APPLIED CATALYSIS B-ENVIRONMENTAL
·
2019
·
IF 14.229
Yaru Wang,Jianjun Zhao,Xianqiang Xiong,Shengwei Liu,Yiming Xu
Anatase TiO 2 is the most studied environmental photocatalyst, but its efficiency is still not high enough to enable application. Herein we report a positive effect of Ni 2+ ions on the photocatalytic reaction in neutral aqueous solution. On addition of 1 mM Ni(ClO 4 ) 2 , the rates of phenol oxidation on TiO 2 and 0.5 wt.% Pt/TiO 2 increased by factors of 2.1 and 8.0, respectively. Meanwhile, the formation of organic intermediate was reduced, and the removal of total organic content was enhanced. Interestingly, Ni 2+ concentration did not change with irradiation time. Moreover, a maximum rate of phenol degradation was observed with Ni 2+ ions, occupying half the surface of TiO 2 or Pt/TiO 2 , where Ni(OH) + was more active than Ni(OH) 2 . X-ray photoelectron spectroscopy identified a Ni 3+ species produced in absence of phenol. A (photo)electrochemical study revealed that Ni 2+ oxidation was favored over H 2 O oxidation, whereas Ni 2+ and Pt inhibited and facilitated O 2 reduction, respectively. It is proposed that the adsorbed Ni(OH) + on TiO 2 is oxidized to Ni 3+ by the photogenerated holes of TiO 2 , followed by regeneration through phenol oxidation. The Ni 2+ -catalyzed organic oxidation then promotes the Pt-catalyzed O 2 reduction, and vice visa, resulting into the greatly improved efficiency of charge separation. This work highlights the possibility of Ni 2+ ions as the hole mediator of organic oxidation over a semiconductor.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Silicon
·
2020
·Vol. 14
·期 2
·385-392
·
IF 1.499
Wen Qin,Jiang Chunxia,Liu Wanqiang,Zeng Zhi,Gao Jinwei,Zheng Yuhui
Quantum dots generate unique luminescent and chemical properties due to the ultra-small particle sizes. In this contribution, a novel silicon nanoparticles (Si-NPs)-based platform has been established via (3-aminopropyl) trimethoxysilane (APS) and ascorbic acid (AA) as raw materials within only 30 min. A switched off effect has been achieved for the determination of Ni 2+ ions and the strategy has been simply realized by recording the luminescence changes in the green band of Si-NPs. This developed approach possesses a variety of merits such as label free, low cost, easy post-treatment and convenient operations. The linear equation range is yielded between 0 and 20 μM with the detection limit of 1.73 μM. The nano-sensor provides a versatile route for the monitoring of mercury ions in practical environments.
研究领域:
分析化学
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纳米技术
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Guanliang Yu,Weirong Wang,Chun Jiang
Adjusted crystal fields can lead to new hybrid materials with promising optical performance. Transition metal ions (TMIs) with d-d electron transitions are sensitive to their surroundings and can be ideal candidates for crystal field research. Herein, we have selected single Ni 2+ -doped spinel oxide nanocrystals as a model system to systematically explore luminescence mechanisms in different crystal fields. Ni 2+ -doped ZnAl 2 O 4 , ZnGa 2 O 4 , and ZnCr 2 O 4 nanospinels with broad near-infrared (NIR) emission bands fully cover the second biological window (1100–1400 nm). We have developed a ZnX 2 O 4 (X = Al, Ga or Cr) (ZXO) spinel framework system using a melting-evaporation procedure, and the whole fabrication period only required 20 min. By changing X ions in the ZXO matrix framework, linear tunable photoluminescence was successfully realized. A sample with a mixed phase of ZnAl 2 O 4 and ZnCr 2 O 4 (ZACO) was also prepared using the same method, and ultrabroadband emissions ranging from 1050-1550 nm were detected. It is valuable to further explore the combinations based on these frameworks to realize tunable emission spectra. Fundamental research on the physical processes will open a new gateway for further research of TMI-doped nanocrystals with promising luminescence properties and broaden the applications to a variety of areas, especially in the biomedical field.
