JOURNAL OF LUMINESCENCE
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2021
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IF 3.599
Xuefei Ren,Yi Zhang,Chang Su,Jingwen Zhan,Linyan Fu,Yunlong Yang,Xiyuan Sun,Jian Wang,Xing Feng
Far-red emitting Sr 3 NaTaO 6 : Mn 4+ and Sr 3 NaTaO 6 : Mn 4+ , Ba 2+ phosphors were successfully synthesized by high-temperature solid-state method for the first time. The crystal structure and luminescence properties of phosphors were studied by X-ray diffraction (XRD), photoluminescence (PL), thermal stability, UV–vis spectroscopy and CIE color coordinate in detail. The Sr 3 NaTaO 6 : Mn 4+ phosphor exhibits an intense emission peak at 692 nm under the excitation of 365 nm, which matches well with the absorption spectra of plant pigments of chlorophyll a and b , phytochrome P R and P FR . Besides, by co-doping of Ba 2+ ions, the emission intensity of Sr 3 NaTaO 6 : Mn 4+ phosphors were enhanced 1.1–1.5 times and an internal quantum efficiency (IQE) of 75.1% was obtained. Finally, a LED device was fabricated with the Sr 3 NaTaO 6 : 0.3%Mn 4+ , 0.45%Ba 2+ phosphor and showed an effective promotion on the average stem length, fresh weight, dry weight and chlorophyll content of wheat. The result shows that Sr 3 NaTaO 6 : 0.3%Mn 4+ , 0.45%Ba 2+ phosphor may have a potential application in the fields of plant growth lighting LEDs.
研究领域:
材料科学
·
植物学
✓ 已验证
产品关联
DOI
高影响因子
INFRARED PHYSICS & TECHNOLOGY
·
2023
·
IF 3.3
Bin Duan,Changchun Ding,Yuxiang Wu,Yongqiang Li,Wei Jin,Fengyi Wang,Junshan Hu
The present work investigates the near-single green emission properties of Ba 2+ doped Ca 9 Y(VO 4 ) 7 : Yb 3+ /Er 3+ upconversion luminescence. The Ba 2+ doped Ca 9 Y(VO 4 ) 7 : Yb 3+ /Er 3+ phosphors were successfully synthesized via the high-temperature solid-phase method. XRD pattern analysis showed that Ca 9 Y(VO 4 ) 7 : Yb 3+ /Er 3+ /Ba 2+ was a single phase, and Ba 2+ doping did not induce heterophase phase. Under 980 nm near-infrared laser irradiation, Ca 9 Y(VO 4 ) 7 : Yb 3+ /Er 3+ /Ba 2+ phosphors emit strong green luminescence (530 nm, 2 H 11/2 → 4 I 15/2 , 557 nm, 4 S 3/2 → 4 I 15/2 ) and weak red luminescence (664 nm, 4 F 9/2 → 4 I 15/2 ). The upconversion green-red luminescence integral intensity ratio of Ca 9 Y(VO 4 ) 7 : Yb 3+ /Er 3+ /Ba 2+ phosphor is 32.1. This enhancement can be attributed to the presence of defect bands that facilitate excitation photon absorption and efficient energy transfer from abundant electrons into Yb 3+ ( 2 F 5/2 ) and Er 3+ ( 4 I 11/2 ) ions. More importantly, the maximum S A and S R of Ca 9 Y(VO 4 ) 7 : Yb 3+ /Er 3+ /Ba 2+ phosphor as a temperature sensor are 1.44 % K −1 (at 548 K) and 1.28 % K −1 (at 298 K), respectively.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2024
·
IF 5.8
Tianzhi Jiang,Xuejiao Wang,Renguang Ye,Youjie Hua,Xinfeng Jin,Weigang Guo,Guoqing Liu,Zhiqiang Long,Buqing Zhang,Gongxun Bai,Junjie Zhang,Shiqing Xu
The quenching of luminescence in Er 3+ /Yb 3+ co-doped with Tm 3+ presents a dilemma as it substantially diminishes thermometric performance. In this study, Y 2 O 2 S: Er 3+ /Yb 3+ /Tm 3+ phosphors were synthesized using a homogeneous precipitation method combined with a sulfurization process. In addition, three sets of fluorescence intensity ratio (FIR) models were designed, which have self-calibration function. The effects of incorporation of Li + or Li + /Ba 2+ on the up-conversion luminescence (UCL) intensity and thermometric performance of the phosphors were systematically studied. The results show that the introduction of Li + or Li + /Ba 2+ co-doping leads to lattice distortion and the formation of oxygen ion vacancies in the lattice, which further accelerates the energy transfer process and mixes the charge transfer states , and ultimately dramatically improves the UCL and thermometric performance. The introduction of Li + and Li + /Ba 2+ co-doping enhanced the UCL of the materials by about 3.7 times and 5.6 times compared to Y 2 O 2 S: Er 3+ /Yb 3+ /Tm 3+ . When based on nonthermally coupled levels (NTCLs), the S r-max of Li + /Ba 2+ co-doped sample is 0.080 K −1 at 573 K, which is 87 % higher than that based on TCLs. These findings not only provide a new avenue for improving the UCL and thermometric performance but also provide an accurate self-calibration FIR model over a wide temperature range.
