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  • Overview
    DONG Wenlong, LIU Luqi
    Chinese Journal of Light Scattering. 2021, 33(1): 1-15.
    Two-dimensional (2D) materials, with remarkably electronic, optical, and thermal properties, have attracted tremendous attention in recent years. To meet the rapid development of 2D materials, it's fundamentally necessary to the precisely characterize the structure and properties of 2D materials. Raman spectroscopy has been proven to be a fast, convenient, and nondestructive technique to characterize the basic structural information of low dimensional materials. In this review, we introduce recent advances in Raman spectroscopy for structural characterization of 2D materials. We mainly focus on the characterization of layer number, stacking order, crystalline orientation, defects, and structural phase transition of 2D materials by Raman spectroscopy.
  • The Journal of Light Scattering. 2018, 30(3): 197.
    Based on discrete dipole approximation (DDA), the effect of peak value and the peak position of optical absorption spectrum of Au@Ag core-shell nanostructure was systematically studied by the factors such as shell material, size and morphology. The results show that the calculations of Au spherical nanoparticles in the liquid environment are in agreement with the results calculated by the Mie theory, indicating that the optical properties of the Au@Ag core-shell nanoparticles after the cubic spline interpolation of the optical constants are accurate and reliable. With the increase of Ag shell thickness, the absorption spectrum of Au@Ag core-shell spherical nanoparticles forms different acromion with the spectrum of gold spheres, then the main peak shifts to red and the blue-shift of acromion vanishes,which becomes an optical absorption peak, and the intensity of optical absorption peak is enhanced. The optical absorption spectra of Au@Ag core-shell nanocube shows many secondary absorption peaks at <450nm. With the growth of Ag shell thickness, the primary and secondary absorption peaks enhance, and the main absorption peak shows obvious blue-shift. The Ag shell not only changes optical absorption intensity and the location of peak value, but also forms strong surface plasma resonance (SPR) at the tip of Au@Ag core-shell nanoparticles, and improves the effect of Ag on optical absorption.
  • Papers by young scholars at the21th National Conference on light scattering
    ZUO Jiaqian, WANG Yukai, WANG Hongqiu, GENG Lin
    Chinese Journal of Light Scattering. 2022, 34(1): 1-5.
    Raman spectroscopy has been widely used in chemical industry, security,anti drug and other industries and research fields, but the traditional Raman spectroscopy analysis technology relies on the spectral database, through the spectral feature extraction for identification. Feature extraction is the key step of Raman recognition. Principal component analysis, factor analysis and other methods are usually used for feature extraction, and then KNN, SVM and random forest methods are used for qualitative identification of spectral features. When there is no undetermined substance in Raman database, it is easy to cause the wrong classification of the substance to be detected. In order to solve this problem, a method based on convolution neural network is proposed to identify the lack of substance spectrum in database. In the process of the experiment, we use nine categories, more than 200 kinds of psychotropic drugs Raman spectrum as the test object, through the construction of convolution neural network automatic feature extraction, and use softmax classifier to analyze more than 200 kinds of substances according to nine categories, such as amphetamine, cathinone, cannabinoids and so on. Compared with the traditional machine learning methods such as  k nearest  neighbor and support vector machine, the accuracy of model recognition based on convolution neural network is significantly improved. This method can provide a new recognition method for Raman spectrum database.
  • Surface-Enhanced Raman Scattering (SERS)
    SI Lifang, FAN Xingce, HOU Xiangyu, LI Guoqun, LONG Kailin, LUO Xiaoguang, NI Zhenhua, QIU Teng
    Chinese Journal of Light Scattering. 2021, 33(1): 32-39.
