JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2019
·
IF 6.361
Xia Zhang,Daolei Wang,Xiaokun Man,Jiang Wu,Qizhen Liu,Yongfeng Qi,Zhiqiang Liu,Xiaoyan Zhao,Jiaxi Wu,Chenyu Hao
The morphology of catalyst is a very important factor influencing the photocatalytic activity of the catalyst. Owing to its scientific and technological importance, controllable preparation of photocatalysts with different morphologies has been studied. In this work, BiOIO 3 /g-C 3 N 4 heterojunction composites are synthesized using hydrothermal method and the composites with different morphologies are fabricated by adjusting the amount of NaOH in precursor solutions to control the growth of BiOIO 3 crystal plane. The physicochemical properties of BiOIO 3 /g-C 3 N 4 heterojunction composites were investigated by XRD, XPS, FTIR, SEM, TEM, HRTEM, BET, UV–vis DRS and PL characterization. The effect of the BiOIO 3 morphology on the photocatalytic efficiency of BiOIO 3 /g-C 3 N 4 heterojunction composites was evaluated by photocatalytic removal of gas-phase Hg 0 under visible light irradiation. When the morphology of BiOIO 3 is regular square-like, BiOIO 3 /g-C 3 N 4 has the optimal removal efficiency 92.6% of Hg 0 . Finally, electron-hole migration path and photocatalytic mechanism of catalysts are proposed.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CRYSTENGCOMM
·
2017
·Vol. 19
·期 26
·3600-3606
·
IF 3.474
Suli Wu,Xiaoqian Sun,Zhipeng Meng,Shufen Zhang
Doping, incorporating appropriate and functional atoms or ions into host lattices of colloid nanoparticles, is an important approach to modifying the shapes and sizes of nanoparticles and endowing them with new and useful properties. Herein, we demonstrate a “core–shell” synthetic strategy to control the shape of core–shell structured NaGdF4 upconversion nanoparticles (UCNPs) by introducing an impurity dopant in the core region. We introduced Cr3+ ions in the core region of NaGdF4 to synthesize “Jasminum sambac flower” shaped non-classic core–shell NaGdF4:Cr3+@NaGdF4:Yb3+,Tm3+ UCNPs. First of all, the effect of doping concentration on the shape of NaGdF4 core was investigated. Then, the core–shell strategy was applied to obtain a shape-controlled hierarchical nanostructure, and the effects of Cr3+ concentration on the phases, shapes and sizes of the products were investigated in detail. TEM images indicate that NaGdF4:Cr3+@NaGdF4:Yb3+,Tm3+ nanocrystals with Cr3+ concentration of 40–50% show highly uniform “Jasminum sambac flower” shaped structures. TEM images and XRD patterns of NaGdF4:Cr3+@NaGdF4:Yb3+,Tm3+ at different reaction times indicate that, initially, the flower shaped products are cubic phase and the size of the flowers is about 50 nm; with an increase of the reaction time, the cubic phase nanocrystals discompose to small ones and then transform to a bigger hexagonal phase “Jasminum sambac flower”. This “core/shell” doping strategy presents a general route to achieving controlled morphology in lanthanide-doped nanocrystal systems.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Micro & Nano Letters
·
2018
·Vol. 13
·期 10
·1443-1446
·
IF 0.841
Jin Li,Ben Ze Wu,Zhen Xiang Zhou
γ-Bi 2 O 3 powders were prepared from [Bi(NO 3 ) 3 ·5H 2 O] and NaOH through low-temperature liquid phase method at <90°C. This process featured low cost, simplicity and a normal pressure. Bismuth oxides were synthesised in large quantities in water systems. Morphology, structure and optical properties were characterised by X-ray diffraction, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and ultraviolet visible absorption spectrophotometry (UV–Vis). The SEM indicated that tetrahedral Bi 2 O 3 with the edge length of 1–5 μm was formed. The FTIR spectra show a chemical bond of Bi–O existed. Bi 2 O 3 presents the photo absorption properties from UV light region to visible light and the band gap of the Bi 2 O 3 is 3.0 eV.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Crystals
·
2023
·Vol. 13
·期 10
·1432
·
IF 2.7
Yuke Shen,Shuang Hao,Angqian Suonan,Yanxia Liu,Hangqi Li,Wei Ma,Lin Zhao,Yagang Zhang
Nano-micro calcium carbonate has a small particle size, uniform distribution, and good dispersion performance, offering great research value and development prospects. It has been widely used as a filler material for rubber, paper, ink, pigments, and coatings. Developing an efficient and controllable approach to preparing nano-micro calcium carbonate with adjustable morphology and controllable size has significant economic and environmental benefits. This study reports the controllable synthesis of nano-micro calcium carbonate meditated by additive engineering. The effects of various additives including inorganic acids, organic acids, alcohol, and surfactants on the particle size and morphology of the prepared materials were investigated. SEM, FT-IR and other characterization methods were used to analyze the prepared nano-micro calcium carbonate particle size, dispersion, and uniformity. The results showed that the particle size of calcium carbonate was 4~7 μm with a cubic structure. The particle size of calcium carbonate prepared by adding surfactant additives is in the range of 1~4 μm, and the crystal shape of calcium carbonate changes from calcite to vaterite after adding sodium dodecyl benzene sulfonate. With the aid of additives, the calcium carbonate particles dispersed more evenly. The mechanism of the controllable synthesis of nano-micro calcium carbonate mediated by additive engineering is elucidated and discussed. SDBS was found to be the best additive for preparing nano-micro calcium carbonate, and the synthesis conditions were explored and optimized.Keywords:calcium carbonate;additive;particle size and morphology;energy conservation
