Pr3+ doped Y3GaO6 luminescent thermometer for high temperature conditions

Thermal imaging study of Sm2+ doped SrB4O7 based on time-resolved technology

“…The relative sensitivity is 7.64% K −1 at 500 K while it reaches 9.67% K −1 as the temperature increases to 533 K. This is an excellent sensitivity value for temperature sensing materials, compared with recently reported results (Table 1). 22–27 Furthermore, using the total intensity of the sample rather than a specific wavelength range greatly increases the signal intensity because no signal is likely lost due to wavelength selection. The high sensitivity and excellent signal quality of this method make it promising in thermal sensing applications.…”

Luminescence Thermometry Beyond the Biological Realm

“…As an alternative to the shell encapsulation technique, a study involving LiYF 4 :Yb 3+ ,Er 3+ upconverting microcrystals used varying levels of Cu 2+ doping to reinforce the crystalline host matrix, mitigate defects, and reduce thermal quenching of the luminescence response for thermometry up to 873 K . Recent work identified temperature-dependent cross-relaxation processes in Pr 3+ -doped Y 3 GaO 6 as a mechanism for achieving ratiometric thermometry from room temperature up to approximately 800 K . This study also found that varying the Pr 3+ concentration modified the thermal sensitivity across the same temperature range.…”

“…19 In the most extreme cases, relevant industrial applications for luminescence thermometry such as evaluating thermal barrier coatings for gas turbine blades can require operating temperatures as high as 1500 K. 141 degradation around 600 K, 142 with noticeable sensitivity losses occurring at even lower temperatures. 143 Several studies have improved upon the high-temperature capabilities of UCNPs and related upconverting materials to measure temperatures as high as 1000 K. 19,140,141 Meanwhile, diamond has exceptional high-temperature stability, and temperature-dependent responses from NV centers including all-optical 86 and ODMR 79 signals remain robust up to approximately 700 K. Geitenbeek et al 141 utilized bare NaYF 4 :Yb 3+ ,Er 3+ UCNPs for high-temperature thermometry up to 600 K; however, above these temperatures the particles melted and fused together. Incorporating a SiO 2 shell around the UCNP core prevented this issue, thereby enabling thermometry up to 900 K. A similar study found that a SiO 2 shell enabled higher temperature measurements with LiLuF 4 :Yb 3+ , Er 3+ UCNPs up to 800 K. 140 As an alternative to the shell encapsulation technique, a study involving LiYF 4 :Yb 3+ ,Er 3+ upconverting microcrystals used varying levels of Cu 2+ doping to reinforce the crystalline host matrix, mitigate defects, and reduce thermal quenching of the luminescence response for thermometry up to 873 K. 142 Recent work identified temperature-dependent cross-relaxation processes in Pr 3+ -doped Y 3 GaO 6 as a mechanism for achieving ratiometric thermometry from room temperature up to approximately 800 K. 143 This study also found that varying the Pr 3+ concentration modified the thermal sensitivity across the same temperature range.…”

“…143 Several studies have improved upon the high-temperature capabilities of UCNPs and related upconverting materials to measure temperatures as high as 1000 K. 19,140,141 Meanwhile, diamond has exceptional high-temperature stability, and temperature-dependent responses from NV centers including all-optical 86 and ODMR 79 signals remain robust up to approximately 700 K. Geitenbeek et al 141 utilized bare NaYF 4 :Yb 3+ ,Er 3+ UCNPs for high-temperature thermometry up to 600 K; however, above these temperatures the particles melted and fused together. Incorporating a SiO 2 shell around the UCNP core prevented this issue, thereby enabling thermometry up to 900 K. A similar study found that a SiO 2 shell enabled higher temperature measurements with LiLuF 4 :Yb 3+ , Er 3+ UCNPs up to 800 K. 140 As an alternative to the shell encapsulation technique, a study involving LiYF 4 :Yb 3+ ,Er 3+ upconverting microcrystals used varying levels of Cu 2+ doping to reinforce the crystalline host matrix, mitigate defects, and reduce thermal quenching of the luminescence response for thermometry up to 873 K. 142 Recent work identified temperature-dependent cross-relaxation processes in Pr 3+ -doped Y 3 GaO 6 as a mechanism for achieving ratiometric thermometry from room temperature up to approximately 800 K. 143 This study also found that varying the Pr 3+ concentration modified the thermal sensitivity across the same temperature range. Other work involving UCNPs used a NIR ratiometric thermometry signal based on the 2 F 5/2 to 2 F 7/2 transition of Yb 3+ and the 3 H 4 to 3 H 6 transition of Tm 3+ , which, notably, are non-TCLs, in YVO 4 :Yb 3+ ,Tm 3+ UCNPs for thermometry up to 1000 K. 19 The non-TCLs studied showed significantly better thermal sensitivity and temperature resolution compared to TCLs of Tm 3+ at elevated temperatures, highlighting the possibility that underexamined luminescence signals lacking good resolution and sensitivity at room temperature could potentially be wellsuited for high-temperature thermometry.…”

“…High-temperature measurements can also facilitate fundamental studies of material properties under extreme conditions. Many UCNPs suffer from catastrophic thermal quenching and host material degradation around 600 K, with noticeable sensitivity losses occurring at even lower temperatures . Several studies have improved upon the high-temperature capabilities of UCNPs and related upconverting materials to measure temperatures as high as 1000 K. ,, Meanwhile, diamond has exceptional high-temperature stability, and temperature-dependent responses from NV centers including all-optical and ODMR signals remain robust up to approximately 700 K.…”