    Some metal oxides possessing surface-enhanced Raman scattering (SERS) ability have drawn tremendous attention recently for their good signal uniformity, chemical stability and biocompatibility. However, most of them present deficient Raman enhancement factors which cannot meet the rigorous requirement in SERS applications. It is desirable to develop efficient approaches to promote the SERS performance. The different inherent features of metal oxides compared with noble metals, endow the former abundant possibilities to tailor SERS performance, such as tailoring of bandgap, stoichiometry or excitons. The effective tailoring of several inherent properties of metal oxides simultaneously may contribute synergistically to the overall SERS performance. Therefore, we choose indium tin oxide (ITO) as an example to explore the possibility to integrate its inherent SERS-activity with its optical interference cavity, to further promote the SERS performance. This work demonstrates a synergistical approach to engineer the SERS-active metal oxide substrate, providing a general concept to manage the intrinsic SERS ability of metal oxide together with optical interference effect.
  • The Journal of Light Scattering. 2018, 30(3): 203.
    The LSPR spectroscopy of Ag nanoparticles is sensitive to the changes of surrounding medium, which enables the nanoparticles to serve as plasmonic nano sensors. In this paper, the spectroscopy and sensing performance of nanosphere are investigated by employing the Mie theory in absorbing medium. The results show that when the imaginary part of the complex refractive index of the medium is small, its influence on the LSPR spectroscopy and the sensing performance can be neglected; The LSPR spectroscopy changes greatly, and the sensing performance of nanosphere decreases with the increase of the imaginary part. The LSPR peak disappears when the imaginary part of surrounding medium is large enough, then LSPR spectroscopy is not suitable for sensing.
  • Surface-Enhanced Raman Scattering (SERS)
    ZHANG Feng, TAO Yu, TANG Qiqi, WU Binbin, LIU Shan, LEI Li
    Chinese Journal of Light Scattering. 2021, 33(1): 40-44.
    As a wide-band gap (Eg=4.8 eV) semiconductor, the phase stability and lattice dynamics about the Ga2O3 under high pressure provide us the valuable information for its applications. However, the lack of the study on the phase stability and the lattice dynamics of Ga2O3 under high pressure makes the phase transition point remains controversial. In this work, we find that the irreversible βα phase transition occurs at 20.1-22.7 GPa by using the high-pressure Raman scattering based on diamond anvil cell (DAC). We also provide the Grüneisen parameter and pressure coefficient of α-Ga2O3 and β-Ga2O3. Our results also suggest that the pressure coefficient of β-Ga2O3 exhibits anharmonic properties.
  • The Journal of Light Scattering. 2016, 28(2): 144-148.
    Pure ZnO ceramics and GZO (Ga:ZnO) ceramics were prepared by solid phase reaction method. We measured GZO ceramics with different Ga concentration by Raman spectroscopy and X-ray diffraction, and studied the variation of Raman spectra of the samples. The results showed that pure ZnO and GZO ceramics were maintained a hexagonal wurtzite structure. E2(low) and E2 (high) who were the characteristic bands of ZnO were found in 98 cm-1 and 437 cm-1, respectively. There appeared new bands at the 584 cm-1 and 631 cm-1 in the Raman spectra of GZO ceramic. And the band at around 1148 cm-1 corresponding to an overtone of E1(LO) mode has also undergone some changes with the increasing of Ga doping concentration. We assigned the vibration mode of the new band and the change of the original band after doping, which for 631 cm-1,we believed that this band is attributed to the local vibration mode that the substitution of Ga for Zn with O. (LVMGa-O) .
  • The Journal of Light Scattering. 2016, 28(2): 125-130.
        Cubic (3C)-SiC films were grown on Si (100) substrate by chemical vapor deposition (CVD). The microstructures and optical properties of 3C-SiC films have been studied by spectroscopic ellipsometry (SE) and Raman scattering. Raman scattering and SE were used to characterize 3C-SiC materials. From the analysis of SE we can obtain thickness of 3C-SiC films. Also from the analysis of Raman spectra, we can see the line shape of TO mode and LO mode from the fitting result, and the correlation length and carrier concentration were obtained. The result of correlation length reveals that the crystalline quality is expected to improve with film thickness increasing and Raman scattering spectra also shows the effects of the epilayer thicknesses.
  • The Journal of Light Scattering. 2016, 28(3): 203-208.
