Progress in Natural Science-Materials International
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2020
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IF 4
Zemin Zheng,Yiming Cao,Zhe Li,Huiyong Li,Dafeng Hu,Hao Jiang,Xuemin Geng,Jiangwei Lu,Xudong Zhang,Peng Yang,Yanfen Wan
Fe 3 O 4 nanoparticles (NPs) with a face-centered cubic (fcc) structure and two different morphologies (nanospheres and nanoprisms) were synthesized by a facile one-step method. The synthesized Fe 3 O 4 nanospheres and nanoprisms were monocrystalline and separable in a magnetic field. In different volume ratios of oleylamine (OAm) to dibenzyl ether, the sizes of the prepared Fe 3 O 4 NPs ranged from 5 to 21 nm. The OAm amount in the synthesis can significantly control the morphology of Fe 3 O 4 NPs. As the OAm content increased from 10 ml to 30 ml, the faceted nanoprisms shrank while the nanospheres enlarged. At an OAm content of 25 ml, the nanoprisms diminished while more hexagonal and sphere-like particles appeared, implying a critical point of morphology transition from triangle to hexagon. The magnetic properties also depended on the NP morphology and size. The prepared Fe 3 O 4 NPs are promising candidates in medical applications such as magnetic resonance imaging, targeted drug delivery, blood purification, and tumor hyperthermia.
研究领域:
材料科学
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医学工程
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纳米技术
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DOI
高影响因子
CRYSTENGCOMM
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2018
·Vol. 20
·期 32
·4651-4665
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IF 3.304
Rui Zhang,Qi Wang,Jun Zhang,Lili Yin,Yao Li,Shu Yin,Wenbin Cao
Shape-controllable SnO microstructures were successfully synthesized via a facile inorganic alkali-assisted hydrothermal method. The morphologies of the prepared samples could be simply modulated from plate-like blocks to hierarchical architectures assembled using nanosheets with tuned thicknesses, including flowers, bird nests and microspheres, through varying the alkali used in the synthesis process. Based on the experimental results, the origins and detailed formation mechanisms of the plate-like and hierarchical SnO architectures were comprehensively proposed. It was found that the formation of SnO was governed by dissolution–recrystallization and an oriented attachment process; the different dissociation rates of various alkalis played an important role in the final SnO morphology. The thicknesses of the assembling nanosheets greatly decreased with an increase in the dissociation rates of the alkalis. Furthermore, it was proved experimentally that all the hierarchical SnO structures exhibited better photocatalytic activities than those of the plate-like structures in the photodegradation of MB under fluorescent and UV light irradiation. The microspheres, with decreased size and assembling nanosheets of decreased thickness, showed the highest activity for MB dye degradation owing to an increased specific surface area and the reduced recombination of photogenerated electron–hole pairs. The mechanism for the photocatalytic degradation of MB over SnO was discussed in detail.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
RSC Advances
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2015
·Vol. 5
·期 48
·38373-38381
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IF 3.84
Xin Xiao,Ruiping Hu,Shunheng Tu,Chunxia Zheng,Huan Zhong,Xiaoxi Zuo,Junmin Nan
β-Bi2O3 micro/nanostructures with tunable morphologies were synthesized via a one-pot solvothermal–calcining route, and their photocatalytic activity toward degrading methylparaben (MeP, a widely used preservative with estrogenic activity) was evaluated under visible-light (λ ≥ 420 nm) irradiation. The formation process of β-Bi2O3 catalysts can be described as reduction of Bi3+ through a solvothermal reaction, followed by oxidization of metal Bi via calcination in air. During this process, the organic reductants (single or a mixture of ethylene glycol, D-fructose, and ascorbic acid) play important roles in determining the final morphologies and structures of the materials. Photocatalytic tests reveal that MeP can be effectively degraded and mineralized by using synthetic β-Bi2O3 catalysts, and the reaction rate constant of an optimum sample is more than 25 and 160 times faster than a commercial Bi2O3 and synthetic N-TiO2, respectively. The superior photocatalytic activity of the optimum product is ascribed to its pure beta phase with a narrower band gap, good absorption of visible light, more efficient separation of electrons and holes, relatively higher BET specific surface area, and three-dimensional architectures, which favor more surface active sites and easier mass and photoinduced charge transportations. In addition, the main reactive oxygen species and possible degradation intermediates were detected, and the results suggest that photogenerated holes and superoxide radicals are the predominant species in the photochemical oxidation process.
