Methods and Applications in Fluorescence
·
2017
·Vol. 5
·期 4
·045001
·
IF 2.656
Zhongchen Bai,Licai Hao,Zhaoling Huang,Shuijie Qin,Zhengping Zhang
We studied an enhancement effect of defect fluorescence of ZnSe quantum dots (QDs) on a heterojunction of ZnSe QDs and gold nanoparticles. The photoluminescence (PL) of Au/ZnSe heterojunction is excited by using a 150 nm diameter ultraviolet laser spot of a scanning near-field optical microscope. Owing to the charge transfer of photon-generated carriers from ZnSe QDs, the enhanced PL effect is observed, which results from the increase of the built-in electric field to hinder the electron transfer to gold nanoparticles and is trapped by the defect states of ZnSe QDs. The broadening of defect fluorescence spectra and the reduction of excitonic fluorescence in multi-heterojunction of ZnSe QDs and gold nanoparticles are also observed which is attributed to an increase of their contact areas. We believe that enhanced defect fluorescence method described in this paper have potential applications in forming uniform optoelectronic heterojunction in controlling and boosting fluorescent efficiency of weak PL devices.
研究领域:
材料科学
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光学
·
纳米技术
✓ 已验证
DOI
PubMed
高影响因子
OPTICAL MATERIALS
·
2021
·
IF 3.08
Tingting Li,Chengcheng Sun,Chang Xue,Yutao Jiang,Jian Zhang,Lijuan Zhao
Iron (Fe) doped ZnSe microspheres were fabricated by solvothermal method . X-ray diffraction (XRD), Raman analysis, Fourier transform infrared (FT-IR) spectra and X-ray photoelectron spectroscopy (XPS) results indicate that Fe 2+ cations were incorporated into the zinc blende ZnSe lattices successfully and uniformly distributed in sample. SEM images displayed that doping with Fe 2+ cations did not change the morphology of microspheres . The growth mechanism of Fe-doped ZnSe microspheres was proposed. The band gap increases and photoluminescence (PL) peaks in visible region show blue-shift as doping with Fe ions . In addition, a reduction in PL lifetimes in visible range was also observed, which may be due to the increase in non-radiative energy transfer between Fe 2+ doping in the ZnSe matrix. The 5 E↔ 5 T 2 transition of Fe 2+ in the 3.6–5.5 μm spectral range was observed in Fe-doped sample at low temperature.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
JOURNAL OF CRYSTAL GROWTH
·
2012
·
IF 1.726
Shenjie Li,Daocheng Pan
Cu 2 SnSe 3 nanocrystals with a metastable zincblende and wurtzite structure have been successfully synthesized. The crystal structures were confirmed by means of X-ray diffraction and selected area electron diffraction . The lattice mismatch between Cu 2 SnSe 3 and ZnSe is only 0.26%, thus homogeneously alloyed (ZnSe) x (Cu 2 SnSe 3 ) 1− x nanocrystals could be synthesized. The band gaps of nanocrystals can be tuned in a wide range of 2.75 to 0.92 eV; however the bowing parameter as high as 19.1 eV for alloyed (ZnSe) x (Cu 2 SnSe 3 ) 1− x nanocrystals was observed. These low cost and dispersible alloyed (ZnSe) x (Cu 2 SnSe 3 ) 1− x nanocrystals with a targeted band gap have a high potential in thin film solar cells.