    The prepared silver nanoparticles synthesized by chemical method was bound with lysine at different pH values. The UV-Vis spectrum and dynamic light scattering methods were used to study the stability of Ag colloids and AgNPs-lysine system. The interaction of Ag nanoparticles and lysine was surveyed by SERS. The results showed at the pH value of 5~10, the UV-Vis spectra appeared strong adsorption peak, the particle size was uniform distribution and DLS intensity auto-correlation curve was smooth, which indicated that the system had good stability. The interaction of lysine binding to Ag nanoparticle surface was investigated by SERS. At the pH value of 4, the SERS band at 1440 cm-1 is assigned to δ (NH3+), and the band of 1576 cm-1 is assigned to δ (COO-) , which tells the lysine adsorbs on the Ag sruface through the interaction of the amino and carboxyl groups together. At the pH value of 10, the main characteristic Raman spectrum was δ(COO-)at 1576 cm-1, it demonstrated that the lysine was adsorbed on the surface of silver nanoparticles with the NH3+ group.
  • The Journal of Light Scattering. 2016, 28(1): 84-90.
       Using Fourier transform infrared (FTIR) spectroscopy of three willow leaf and leaf disease, the young leaves of the same branch and leaves, yellow leaves, leaf disease spectrum testing, aims to analyze the willow leaf disease of some physiological changes, to explore the effect of disease leaves on the clustering of the system. Infrared spectroscopy blade at different stages of major change in 1800~ 800 cm-1, this bands second derivative processing, you can clearly see the superimposed region of the protein and lignin 1700 ~ 1500 cm-1, characteristic peaks of calcium oxalate 1621,1318 cm-1, characteristic peaks carbohydrate peak near 1075 cm-1 strong there are significant changes, with absorbance ratio A1621 / A3390, A1318 / A3390, A1075 / A3390 to compare the relative content of calcium oxalate and sugar, with 1700 ~ 1500 cm-1 band fitting peak area ratio S amide I /S lignin, S amideⅡ/S lignin and S amideⅡ/S amide I used to compare the relative amounts of the protein. The results showed that the relative contents of calcium oxalate in the diseased leaves were increased, and the relative contents of polysaccharide and protein decreased. The blade 1800 ~ 800 cm-1 range of the second derivative of systematic cluster found diseased leaves change did not affect the chemical composition of the clustering effect, clustering correct rate of 100%.
  • GU Zi-heng, ZANG Qiang, YE Jing-fei, ZHENG Gai-ge
    Chinese Journal of Light Scattering. 2022, 34(2): 116-120.
    The interactions between visible light wave and the prism-coupled multilayer optical film has been studied based on the transfer matrix method (TMM). A bandpass filter due to resonance tunneling is realized. The transmission spectrum of the composite structure is calculated, and the influence of the thickness of the air gap between the prisms on the filtering characteristics is analyzed. Under the incident light of transverse electric (TE) wave, the geometric parameters corresponding to the designed color are obtained through optimization calculation. Unlike the color filter in reflection mode, the proposed structure transmits a specific color and reflects the rest of the spectrum. After optimization, the structural parameters correspond to the red, green and blue (RGB) three-color filters are obtained with 100% high transmittance. The filter resonance wavelengths for red, green, and blue are 683 nm, 517 nm, and 444 nm, respectively.
  • JIANG Wen-ping1,WU Qi-xin2,MIN Jun,DAI Cui-xia*
    The Journal of Light Scattering. 2020, 32(3): 195-201.
    Photoacoustic imaging is a non-invasive 3D imaging technique which has been developing rapidly in recent years. It combines the high contrast characteristics of pure optical imaging with the high penetration depth characteristics of pure ultrasonic imaging. It provides an important means to study characteristics of biological tissues. In this paper, the principle of photoacoustic imaging technology and method and situation of photoacoustic imaging in biomedical application .
  • Tu Zhengqian1*, Dong Lichao3, Zhao Dongfeng3, Feng Di2, Wang Shenze1
    The Journal of Light Scattering. 2020, 32(3): 245-250.