研究领域:
材料科学
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环境科学
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化学工程
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DOI
高影响因子
ChemCatChem
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2014
·Vol. 6
·期 12
·3419-3425
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IF 5.044
Yongliang Liao,Shenmin Zhu,Jun Ma,Zhihua Sun,Chao Yin,Chengling Zhu,Xianghong Lou,Di Zhang
Graphical Shaping graphitic nitrides: Synthesis of graphitic carbon nitride (g-C 3 N 4 ) and tailoring of its morphology was performed through adjustment of the molar ratio of melamine to urea, their self-assembly by hydrogen bonding and ionic interactions, and calcination. We report a novel method for the preparation of graphitic carbon nitride (g-C 3 N 4 ) with various morphologies through self-assembly and calcination, which starts from the raw materials melamine, urea, and cyanuric acid. The hollow to wormlike morphologies of g-C 3 N 4 could be readily tailored by adjusting the molar ratio of melamine to urea; with increase in the molar ratio from 3:1 to 1:3, a morphology transformation was observed. The morphologies were tailored by self-assembly of the aggregates by hydrogen bonding and ionic interactions. Correspondingly, an increased BET surface area from 49.6 to 97.4 m 2 g −1 was observed. If used as a photocatalyst in degrading rhodamine B (RhB) under visible-light irradiation, these g-C 3 N 4 samples demonstrated 7 to 13 times higher performance than conventional bulk g-C 3 N 4 . The high performance was attributed to the unique morphology that provided not only high specific surface area but low recombination losses of photogenerated charges.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2017
·
IF 9.446
Danjun Mao,Shanshan Ding,Lingjun Meng,Yuxuan Dai,Cheng Sun,Shaogui Yang,Huan He
The novel Bi-rich Bi 4 O 5 Br 2 with tunable morphologies of two-dimentional (2D) nanosheets (NSs), three-dimentional (3D) monodisperse layered microspheres (LMs) and hollow spheres (HSs) have been successfully synthesized via an ionic liquid-in-water (IL/W) microemulsion method. Surfactant TX-100 served as the stabilizer of the IL/W microemulsion, and its concentration significantly influenced the morphology and size of the resulting Bi 4 O 5 Br 2 crystal. Possible formation mechanisms have also been discussed. UV–vis diffuse-reflectance spectra and Density function theory (DFT) calculations indicated that Bi 4 O 5 Br 2 possessed stronger visible light adsorption and more negative conduction band minimum (CBM), which is beneficial to effectively activate molecular oxygen to produce O 2 − . The photocatalytic activity of Bi-rich Bi 4 O 5 Br 2 with varied shapes was investigated and compared with BiOBr for the removal of fungicide o-phenylphenol (OPP) and antibacterial agent norfloxacin (NOR) and tetracycline hydrochloride (TC) under visible light irradiation. The as-prepared Bi 4 O 5 Br 2 HSs and LMs possess higher photocatalytic efficiency than Bi 4 O 5 Br 2 and BiOBr NSs, which is attributed to the hollow/layered spherical structures and Bi-rich strategies. The O 2 − and h + are identified to be the major photoactive species during the photo-degradation process by scavenger experiments and EPR methods. This study is expected to provide a stepping stone to purposively design and explore other novel hollow structures with controllable morphology and enhanced photocatalytic activity.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
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2022
·Vol. 57
·期 28
·13541-13559
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IF 4.682
He Geping,Wang Di,HuangFu Huijun,Zhang Cunshe,Zhang Ben,Mi Yuanmei,Zheng Donghao