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Superconductivity and Novel Magnetism
·
2024
·
IF 1.6
Pi Siwen,Li Jie,Zhang Yingde,Zhou Weina,Shan Shuo,Zhao Xuan
Ce-substituted M-type Sr 1– x Ce x Fe 12 O 19 ( x = 0.00–0.08) ferrites were successfully synthesized via the ball milling method, and the sintering temperature at 1200 °C for 2 h. The synthesized materials were characterized by X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), and vibrating sample magnetometry (VSM). The elemental makeup of the samples was characterized by energy-dispersive spectrometry (EDS). The XRD results showed the crystal structure and purity of the samples. The FTIR spectroscopy indicated tetrahedral and octahedral tensile vibrations of M-type strontium ferrite at two characteristic peak bands of 554 and 454 cm −1 . The FESEM showed that Ce doping resulted in fine grains. The EDS indicated that Ce content increased with decreasing Sr concentration but that the concentrations of other elements remained basically unchanged. The mass ratio of Sr:Fe is calculated from EDS results and the measured Sr:Fe mass ratio is quite close to the mass ratio calculated from the reactants used to synthesize each sample. The VSM showed that at a Ce doping of x = 0.02, the coercivity of the samples reached the maximum, and the coercivity values and the saturation magnetization were 3878.25 Oe and 73.625 emu/g, respectively. And such high thermal stability further determines that Ce-substituted strontium ferrites have infinite potential in application fields (T = 450.2 °C).
研究领域:
材料科学
·
磁学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Yumin An,Zanchao Gao,Beibei Dong,Liguo Dong,Libin Zhao
The photocatalytic hydrolysis reaction primarily unfolds on the material's surface, making the material's morphology and microstructure critical for the catalytic efficiency of photocatalysts. In this paper, a formic acid-assisted melamine hydrothermal self-assembly method is explored to prepare g-C 3 N 4 photocatalysts with a unique morphology. The impact of sintering temperature on the morphology of the g-C 3 N 4 photocatalysts are explored and the effect of formic acid concentration on the XRD and FTIR was analyzed. Findings reveal that the g-C 3 N 4 nanostructures photocatalyst possesses fibrous tubular and nanosheet structures, boasting a heightened specific surface area (32.9 m 2 /g) and a more refined graphite-like crystalline framework. When synthesized with a 0.15 M concentration of formic acid, the g- C 3 N 4 nanostructured photocatalyst achieved a hydrogen production rate (1289.4 μmol h −1 g −1 ), which is approximately 4.8 times greater than that of bulk g-C 3 N 4 (264.7 μmol h −1 g −1 ). This work provides a simple method for preparing high-performance g-C 3 N 4 based photocatalysts for visible light hydrolysis hydrogen production.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2019
·Vol. 9
·期 5
·408
·
IF 3.444
Chao Wang,Wenchao Hua,Guangtao Chai,Chuanhui Zhang,Yanglong Guo
Co3O4catalysts of cube and sphere shapes were prepared by one-step hydrothermal synthesis with different controlled amounts of Co(NO3)2·6H2O and NaOH. The morphological effects on both physicochemical properties and catalytic activities of vinyl chloride oxidation were investigated by material characterization and performance evaluation. The obtained results showed that the morphology, resulting in the exposure difference of crystal planes, significantly affected the catalytic property. The catalytic activity for vinyl chloride oxidation followed a descending order of Co3O4cube (Co3O4-c) > Co3O4sphere (Co3O4-s) > Co3O4commercial (Co3O4-com). The cube-shaped Co3O4presented higher catalytic activity and stability than Co3O4spheres despite their similar crystallographic structures as well as physicochemical and redox properties. Accordingly, the different catalytic behaviors should be attributed to a morphological effect. The Co3O4cube with a preferential exposure of (001) plane presented higher abundance of surface Co2+cations and adsorbed oxygen species, which acted as the active sites responsible for the improvement of its catalytic activity.Keywords:Co3O4;morphological effect;crystal plane;catalytic oxidation;vinyl chloride
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS LETTERS
·
2014
·
IF 2.269
Fuyou Liao,Lili Zhao,Chunxue Zhai,Zhiyong Zhang,Xiaolei Ma