    This paper analyzes the scattered light intensity of three types of defects commonly encountered in glass wafer processing: particle defects, bubble defects, and triangular scratches. It is found that different defect structures have different scattered light in space. The strong distribution feature can establish the correspondence between the defect structure and the spatial distribution of scattered light intensity. At the same time, for the micron-scale defects on the wafer surface in the production line, the scattered light intensity of different size particle defects is calculated, and the micron-scale defect size is obtained. Therefore, a non-imaging defect detection method is proposed: detecting the scattered light intensity value and spatial distribution of the acquired defect, determining the defect structure by using the spatial distribution structure of the scattered light, and calculating the defect size by using the scattered light intensity, thereby indirectly determining the defect information, and achieving the purpose of defect detection.It can provide a methodological reference for rapid detection of defects in the wafer industry application process.
  • The Journal of Light Scattering. 2016, 28(4): 317-323.
     In this paper, the solid-solution series of the jarosite group AFe3(SO4)2(OH)6 have been synthesized, where the site of A can be occupied by K+, Na+ and H3O+. In addition, nearly fully occupied potassium jarosite is prepared for comparison. Raman spectra of the jarosite group are measured and analysized. The jarosite group minerals can be characterized by Raman spectra and the bonds can be due to the hydroxyl groups, internal modes of sulfate and lattice modes. Some bonds assignment which are open to question are analysized. According to the number of the scattered peaks and frequencies, the size of the ionic radius, bonds length and bonds angle, the effect of the substitutions of ions in A-site of jarosite solid solution series is analysized by hooke's law.  The substitution effect of A position ion mainly affect the OH in the jarosite and the hydroxyl vibration mode.
  • The Journal of Light Scattering. 2016, 28(1): 91-96.
       Hole conduction layer is one of the most important part in organic solar cells. In this study, we prepare a macromolecular composite film suitable for hole conduction in an organic solar cell using layer-by-layer (LbL) deposition technique and low conversion temperature process under ambient conditions. As opposed to previous processes, our method not only supplies a controllable layer thickness but also provides a better electric property. An UV-Vis spectrometer is used to verify our results. It shows that low temperature conversion process under ambient condition works just the same as traditional high temperature conversion process under vacuum conditions. Low-temperature conversion process causes fewer damages on the structure of the macromolecule and raises hole mobility from 10-6 cm2/Vs to around 10-5 cm2/Vs.
  • The Journal of Light Scattering. 2016, 28(1): 1-5.
       通过块状材料溶解(BMD)方法合成了形貌规整的BiVO4单晶样品。利用原子力显微镜联用的共焦拉曼光谱借助表面等离子增强效应从微纳尺度研究了单斜层状BiVO4 {011}和{010}晶面光催化降解行为的反应动力学过程差异,发现在{011}晶面上光催化的降解速率常数是{010}晶面的2倍。另外,光氧化探针辅助的单粒子荧光成像进一步佐证了该结果,荧光探针分子在光激发下主要在{011}晶面上被氧化。
  • The Journal of Light Scattering. 2018, 30(1): 6-9.
    The intensity-weighted average particle size and intensity-weighted particle size distribution (PSD) can be obtained by the dynamic light scattering. To get the number-weighted PSD or volume-weighted PSD from the intensity-weighted PSD, the intensity scattered by particles of different size must be taken into account. The light intensity scattered by particles of different size is calculated using Mie scattering theory. Then, the number-weighted PSD can be calculated from the intensity-weighted PSD by dividing by the scattering intensity of the particle with the corresponding size. To demonstrate this the intensity-weighted PSD of the mixed polystyrene latex particles is obtained by dynamic light scattering, and the intensity-weighted PSD is converted to number-weighted and volume-weight PSDs using this method. Scanning electron microscopy is used to get the true number-weighted PSD to compare with our results. Comparison of the two number-weighted PSDs shows that accurate number-weighted PSD can be obtained by using approach outlined.
  • CHEN Zujie, CHEN Xi, QIN Hao, TIAN Youwei
    Chinese Journal of Light Scattering. 2022, 34(2): 121-126.