ZnWO 4 nanomaterials are gaining attention as a kind of multifunctional material in the field of electrochemical energy storage and photocatalysis. However, the controllable adjustment of their nanomorphology and bandgap width limit their wide application. So the nanostructured bifunctional Zn 1− x Ce x WO 4 ( x = 0.020, 0.022, 0.030) with tunable nanomorphology and bandgap width were prepared by a simple one-step hydrothermal method in this work. On the one hand, the microscopic morphology of the Zn 1− x Ce x WO 4 was changed from clusters to nanosheets with the addition of Ce 4+ . On the other hand, the doping of Ce 4+ generated oxygen vacancies and formed defect states in the ZnWO 4 semiconductor, reducing the energy bandgap width. Zn 1− x Ce x WO 4 ( x = 0.022) with the optimal doping ratio (nCe/(nCe + nZn) = 0.022) obtained a specific capacitance of 267.091 F g −1 at a current density of 1 A g −1 and an electrolyte of 6 M KOH, which is 3.7 times as great as the specific capacitance of ZnWO 4 (70.545 F g −1 ). In addition, the catalytic efficiency of Zn 1− x Ce x WO 4 ( x = 0.022) for Rhodamine B (RhB) reached 99.541% in 4.5 h. The doping of Ce 4+ can achieve the dual modulation of the morphology and bandgap width of ZnWO 4 , thus enhancing the electrochemical performance and photocatalytic degradation performance of ZnWO 4 . Graphical abstract
研究领域:
材料科学
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环境科学
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电化学
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2022
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IF 6.371
Jingyun Wang,Wei Li,Xiaofang Chen,Aisheng Huang
Transition metal phosphides are considered as promising alternatives to noble-metal based electrocatalysts for water splitting due to their bifunctional catalytic activity. The modulation of morphology and electronic structure is an efficient strategy to improve the mass transport and electronic conductivity of metal phosphides, but still faces a great challenge to achieve this conjoint regulation. Herein, a facile Zn-doped strategy was developed to synthesize cobalt phosphide (CoP) catalyst with thickness-controlled porous nanosheet structure. At the current density of 10 mA cm −2 , the optimized Zn 0.1 -CoP catalyst delivers an overpotentials of 290 mV and 98 mV for OER and HER , respectively. The cell voltage for the overall water splitting is 1.57 V to reach the current density of 10 mA cm −2 , outperforming the counterparts of noble metal-based Pt/C and IrO 2 catalysts. The density functional theory (DFT) calculations reveal that Zn doping can effectively improve the conductivity and regulate the electronic structure of CoP, thus resulting in fast charge transfer transport and reduced energy barrier of the rate-determining step. This work provides a favorable strategy for the rational design of bifunctional catalysts with high-performance for overall water splitting.
研究领域:
材料科学
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电催化
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产品关联
DOI
高影响因子
Nanoscience and Nanotechnology Letters
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2019
·Vol. 11
·期 6
·804-812
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IF 0
Chen Ling,Liu Yumeng,Matras-Postolek Katarzyna,Yang Ping
Graphitic carbon nitride (g-C3N4) nano-materials with different morphologies were prepared in this study by two-steps through controlling the mercapto group-induced assembly. Mercaptopropyl trimethoxysilane (MPS)-decorated SiO2 nanospheres were employed
as hard templates to produce g-C3N4 in the first step. Different morphologies of g-C3N4, such as hollow spheres, nanotubes and quasi-belts, were created in the second step by controlling the concentration of etching agents, reaction time, and process.
During the etching process, the mercapto groups in MPS can induce the assembly of g-C3N4 and play a crucial role of tuning the morphologies of g-C3N4, which is the key point for morphology adjustment. To enhance photolysis activity, cobalt-, boron-,
and carbon-doped g-C3N4 were further prepared to tune the band gap and absorption in visible light. The morphologies of doped samples changed after doping. In addition, carbon self-doped g-C3N4 exhibited the best photo-redox activity due to increased
visible light absorbance, electrical conductivity, and narrow band gap.