研究领域:
材料科学
·
太阳能电池研究
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产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2013
·Vol. 15
·期 48
·10495-10499
·
IF 3.879
Shufang Kou,Tingting Yao,Xiaofeng Xu,Rui Zhu,Qing Zhao,Jian Yang
Successful doping of anisotropic semiconductor nanocrystals with impurities offers an effective pathway to manipulate their physical properties and enhance the application performances. However, such doping into anisotropic nanocrystals is seldom reported because it needs simultaneous controls in the crystal growth for a specific shape and composition engineering for transition-metal doping. Here, ultrathin Cu-doped ZnSe nanorods are synthesized by a growth–doping process. The doped nanorods are characterized by XRD and TEM techniques to reveal their crystal structure. Their optical properties are described in terms of UV-Vis absorption spectra and PL spectra. The tunable emission from 480 to 520 nm evidences the successful doping of Cu into ZnSe nanorods. The effects of the reaction time, the reaction temperature and the surface ligand on the optical properties are discussed in detail. After purification, the doped nanorods with a Cu/Zn ratio of 1% give a quantum yield of 7%. This emission could be retained for weeks in air, which is important for its future applications in many fields.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
ACS Nano
·
2022
·
IF 18.027
Nuoya Li,Xujian Chen,Jin Wang,Xinmeng Liang,Lintao Ma,Xiaolang Jing,De-Li Chen,Zhengquan Li
Utilizing sunlight to convert CO2 into chemical fuels could simultaneously address the greenhouse effect and fossil fuel crisis. ZnSe nanocrystals are promising candidates for photocatalysis because of their low toxicity and excellent photoelectric properties. However, pristine ZnSe generally has low catalytic activities due to serious charge recombination and the lack of efficient catalytic sites for CO2 reduction. Herein, a ZnSe nanorods–CsSnCl3 perovskite (ZnSe–CsSnCl3) type II heterojunction composite is designed and prepared for photocatalytic CO2 reduction. The ZnSe–CsSnCl3 type II heterojunction composite exhibits enhanced photocatalytic activity for CO2 reduction with respect to pristine ZnSe nanorods. The experimental characterizations and theoretical calculations reveal that the efficient charge separation and lowered free energy of CO2 reduction facilitate the CO2 conversion on the ZnSe–CsSnCl3 heterojunction composite. This work presents a type II heterojunction composite photocatalyst based on ecofriendly metal chalcogenides and metal halide perovskites. Our study has also promoted the understanding of the CO2 reduction mechanisms on perovskite nanocrystals, which could be valuable for the development of metal halide perovskite photocatalysts.
研究领域:
材料科学
·
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Inorganic and Organometallic Polymers and Materials
·
2011
·Vol. 22
·期 1
·27-31
·
IF 1.473
Wang Qun,Liu Futian,Jiang Qinghui,Sun Xuejiao,Wang Dongzhi
Fe 3 O 4 @SiO 2 @ZnSe composite nanoparticles with superparamagnetism and luminescence have been prepared by a facile chemical method. Nontoxic fluorescent ZnSe quantum dots were assembled around the Fe 3 O 4 -silica core–shell nanocomposite via chemical bonds formed between –COOH and –NH 2 . Transmission electron microscopy images show that the nanocomposites are approximately spherical and between 50 nm and 80 nm in size. The bifunctional nanocomposites exhibit superparamagnetic behavior and good fluorescence intensity. Magnetic attraction test, vibrating sample magnetometer at 300 K, UV–visible absorption and fluorescence emission spectroscopy were applied to characterize the magnetic/fluorescent properties of the nanocomposites.
研究领域:
材料科学
·
纳米技术
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART B-ENGINEERING
·
2019
·
IF 6.864
Fangxu Dai,Ruiyang Zhao,Xudong Huai,Jishu Han,Lei Wang,Shouhua Feng
Magnetic ZnFe 2 O 4 @ZnSe hollow nanospheres were fabricated by a two-step method and applied for visible light photocatalytic water splitting . Magnetic ZnFe 2 O 4 hollow nanosphere was prepared by using the carbonaceous microsphere as a template, and ZnSe nanoparticles were in site grown on the ZnFe 2 O 4 surface. Through optimizing the reaction time, ZnFe 2 O 4 @ZnSe hollow nanospheres exhibited efficient light absorption and improved photocatalytic performance, and ZnFe 2 O 4 @ZnSe-20 with suitable ZnSe shell thickness possessed highest hydrogen production amount in 6 h (16897.3 μmol/g). The experimental results revealed that the formation of heterojunction between ZnSe and ZnFe 2 O 4 effectively separated and transferred the photo-induced electrons and holes, and inhibited the electron-hole pairs recombination. In addition, the magnetic recyclability of ZnFe 2 O 4 @ZnSe hollow nanospheres was beneficial to further photocatalytic hydrogen production application.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH INNOVATIONS
·
2013
·
IF 0.321
Y. L. Ding,J. X. Bi,B. Du,X. Y. Hu,F. T. Liu
We have developed an aqueous synthesis for glutathione capped ZnSe nanocrystals. The structure and optical properties of the obtained ZnSe nanocrystals were characterised by X-ray diffraction, dynamic light scattering analysis, TEM, ultraviolet–visible, photoluminescence spectroscopy and Fourier transform infrared spectroscopy. The ZnSe shows a cubic zincblende crystal phase and has a narrow size distribution. Experimental results indicate that the pH value and reaction time play crucial roles in determining optical features. With the pH increasing from 10 to 12, and reaction time from 0 to 2 h, the fluorescence emissions of ZnSe nanocrystals are tuneable between 360 and 405 nm. The high quantum yields are calculated to be in the range of 0·3–22%. Furthermore, the luminescence intensity can be enhanced significantly when the nanocrystal sample is illuminated by room light. The mechanism for the resulting high quality optical properties is also elucidated.