    A single-electron collision model is established according to the laser-electron interaction equation and the electron radiation power equation, and the three-dimensional spatial distribution characteristics of the electron oscillation radiation under the action of circularly polarized tightly focused laser pulses of different intensities are studied in detail with the help of MATLAB software simulation. The results show that the spatial radiation maximum of the colliding electrons increases with the increase of the laser intensity. From the three-dimensional spatial image characteristics, with the increase of laser intensity, the three-dimensional angle enclosed by the radiation cone surface expands continuously, when the amplitude peak from linear to nonlinear transition, the radiation value in the direction of the polar angle changes from smooth to appearing ripple, and the azimuthal direction changes from uniform to nonuniform, when the normalized laser intensity reaches 10, the radiation direction is approximately perpendicular to the direction of motion in a plane.
  • The Journal of Light Scattering. 2016, 28(1): 16-22.
  • The Journal of Light Scattering. 2016, 28(2): 163-167.
    In the paper 3 kinds of animal for a total of 30 animal blood samples and 21 human blood samples were chosen as the typical tested objects. Principle component analysis (PCA) method was employed to quickly identify the species of blood samples based on Raman spectroscopy. Vector normalization was used to preprocess the Raman spectroscopy signal. According to the plot of Leverage value vs. Studentized residue, outlier sample was detected and removed. By the PCA method, the correct rate between animal blood samples and human blood samples was up to 95% based on PC1and PC2. Further on the basis of PC4 and PC5, the correct rate of identification the animal blood sample was above 90%. The experiment results showed that the PCA method had good application prospects and feasibility to identify the species of blood samples. This method provided a reference for processing the similar problems in the field of forensic science and life science.
  • The Journal of Light Scattering. 2018, 30(3): 209.
    Surface-enhanced Raman scattering (SERS) can paves the way for the trace detection of low-concentration analyses, even single molecular detection, and owns greatly potential application prospect in chemistry, biology, environment, and so on. Development of high-performance SERS substrate is one of the most import research topic in SERS technology. In this work, we achieve the fabrication, characterization, and SERS effect research of a kind of high-performance, low-cost, and large area SERS substrate. The Raman scattering intensity from R6G molecule can be effectively enhanced by this SERS substrate for about five times when compared with that with roughness Au film. We carry out systematic numerical simulation and experiment research on the influence of micro-sphere diameter and nano-particle height on the Raman scattering enhanced factor, and find an optimized structure parameters. Our work will provide a kind of high-performance SERS substrate.
  • The Journal of Light Scattering. 2016, 28(2): 106-111.
      This article introduced a filter paper-based SERS substrate through soaking method, and investigated the relationship between the distributions of silver nanoparticles (AgNPs) on the filter paper with soaking time in detail. SERS spectra of seminal plasma under different excitation wavelengths (514 nm and 785 nm) were compared, and the latter was confirmed to demonstrate better SERS signals. SERS and normal Raman spectra of seminal plasma using 785 nm excitation laser was compared as well. More importantly, the intensity of the strongest peak (654 cm-1) from SERS spectra of seminal plasma was used to evaluated the enhancement effects and signal reproducibility with filter paper SERS substrates under different soaking time(6 h,12 h,24 h). Our results indicated that the AgNPs on the paper substrate soaked with concentrated AgNP colloid presented a relatively uniform distribution at the soaking time of 12 h and the substrate demonstrated high Raman signal enhancement and good signal reproducibility as well.
  • Surface-Enhanced Raman Scattering (SERS)
    WANG XiaoAn, SHEN Wei, YU Daoyang, DONG ronglu, TANG Xianghu
    Chinese Journal of Light Scattering. 2021, 33(1): 24-31.