研究领域:
材料科学
·
光学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
Advanced Materials Technologies
·
2022
·Vol. 7
·期 11
·2200320
·
IF 8.856
Shihai Miao,Yanjie Liang,Yan Zhang,Dongxun Chen,Xiao-Jun Wang
Blue light-emitting diode (LED) pumped short-wave infrared (SWIR; 900–1700 nm) emitters are providing new solutions in the design of portable and cost-effective infrared light sources for medical, surveillance, and spectroscopy applications by taking advantage of converter technology. However, desirable blue-light-excitable SWIR-emitting phosphors with a peak wavelength longer than 1000 nm are lacking. Herein, a promising broadband SWIR phosphor is designed and developed by incorporating Cr 3+ -Ni 2+ ion pairs into LiMgPO 4 host. Upon 450 nm blue light excitation, the as-synthesized LiMgPO 4 :Cr 3+ ,Ni 2+ phosphor exhibits a broad and intense SWIR emission spanning from 1100–1600 nm with peak wavelength at 1380 nm and a full width at half maximum of 273 nm due to the efficient energy transfer from Cr 3+ to Ni 2+ . Moreover, phosphor-converted SWIR LED prototype device based on the combination of 450 nm blue LED chip and the optimized phosphor is fabricated as a new type of broadband illuminator covering the SWIR waveband, delivering a maximum radiant power of ≈2.7 mW at 120 mA driving current. Benefiting from the distinct spectral characteristics of SWIR light, the practical relevance of the fabricated SWIR illuminator is demonstrated in covert information identification and night vision lighting.
研究领域:
材料科学
·
光学工程
·
光电子技术
✓ 已验证
DOI
高影响因子
Journal of Semiconductors
·
2020
·Vol. 41
·期 12
·122501
·
IF 0
Zhiguo Sun,Bo Cai,Xi Chen,Wenxian Wei,Xiaoming Li,Dandan Yang,Cuifang Meng,Ye Wu,Haibo Zeng
The possibility to induce a macroscopic magnetic moment in lead halide perovskites (LHPs), combined with their excellent optoelectronic properties, is of fundamental interest and has promising spintronic applications. However, these possibilities remain an open question in both theory and experiment. Here, theoretical and experimental studies are performed to explore ferromagnetic states in LHPs originated from lattice defects. First-principle calculations reveal that shallow-level Br vacancies in defective CsPbBr3 can produce spin-splitting states and the coupling between them leads to a ferromagnetic ground state. Experimentally, ferromagnetism at 300 K is observed in room-temperature synthesized CsPbBr3 nanocrystals, but is not observed in hot-injection prepared CsPbBr3 quantum dots and in CsPbBr3 single crystals, highlighting the significance played by vacancy defects. Furthermore, the ferromagnetism in the CsPbBr3 nanocrystals can be enhanced fourfold with Ni2+ ion dopants, due to enhancement of the exchange coupling between magnetic polarons. Room-temperature ferromagnetism is also observed in other LHPs, which suggests that vacancy-induced ferromagnetism may be a universal feature of solution-processed LHPs, which is useful for future spintronic devices.
研究领域:
材料科学
·
凝聚态物理
·
自旋电子学
✓ 已验证
DOI
JOURNAL OF WUHAN UNIVERSITY OF TECHNOLOGY-MATERIALS SCIENCE EDITION
·
2018
·Vol. 33
·期 3
·559-565
·
IF 0.524
Guo Huiling,Sun Honghao,Su Zhengding,Hu Shuchao,Wang Xiaotao
A facile approach has been developed to synthesize Fe 3 O 4 @PAM (polyacrylamide) nanoparticles (NPs) with carboxyl groups on the surfaces by copolymerization with acrylamide and acrylic acid in Fe 3 O 4 NPs aqueous suspension. Nitrilotriacetic acid (NTA) was conjugated to the magnetic NPs via well-known carboniimide chemistry using EDC and NHS. The Ni 2+ ions loaded on the surface of NPs provide abundant docking sites for immobilization of His-tagged green fluorescent proteins (His-tagged GFP). The high magnetic property of Fe 3 O 4 @PAM@NTA-Ni 2+ allows an easy separation of the NPs from solution under an external magnetic field, with high His-tagged protein binding capacity (42 μg protein/mg of NPs). The NPs can be recycled for at least four times without significant loss of binding capacity to proteins. These materials show great potential to separate His-tagged protein with low-cost purification at industrial scale.
研究领域:
材料科学
·
生物化学
·
生物技术
·
纳米技术
✓ 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）