Highly temperature-sensitive and blue upconversion luminescence properties of Bi2Ti2O7:Tm3+/Yb3+ nanofibers by electrospinning

Tailoring of Upconversion Emission in Tm3+/Yb3+-Codoped Y2Mo3O12 Submicron Particles Via Thermal Stimulation Engineering for Non-invasive Thermometry

“…To shed light on the luminescence properties of resultant products, the UC emission spectra of YMO:Tm 3+ /2 x Yb 3+ submicron particles were recorded and are presented in Figure a. As revealed, only the featured emissions of Tm 3+ ions are gained in the UC emission profiles, in which the intense blue emission at 481 nm is assigned to the 1 G 4 → 3 H 6 transition, and the weak emissions centered at 654 and 700 nm are ascribed to the 1 G 4 → 3 F 4 and 3 F 2,3 → 3 H 6 transitions, respectively. , Besides, it is worth noting that the emission intensities are sensitive to the dopant concentration. In particular, the emission intensities increase as the Yb 3+ concentration increases, achieving its maximum value when x = 0.13, as described in Figure b, whereas they start to decrease with further raising the Yb 3+ content.…”

“…Inspired by these, we selected Y 2 Mo 3 O 12 (YMO), which pertains to a member of NTE A 2 Mo 3 O 12 (A stands for a trivalent cation), as the host compound considering its superior NTE characteristics along with lowest anisotropy. − Notably, the investigation on thermometric properties of upconverting materials, in which rare-earth ions acted as activators and sensitizers, mainly focused on Er 3+ , while other rare-earth ions, taking Tm 3+ for example, did not receive enough attention. Thus, to solve this drawback, Tm 3+ was chosen as the activator, and Yb 3+ was also doped together since it can efficiently harvest the near-infrared light, and then transfer the energy to Tm 3+ , , resulting in robust UC emissions. With the aid of the sol–gel method, Tm 3+ /Yb 3+ -codoped YMO submicron particles with diverse Yb 3+ contents were synthesized.…”

Hydrothermal synthesis of anisotropic SrGe4O9:Yb3+/Er3+ nanorods and optimized upconversion luminescence for optical temperature sensing

“…Thus, they are more likely to be synthesized in large quantities and can be used in harsh circumstances such as high temperature and moist environments. 12,13 The oxosalts of germanates are also promising for optical use because of the wide transmittance range and structural diversity and are assembled by different kinds of polynuclear units, such as [Ge 2 O 7 ], [Ge 3 O 9 ], and [Ge 4 O 12 ]. 14,15 The metal germanate crystals have been used for scintillation crystals to detect high-energy particles and rays 16 and can also be employed as a nonlinear optical medium to achieve second harmonic generation (SHG).…”

Multipath optical thermometry realized in CaSc2O4: Yb3+/Er3+ with high sensitivity and superior resolution

“…In particular, the fluorescence intensity ratio ( FIR ) between two thermally coupled energy levels of trivalent rare earth ions is considered to be a promising technology to provide fast and accurate optical thermometry, due to its rapid response capability, high spatial resolution, strong anti‐jamming ability, etc 12‐17 . Up to date, numerous trivalent rare earth ions are used for ratiometric thermometry, such as Er 3+ , Ho 3+ , Tm 3+ , Nd 3+ , and Eu 3+ 18‐25 . Among these ions, Er 3+ is the most widely used activator for temperature sensing which has been realized in an enormous variety of materials, due to the excellent thermal coupling between the green emitting levels 2 H 11/2 and 4 S 3/2 of Er 3+ as well as their strong UC intensity under the excitation of 980 nm excitation with the sensitization of Yb 3+ 26,27 .…”

“…[12][13][14][15][16][17] Up to date, numerous trivalent rare earth ions are used for ratiometric thermometry, such as Er 3+ , Ho 3+ , Tm 3+ , Nd 3+ , and Eu 3+ . [18][19][20][21][22][23][24][25] Among these ions, Er 3+ is the most widely used activator for temperature sensing which has been realized in an enormous variety of materials, due to the excellent thermal coupling between the green emitting levels 2 H 11/2 and 4 S 3/2 of Er 3+ as well as their strong UC intensity under the excitation of 980 nm excitation with the sensitization of Yb 3+ . 26,27 Nevertheless, the thermometric sensitivity and resolution as well as the signal to noise ratio (SNR) of Er 3+typed optical thermometer are still need to be improved.…”