    In this article, the comparative study of surface-enhanced Raman scattering (SERS) performance of assembled Au nanorods (AuNRs) and Au nanodumbbells (AuNDs) based on capillaries was introduced. Under the same conditions of the synthetic precursor and the dispersed system, two kinds of nano units were assembled on the inner wall of capillaries based on the same surface ligand exchange treatment process and the same assembly technology. And the AuNDs assembly structures based on capillary (AuNDs/cap) showed more significant SERS activity. Meanwhile, the uniform and reproducibility of the two assembly structures were pretty much the same. Furthermore, the AuNDs/cap structures can be used for sampling and SERS detection of malachite green (MG) down to 2×10-3μg/g levels in real water samples, which exhibit an excellent practicability and a great promise for rapid and credible practical detection.
  • The Journal of Light Scattering. 2018, 30(3): 284.
    Raman scattering and Brillouin scattering are two phenomena, which are most representative  in the inelastic light scattering, they were named by using C. V. Raman and L. Brillouin who are Indian and American of France descent scientists, respectively. The cognition (including phenomena, theory and their applications) of the former is more deepen than the latter, for people. Therefore, L. Brillouin and Brillouin scattering will only have been given more details in this summarize.
  • The Journal of Light Scattering. 2016, 28(1): 6-11.
           使用共焦显微拉曼光谱仪,结合表面增强拉曼散射(Surface-Enhanced Raman Scattering ,SERS)技术,采集含有农药马拉硫磷和二嗪农的苹果汁样本的基于银纳米溶胶的表面增强拉曼光谱,采用距离匹配和判别分析的方法对其进行定性分析。然后结合偏最小二乘(Partial Least Squares ,PLS)方法对两种农药的表面增强拉曼光谱分别进行数学建模分析。结果表明表面增强拉曼散射(SERS)技术对无损快速定性分析马拉硫磷和二嗪农具有较高的准确性,而定量分析二者的含量也具有较高的可行性。
  • The Journal of Light Scattering. 2017, 29(4): 309.
    The SERS detection of organophosphorus pesticide ethyl paraoxon and organochlorine pesticides r-666 were achieved by the high-density Au-Ag alloy nanourchin as SERS substrate. The Ag nanoparticles were synthesized firstly, then L-dopa was used to reduce the Ag nanoparticles, and ultimately the formation of Au-Ag alloy nanourchin structure. Using this high density tipped structure as the SERS substrate to detect the organophosphorus pesticide ethyl paraoxon and organochlorine pesticides r-666 on the portable Raman spectrometer, and the results showed high sensitivity. Therefore, our platform for the detection of pesticide residues provide a simple, convenient and high sensitivity method.
  • HAN Qirui, KANG Mingliang, CHEN Xuebing, ZHANG Jing
    Chinese Journal of Light Scattering. 2022, 34(2): 127-133.
    In this paper, the tungsten oxide photocatalysts with monoclinic/hexagonal phase junction structure (m/h-WO3) were synthesized from in situ growth of monoclinic tungsten oxide on the surface of hexagonal tungsten oxide by hydrothermal method when the sodium tungstate dihydrate was used as the main raw material. The results of XRD, Raman and SEM characterization demonstrate that the composition controll of the m/h-WO3 phase junction structure can be realized by adjusting the concentration of the reaction solution. The experimental results of photocatalytic degradation of Rhodamine B under visible light show that compared with pure phase h-WO3 and m-WO3, m/h-WO3 phase junction structure has better photocatalytic properties. The composition of hexagonal phase and monoclinic phase in m/h-WO3 phase junction is one of the main factors affecting photocatalytic performance. The 5% m/h-WO3 phase junction sample has exhibited remarkable photocatalytic activity, and the degradation rates were 7.6 and 5.0 times than that of h-WO3 and m-WO3 samples, respectively. SPV test results show that m/h-WO3 phase junction structure, especially with a suitable crystalline phase composition, can significantly improve the separation efficiency of photogenerated electrons and photogenerated holes, thus improving the photocatalytic performance of the photocatalysts.
  • The Journal of Light Scattering. 2016, 28(1): 45-50.
  • The Journal of Light Scattering. 2016, 28(1): 12-15.
  • The Journal of Light Scattering. 2016, 28(4): 293-296.