SrCO 3 particles were prepared at 450–600 °C by a simple solution method. The phase structure, morphologies and photoluminescence (PL) properties of particles were investigated. All of the as-synthesized samples are orthorhombic SrCO 3 phase. SrCO 3 particles are composed of fibers aggregates and have layered morphologies. When excited by an appropriate wavelength, a broad emission band can be observed in the samples ranging from ultraviolet to red light region. The PL properties of samples were significantly affected by the fibers. SrCO 3 particles with fine and short fibers structure have excellent PL properties. In our experiment, SrCO 3 particles synthesized at 450 °C exhibit the strongest PL properties.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2016
·
IF 1.207
Lei Yang,Yangyang Zhang,Hua Li,Hezhou Liu
Metallic bismuth crystal is one important and interesting semimetal that has attracted great attention owing to its unique thermal and electrical properties. Herein, we report a facile, green, cost-effective and sustainable solvothermal process using ethanol, glycol, isopropanol, phenylcarbinol as solvent and commercial Bi 2 O 3 as the starting material to produce high-purity metallic Bi with tunable morphologies on large scale. It is found that all alcohols are capable of reducing Bi 2 O 3 to Bi and the reducibility of glycol is proved to be the strongest. The highest purity of the resultant Bi is calculated to be 99.74%. What's more, the morphology of final Bi particles is controllable by adding various types and concentrations of additives. As a consequence, our work lays the root for the large scale solvothermal production of high-purity Bi particles with various regular morphologies.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2018
·Vol. 11
·期 6
·995
·
IF 2.467
Anquan Deng,Yufu Zhu,Xin Guo,Lei Zhou,Qingsong Jiang
TiO2micro-/nano-structures with different morphologies have been successfully synthesized via a hydrothermal method. The effects of the solvents on the morphology and structure of the obtained products have been studied. The objective of the present paper is to compare the photocatalytic properties of the obtained TiO2products. During the synthesis process, the tetrabutyl titanate and titanium (IV) fluoride were used as the titanium source. The obtained micro-/nano-structures were characterized by field-emission scanning electron microscopy, X-ray diffraction analysis, and nitrogen adsorption-desorption isotherms. The photocatalytic activity of the samples was evaluated by the degradation of Rhodamine B solution under simulated solar irradiation. It is found that the morphologies and structures of TiO2have a great influence on its photocatalytic activity. Compared with other samples, TiO2flower clusters assembled with nanorods exhibited a superior photocatalytic activity in the degradation of Rhodamine B.Keywords:TiO2;different morphologies;photocatalytic activity;formation mechanisms
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2017
·Vol. 135
·期 6
·45810
·
IF 1.86
Xianglong Li,Teng Hou,Yishen Lu,Bin Yang
In the present study, we provide a method for controlling the surface morphology of centrifugally spun starch-based fibers by adjusting the ratio of amylopectin/amylose in starches and combining with a hot blast temperature. The effects of hot blast temperature, amylopectin, and amylose on fiber surface morphologies are investigated. Scanning electron microscopy is used to characterize the morphology of the prepared fibers. The results show that fibers with burr-shaped nanostructures on the surface can be fabricated by adding amylopectin to starches and are promoted by increasing the hot blast temperature. However, amylose in starches plays the role of smoothing the fiber surfaces. X-ray diffraction reveals that the fibers are amorphous. Through Fourier transform infrared spectroscopy analysis, it was found that some physicochemical changes occur during centrifugal spinning. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 45810.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2023
·Vol. 13
·期 16
·2289
·
IF 5.3
Zhenyu Wang,Haizhen Ding,Xuefeng Liu,Jing Zhao
Semiconductor oxide gas sensors have important applications in environmental protection, domestic health, and other fields. Research has shown that designing the morphology of sensitive materials can effectively improve the sensing characteristics of sensors. In this paper, by controlling the solvothermal reaction time, a unique hexagonal flower-like structure of In2O3materials consisting of cuboid nanorods with a side length of 100–300 nm was prepared. The characterization results indicated that with the increase in reaction time, the materials exhibited significant morphological evolution. When the solvent heating time is 5 h, the flower-like structure is basically composed of hexagonal nanosheets with a thickness of several hundred nanometers and a side length of several micrometers. With the increase in reaction time, the apex angles of the nano sheets gradually become obtuse, and, finally, with the Ostwald ripening process, they become cuboid nanorods with side lengths of 100–300 nanometers, forming unique micro-flowers. Among them, the material prepared with a reaction time of 20 h has good sensing performance for NO2, exhibiting low operating temperature and detection limit, good selectivity, repeatability, and long-term stability, thus suggesting a good application prospect.Keywords:In2O3;micro-flowers;morphological evolution;NO2sensor;solvothermal
研究领域:
材料科学
·
环境科学
·
化学传感器
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）