a simple and low cost precipitation method. To determine the influence of dopant concentration on luminescence properties, the corresponding UC luminescence spectra of BaMgF:Yb,Tb phosphors were studied under NIR excitation. Emission spectra under NIR excitation reveal the vital role of Tb concentration in spectral tuning from the blue to green region. The UC decay curves were also studied to explore the possible energy transfer (ET) mechanisms between Yb and Tb. The results reported here are expected to provide an approach for better understanding ET mechanisms in many Yb/Tb codoped UC phosphors. This study will be helpful in applications where precisely defined optical transitions is an essential criterion.

Enhancing upconversion, temperature sensing and cathodoluminescence in the CaMoO4:Er3+/Yb3+ nanophosphor via K+/Na+ simultaneous codoping.

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