Using ytterbium nitrate pentahydrate (Yb(NO3)3·5H2O), ammonium metavanadate (NH4VO3) and citric acid monohydrate (C6H8O7·H2O) as main raw materials, the YbVO4 was prepared by sol-gel method. The samples were characterized by thermogravimetry differential scanning calorimeter (TG-DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM), diffuse reflection spectrometer (DRS) and Fourier infrared spectrometer (FT-IR). The photocatalytic activity of YbVO4 was studied by using 10 mg/L methyl orange as simulated wastewater. The results show that pure YbVO4 can be prepared by calcining at 500 °C to 900 °C. The surface of YbVO4 sample prepared at different temperatures is porous and irregular. The forbidden band width of YbVO4 sample calcined at 700 °C is about 3.04 eV. Under ultraviolet light conditions, the degradation rate of methyl orange was over 95% after illumination for 30 min with YbVO4 sample calcined at 700 °C. YbVO4 show excellent photocatalytic activity for degradation of methyl orange. This indicates that YbVO4 is a new photocatalyst with wide application prospect in the field of photocatalysis.
Shengtao Liang,Junshan Hu,Ming Xu,Luxiang Xu,Hao Fu
The effect of K + ions doping on YbVO 4 : Er 3+ was studied under the excitation of a 980 nm laser. The intensity of multiple emission peaks increased was found to be enhanced at 527 nm ( 2 H 11/2 → 4 I 15/2 ), 553 nm ( 4 S 3/2 → 4 I 15/2 ), 654 nm ( 4 F 9/2 → 4 I 15/2 ), and 803 nm ( 4 I 9/2 → 4 I 15/2 ), including green, red, and near-infrared spectra. The optimal doping concentration was 0.1 K + ions in YbVO 4 : 0.02Er 3+ . The enhancement of upconversion luminescence is attributed to the presence of defect bands, which facilitate the absorption of excited photons and enable effective energy transfer from abundant electrons to Yb 3+ ( 2 F 5/2 ) and Er 3+ ( 4 I 11/2 ) ions. YbVO 4 : Er 3+ /K + was utilized in a three-mode temperature sensor, employing TCEL modes of 2 H 11/2 / 4 S 3/2 , NTCEL modes of 2 H 11/2 / 4 F 9/2 and 4 S 3/2 / 4 F 9/2 , and single luminescence intensity at I 803 . It exhibited maximum relative sensitivities of 1.36 % (298 K), 0.77 % (398 K), 0.44 % (298 K), and 1.69 % (623 K), respectively, highlighting its potential in high-precision optical temperature sensing applications.
This study explored the multi-mode upconversion luminescence in YbVO 4 : Er 3+ under a 980 nm laser. The optimal doping concentration of Er 3+ ions in YbVO 4 : Er 3+ is 0.02. The phosphor exhibits green (527 nm, 2 H 11/2 → 4 I 15/2 and 553 nm, 4 S 3/2 → 4 I 15/2 ), red (654 nm, 4 F 9/2 → 4 I 15/2 ) and near-infrared emissions (803 nm, 4 I 9/2 → 4 I 15/2 ). A multi-mode temperature sensor of YbVO 4 : Er 3+ was developed, featuring three temperature sensing modes based on the luminescent intensity ratio (LIR) of 2 H 11/2 / 4 S 3/2 thermally coupled level, as well as the LIR of 2 H 11/2 / 4 F 9/2 and 4 S 3/2 / 4 I 9/2 non-thermally coupled levels. Corresponding maximum relative sensitivities were determined to be 1.21 % K −1 at 298 K, 0.93 % K −1 at 298 K, and 0.33 % K −1 at 473 K, respectively. The phosphor demonstrates notable temperature sensitivity, highlighting its potential in optical temperature sensing. This study introduces an innovative platform for crafting multi-mode self-reference optical temperature sensors, presenting substantial advancements in the field.
危险品化学品经营许可证（带存储）