研究领域:
材料科学
·
光化学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2023
·Vol. 17
·期 9
·1301-1310
·
IF 4.5
Wang Ying,Han Yue,Zhao Ruiyang,Han Jishu,Wang Lei
Photocatalytic hydrogen production utilizing abundant solar energy to produce high-calorie, clean, and pollution-free hydrogen is an important approach to solving environmental and resource problems. In this work, a high-efficiency flower-like ZnSe/Cu 0.08 Zn 0.92 S photocatalyst was constructed through element doping and the formation of a Z-scheme heterojunction. The synergistic effect of Cu doping and the built-in electric field in the heterojunction enhanced light absorption and utilization by the ZnSe/Cu 0.08 Zn 0.92 S microflowers, accelerated the separation and transfer of photogenerated electrons and effectively inhibited electron–hole recombination. Thus the photocatalytic hydrogen production ability of the ZnSe/Cu 0.08 Zn 0.92 S microflowers was increased significantly. The highly stable ZnSe/Cu 0.08 Zn 0.92 S microflowers could provide excellent catalysis of photocatalytic hydrogen production.
研究领域:
材料科学
·
环境科学
·
能源科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Zifan Zhu,Zheng Li,Xiaoyan Xiong,Xuqi Hu,Xinqi Wang,Nian Li,Tao Jin,Yufang Chen
Oxygen vacancies ZnO/ZnSe heterojunction was designed by incorporating ZnSe into ZIF-8 derived ZnO followed by an annealing process. The as-prepared material possessed excellent acetone sensing properties even at low concentrations and is expected to be used in the non-invasive detection of diabetes in patients. Using a facile hydrothermal method , pristine ZnO and ZnSe were prepared, and then they were mixed and thermally annealed to form the composite. Subsequently, the materials were characterized by using various techniques such as XRD, XPS , EPR, etc. According to the sensing study, the highest response of the material in 1 ppm acetone was as high as 5.8, which was 2.3 times that of pure ZnO. In addition, the as-prepared composite was less sensitive to interfering gases, which indicates the feasibility of developing highly sensitive acetone sensors based on this material. Thus, the material prepared in this work may be applied to the non-invasive detection of diabetes in patients, and hence it is worthy to conduct further in-depth research.
研究领域:
材料科学
·
医学传感器
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2020
·
IF 3.28
Chao Zhang,Tingting Li,Weijia Wen,Xiangdong Luo,Lijuan Zhao
Perovskite-semiconductor composites formed by high quality CsPbBr 3 nanocrystals embedded in ZnSe microsphere were prepared. The optical properties of pure CsPbBr 3 and composites were studied in detailed. Highly enhanced luminescence from CsPbBr 3 -ZnSe composites was observed and the excitation power-dependent photoluminescence of samples showed that the recombination in all samples involves excitons . The recombination lifetimes of composites for both fast and slow decays increased compared with pure perovskite, indicating that the nonradiative combination was suppressed which may be possibly due to the decrease of both bulk and surface defects , owing to the passivation of ZnSe. Besides, the visible light absorption range of composites was extended, which suggests increasing efficiency of photoelectric conversion and the utilization of sunlight.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2012
·Vol. 19
·期 5
·1732-1739
·
IF 5.925
Zhipeng Huang,Lei Pan,Peng Zhong,Maoying Li,Feng Tian,Chi Zhang
Graphical Bird on a quantum wire : Monodisperse Ag 2 S (or Ag 2 Se) ZnSe quantum wires can be synthesized at 120 °C with the assistance of Ag 2 S. These quantum wires are uniform in structure and morphology and have an aspect ratio of larger than 100. This method can be also used to fabricate CdSe quantum rods. A facile method for the low-cost and large-scale production of ultralong Ag 2 S (or Ag 2 Se) ZnSe quantum wires has been developed. ZnSe quantum wires (diameter≈4 nm) with high uniformity in their crystal structure and diameter can be synthesized by using a catalyst-assisted growth approach with Ag 2 S nanoparticles as a catalyst. The influence of the growth temperature, time, and type of catalytic particle on the morphology of the ZnSe quantum wires was systematically explored. Besides Ag 2 S, Ag 2 Se nanoparticles can also be adopted as the catalyst for the growth of ZnSe wires. This method can also be applied to the fabrication of uniform CdSe nanorods. This method is convenient for the controllable fabrication of metal selenides and is of importance for exploring fundamental nanoscale semiconductor physics, as well as for affording technological devices with optimized characteristics.
研究领域:
材料科学
·
纳米技术
·
半导体物理
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）