研究领域:
材料科学
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环境科学
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化学
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DOI
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
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2016
·Vol. 99
·期 5
·1498-1503
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IF 2.787
Baoyan Chai,Luyuan Hao,Xiaojian Mao,Xin Xu,Xiaokai Li,Benxue Jiang,Long Zhang
Strontium fluorapatite particles with tunable morphologies and geometries were successfully synthesized via a precipitation system by adjusting the pH value and temperature. Several analysis techniques were used to investigate and characterize the particles. The surface energy was calculated using first-principle calculations based on density functional theory. Capsule-like nanosized primary grains with axial growth directions parallel to the c -axis were synthesized at higher pH values, resulting from the difference in surface energy for the different planes of the Sr 5 (PO 4 ) 3 F lattice. Bundle-like clusters were obtained at a pH value of ~7, which was attributed to a combination of the difference in surface energy and the phenomenon of heterogeneous nucleation occurring at low degrees of supersaturation. The study determined the approaches necessary to manufacture Sr 5 (PO 4 ) 3 F powders with specific characteristics for different applications.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2020
·Vol. 31
·期 19
·16332-16337
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IF 2.22
Yu Ping,Zhou Li,Jia Zhengfu,Wu Keyue,Cui Jingbiao
Te nanoplates, nanowires, and nanospheres were successfully synthesized by a hydrothermal method with glucose as a surfactant agent. By simply changing the reaction time, the morphology of Te nanostructures can be changed from nanoplates, to nanowires, and ultimately to nanospheres. The samples were studied by x-ray diffraction, scanning electron microscopy, transmission electron microscopy, x-ray photoemission spectroscopy, and photoluminescence measurements. It is found that the reaction time plays an important role in morphology formation and optical properties of Te nanostructures. A possible growth mechanism involving a self-assembly process and Wulff facets theorem is proposed to explain the formation of Te nanoplates, nanowires, and nanospheres. This study presents a simple way to control the morphology of Te nanostructures and their optical properties.
研究领域:
材料科学
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纳米技术
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产品关联
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2023
·
IF 4.5
Yinchen Dai,Jibiao Guan,Xiao Li,Baochun Guo,Lina Wang,Ming Zhang
The development and improvement of new transition metal-based catalysts to replace Pt/C electrodes in electrolytic water hydrogen evolution has attracted much attention. In this work, we used ammonium citrate as additive, mixed with cobalt nitrate, through hydrothermal and phosphating methods to get supported on carbon cloth catalyst with new morphology (referred to as E380-CoP/CC, E380 stands for ammonium citrate). Benefit from the dense and fine nanosheet structure, compared with cobalt phosphating alone, the catalyst E380-CoP/CC has a significant improvement in hydrogen evolution performance. In 1 M KOH, the overpotential is 57 mV at the current density of 10 mA cm −2 , and the Tafel slope is only 40 mV dec -1 , which is very close to the hydrogen evolution performance of Pt/C electrode. In addition, the catalyst has favorable stability and superior hydrogen evolution performance after undergoing CV 2000 cycles and 48 h i- t test. This work offers a reliable idea for realizing electrolytic water hydrogen evolution technology with high efficiency and energy saving.
研究领域:
材料科学
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电催化
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2023
·
IF 7.2
Yuwen Tian,Yuanzhi Hong,Bingqi Chen,Kun Zhang,Dunhua Hong,Xue Lin,Junyou Shi
Indium oxide (In 2 O 3 ) is a promising semiconductor used for various photocatalytic reactions, yet the green and template-free synthesizing the different micro/nanostructured In 2 O 3 with tunable morphology is still full of challenge. In this study, the three morphological In 2 O 3 with 3D micro-cubelike (In 2 O 3 -MC), 3D micro-ricelike (In 2 O 3 -MR), and 2D nano-platelike (In 2 O 3 -NP) were successfully fabricated through a facile hydrothermal strategy without any organic template additives. Owing to the enlarged specific surface area , promoted charge migration rate and suitable surface oxygen vacancies density, the unique 3D ricelike In 2 O 3 -MR exhibited the best photocatalytic H 2 generation activity from biomass glucose solution, which was 1.9-fold and 1.7-fold higher than that of In 2 O 3 -MC and In 2 O 3 -NP under the same experimental conditions. In addition, the optimum photoactivity of In 2 O 3 -MR was achieved under the alkaline environment with pH = 11 and 1.0 wt% Pt cocatalyst loading, which was better than the most of previously reported In 2 O 3 -based photocatalysts . Simultaneously, the possible photocatalytic mechanism for solar H 2 evolution from glucose solution was also discussed. Our work will bring about potential application in preparation of other photocatalysts with controlling morphology for renewable photocatalysis .
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）