    Silver nanoparticles were prepared as SERS substrate to test BPA. Coagulator-NaCl was added to study the effect on SERS. The results showed that obvious SERS signal was gotten while the concentration of BPA in ethanol was as low as 10-7 g/mL. And due to the simple procedure in sample preparation and pretreatment, this method shows great application potential in rapid test for BPA.
  • The Journal of Light Scattering. 2016, 28(4): 297-301.
    The drugs was rapidly separated and purified in human urine sample by pretreatment. Furthermore, the self-assembled gold nanorods were used as the substrate to detect the drugs in real purifiedhuman urine byportable Raman spectrometer. It was found that our substratepresent excellent sensitivity of methamphetamine (MAMP), 3,4-methylenedioxy-methamphetamine (MDMA) and methcathinone(MCAT) detection.The whole process of the purifiedand detected procedurecan be completed in ~3.5 min.Therefore, our platform for detecting drugs promises a great prospective towards a rapid, reliable and on-spot detection method.
  • The Journal of Light Scattering. 2016, 28(2): 168-174.
    Supported planar lipid bilayers are artificial lipid bilayer membranes. Surface structures and properties of the solid substrates can affect the formation process, fluidity, two-dimensional structure and chemical activity of the SPBs, then affect properties of protein. Even on mica and SiO2 surfaces, which are flat and biologically inert, and most widely used as the substrates for the supported lipid bilayers, cause differences in the structure and properties of the supported membranes. In this review, by performing Raman spectroscopy, we analyzed the conformation of SPBs at mica and SiO2. Futhermore, we added the monomer amyloid-beta peptides onto SPBs. The differences between the conformation of amyloid-beta at mica and SiO2 are shown by Raman spectroscopy with different incubation time.
  • The Journal of Light Scattering. 2016, 28(1): 42-44.
          水热法合成祖母绿的化学成分、晶体结构和宝石学性质与天然祖母绿相似,常规宝石学检测项无法有效区分。合成祖母绿的生长环境比天然祖母绿理想,其晶格应力较小,相应的声子寿命较长,对应的拉曼谱峰线宽较窄,因此拉曼光谱半高宽可提供祖母绿是天然或合成的信息。本论文使用德国布鲁克Senterra型激光拉曼光谱仪进行测试分析,发现天然祖母绿的半高宽均在8.5 cm-1以上,而水热法合成祖母绿均在8.5 cm-1以下。
  • The Journal of Light Scattering. 2016, 28(1): 27-41.
  • Other Optical Spectroscopic Techniques and Applications
    WANG Tao, ZHANG Huafang, MAO Yanli
    Chinese Journal of Light Scattering. 2021, 33(1): 93-100.
    Low-dimensional organic-inorganic hybrid perovskite materials have attracted extensive attention due to their exotic photoelectric performance. In this paper, different size (CH3NH3PbI3) MAPbI3 nanocubes were studied by using diamond anvil cell (DAC), under high-pressure conditions. And explored the regulation of the size effect on the the optical properties of MAPbI3 nanocubes under high pressure. The in-situ high-pressure UV-visible absorption and photoluminescence spectra showed that the band gap and optical properties of MAPbI3 nanocubes with two different sizes showed different changes. The band gap of small-sized MAPbI3 nanocubes decreases with the increase of pressure below 0.25 GPa, while for large-sized nanocubes, the band gap continues to increased with the increasing of pressure below 0.67 GPa. The in-situ high pressure Raman measurement and analysis showed that the size effect was related to the interaction between the octahedron [PbI6]4- and the organic cation CH3NH3+. The results provide a research basis for in-depth understanding the band gap regulation, optical properties and structural stability of low dimensional organic-inorganic hybrid perovskite nanocrystals, and it provides a research idea for improving the conversion efficiency of organic-inorganic hybrid perovskite cells.
  • The Journal of Light Scattering. 2016, 28(1): 51-55.
  • The Journal of Light Scattering. 2016, 28(2): 97-101.