研究领域:
材料科学
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光学
·
物理学
✓ 已验证
DOI
高影响因子
CHEMISTRY OF MATERIALS
·
2020
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IF 9.567
Qian-Ming Huang,Chun-Li Hu,Bing-Ping Yang,Ru-Ling Tang,Jin Chen,Zhi Fang,Bingxuan Li,Jiang-Gao Mao
The first polar alkaline-earth metal molybdenum iodate, Ba2[MoO3(OH)(IO3)2]IO3, with a Λ-shaped [MoO3(OH)(IO3)2]3– functional motif, was rationally designed. A zero-dimensional (0D) [MoO3(OH)(IO3)2]3– unit is derived from 0D [MoO2(OH)(IO3)3]2– polyanion through anionic mono-site substitution. Ba2[MoO3(OH)(IO3)2]IO3 possesses a strong phase-matchable second-harmonic-generation (SHG) response of approximately 8 times that of benchmark KH2PO4 (KDP), a broad transparent spectral region from near-ultraviolet to mid-infrared (0.29–10.6 μm), a large band gap of 3.78 eV, and a high laser-induced damage threshold (LDT) of 92.3 MW cm–2. The results suggest that Ba2[MoO3(OH)(IO3)2]IO3 can be potentially applied in the mid-infrared nonlinear optical field. Theoretical calculations demonstrate that the large SHG response of the title compound originates mainly from the Λ-shaped [MoO3(OH)(IO3)2]3– functional unit. From multisite substitution to mono-site substitution, this work provides a more generic route to synthesize SHG materials.
研究领域:
材料科学
·
晶体化学
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Bioengineering and Biotechnology
·
2022
·
IF 6.064
He Bin,Yang Liyan,Yang Dengfeng,Jiang Minguo,Ling Chengjin,Chen Hailan,Ji Feng,Pan Lixia
N-acetylglucosamine (GlcNAc) is widely used in nutritional supplement and is generally produced from chitin using chitinases. While most GlcNAc is produced from colloidal chitin, it is essential that chitinases be acidic enzymes. Herein, we characterized an acidic, highly salinity tolerance and thermostable chitinase AfChiJ, identified from the marine fungus Aspergillus fumigatus df673. Using AlphaFold2 structural prediction, a truncated Δ30AfChiJ was heterologously expressed in E. coli and successfully purified. It was also found that it is active in colloidal chitin, with an optimal temperature of 45°C, an optimal pH of 4.0, and an optimal salt concentration of 3% NaCl. Below 45°C, it was sound over a wide pH range of 2.0–6.0 and maintained high activity (≥97.96%) in 1–7% NaCl. A notable increase in chitinase activity was observed of Δ30AfChiJ by the addition of Mg2+, Ba2+, urea, and chloroform. AfChiJ first decomposed colloidal chitin to generate mainly N-acetyl chitobioase, which was successively converted to its monomer GlcNAc. This indicated that AfChiJ is a bifunctional enzyme, composed of chitobiosidase and β-N-acetylglucosaminidase. Our result suggested that AfChiJ likely has the potential to convert chitin-containing biomass into high-value added GlcNAc.
研究领域:
生物技术
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生物化学
·
酶学
·
海洋生物学
·
真菌生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Yaru Wang,Peng Zhang,Shuxin Zhang,Yukun Sun,Jiulin Wang,Xiaoqin Zeng,Yanna NuLi
The air cathodes impact the electrochemical performance of primary Mg-air batteries greatly, in which the activity of catalysts plays a decisive role. Perovskites attract significant attention for their high oxygen reduction reaction (ORR) catalytic activity, unique structure, simple synthesis, and low cost. Herein, a series of La 1-x Ba x Ni 0.5 Mn 0.5 O 3 (x = 0.1, 0.2, 0.3, 0.4, 0.5) catalysts fabricated by substituting Ba 2+ for La 3+ at the A-sites of LaNi 0.5 Mn 0.5 O 3 are reported. As a result, the catalytic performance toward ORR exhibits a volcano curve with the increase of doping amount and the highest catalytic activity was achieved at 30 % of Ba 2+ content. Importantly, the experimental and computational results explain the enhancement by the large O 2 adsorption capacity, the formation of oxygen vacancies , the increase in the content of Mn 3+ as an adsorption active site, and the upshift of the Mn-3d band center toward the Fermi level, thereby facilitating the O 2 adsorption and reducing the energy barrier of the rate determining step of ORR. The Mg-air battery with the La 0.7 Ba 0.3 Ni 0.5 Mn 0.5 O 3 catalyst displays a high discharge voltage of 1.37 V and a maximum power density of 65.224 mW · cm - 2 . Therefore, this new ORR catalyst presents great potential in practical Mg-air batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）