         Graphene, a two-dimensional monatomic layer of carbon material, shows its weak absorptance of only about 2.3% in the visible and near infrared region. This dramatically limits its application in graphene-based solar cells and photon detection. In this letter, we propose a metal-dielectric periodic nanostructure to enhance the absorptance of graphene based on the magnetic resonances. Using finite-element method, we numerically simulated the effect of the structural parameters of the nanostructure on the absorptance of graphene layer. Our calculations show that the absorptance of graphene can be enhanced by about 4 times with specific structural parameters. Inductor-capacitor (LC) circuit model is applied to reveal the mechanism behind the absorption enhancement of graphene. The LC model succeeds in predicting the magnetic resonances, which are independent of the presence of the graphene. Our proposed nanostructure, which is easy for practical fabrication, is expected to have potential applications in the design of novel graphene-based optical and optoelectronic devices.
  • The Journal of Light Scattering. 2018, 30(3): 258.
    This paper mainly about that rapidly detecting the types and concentration of residual organic solvents in wastewater by portable Raman spectrometer. Firstly, using a portable Raman spectrometer to establish a standard Raman spectrum. Then, using the same portable Raman spectrometer to test wastewater samples and comprising with the standard spectrum. Finally, the organic solvent types and concentration in wastewater were calculated. This is a simple, sensitive and rapid method and it is of great significance for monitoring the let out of wastewater in real time.
  • The Journal of Light Scattering. 2017, 29(4): 314.
    In this paper, a novel magnetic responsive photonic hydrogel was prepared by embedding monodisperse Fe3O4 colloidal particles into network of agarose matrix, and its optical properties was investigated. First, carboxyl decorated Fe3O4 colloidal particles were synthesized through a hydrothermal method. Then the Fe3O4 colloidal particles were dispersed in water to form homogeneous colloidal solution. After mixing the colloidal solution with agarose monomer and then complete cross-linking polymerization, a uniform composite agarose hydrogel containing Fe3O4 particles can be obtained. With large pore size of agarose gels, the Fe3O4 particles in agarose matrix are still movable and colloidal crystal arrays can be achieved under external magnetic field. Moreover, the structural color of the gel can be tuned continuously by changing the strength of magnetic field. As-prepared photonic hydrogels, with dynamically tunable structural colors, provide great opportunities for applications of colloidal photonic crystals.
  • CAO Wenzheng, He Shanshan, Teng Yajun, ZU Endong
    Chinese Journal of Light Scattering. 2022, 34(4): 290-295.
    sapphire are beloved as precious colored gemstones, With the continuous development of gemstone synthesis technology, there are many synthetic sapphire made by different synthetic methods on the market. Conventional gemological identification cannot simply and accurately distinguish natural sapphire from synthetic sapphire made by different synthetic methods. The thesis uses UV-Vis-NIR spectrometer to perform spectral analysis on sapphire. It is found that natural sapphire has The absorption peaks at 387 nm, 452 nm and 566 nm are absent from the synthetic sapphire synthesized by Czochralski method, flame melting method and Paulson method. Both Czochralski and flame melting sapphire have an absorption band around 600 nm; the Paulson sapphire has an absorption peak around 660 nm, and the other three types of sapphire have no such absorption peak. According to characteristic peak fitting analysis by Raman spectrum and spss one-way ANOVA analysis, it is found that there are significant differences in the full width at half maximum between natural sapphire and synthetic sapphire, the full width at half maximum of natural sapphire are greater than 10.0 cm-1,and the full width at half maximum of three synthetic sapphires are less than 10.0 cm-1.The full width at half maximum of the sapphire synthesized by the Paulson method is concentrated around 8 cm-1, while the half width of the sapphire synthesized by the flame melting method is generally 8 cm-1~10 cm-1, and the half width of the sapphire synthesized by the Czochralski method is distributed in 6 cm-1~8 cm-1 range .By comparing and studying the significant differences in spectral characteristics of UV-Vis-NIR spectra and Raman spectra, it can be use to distinguish and identify between natural sapphire and sapphire synthesized by different methods in a simple, effective and non-destructive manner.