CERAMICS INTERNATIONAL
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2021
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IF 4.527
Jaures Syntyche Ndzila,Zhengmao Ye,Guojian Jing,Xiaolei Lu,Jiaming Wu,Jinpu Zhang,Shuxian Wang,Xin Cheng
Sr 4 Al 6 SO 16 is a kind of anhydrous sulfoaluminate that belongs to the sodalite family. In this paper, we demonstrate the effect of Fe 3+ ions addition on the hydration properties of two polymorphs of Sr 4 Al 6 SO 16 (namely pure orthorhombic and cubic). In solid-state reaction of orthorhombic Sr 4 Al 6 SO 16 , excessive 5 wt% SrSO 4 was used to compensate for the loss of sulfur. Results indicate that the hydration rate of cubic phase is faster than that of orthorhombic phase at early stage, but the heat release of the latter is more concentrated. The reason why the cubic phase has a faster earlier hydration kinetics may be due to the incorporation of Fe 3+ ions and the formation of SrFe 12 O 19 impurity phase, which introduce the defects in the structure, activate the crystal lattice , and increase the hydration activity. Both polymorphs react with water to form the reaction products first, and then no crystalline phase hydration product was precipitated after 72 h. In contrary to the XRD , amorphous AH 3 was clearly detected in TGA analysis in hydrated samples, probably due to poor crystallinity which cannot be detected by XRD. In addition, both polymorphs contain a lot of impurity phases, and their amounts are calculated using the Rietveld refinement method. Moreover, the addition of Fe 3+ ions is not only beneficial to adjust the cubic phase content, but also facilitates the relative particle growth. This work provides a useful platform for employing the Fe 3+ ions to regulate the hydration properties of Sr 4 Al 6 SO 16 .
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2016
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IF 3.014
Manjiao Deng,Mao Ye,Tao Li,Haitao Huang,Wen-Xiang Yuan,Heng Jiang,Peng Lin,Xierong Zeng,Shanming Ke
Ferroelectric perovskite KNbO 3 (KNO) nanosheets with cubic and orthorhombic phases were synthesized by a simple soft chemistry exfoliation at room temperature. KNO nanosheets could be simply obtained by peeling off the layered precursor K 2 NbO 3 F in water, while the phase structure of KNO could be controlled by using different precursors. The cubic KNO nanosheets were formed by exfoliating-restacking, while the orthorhombic nanosheets were produced by nucleation-ripening. The photocatalytic performance of these nanosheets has been exploited in degradation Rhodamine B dye. The cubic KNO nanosheets showed obviously better photocatalytic activity, which could be ascribed to its highest symmetry in the bulk structure and its unique electron structure. The high activity of the ferroelectric two dimensional nanosheets indicates a broad spectrum of applications in the photocatalyst fields.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2022
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IF 9.965
Longyan Wu,Xianhao Hua,Yu Li,Yuxin Zhang,Xiaogang Xue,Honggao Deng,Zhenggang Luo,Yuting Zhang
Due to high defect tolerance and multiphase allowance, AgInS 2 (AIS) quantum dots (QDs) provide chances for designing new type junctions via tailoring defects, size, or phase structure. These new type junctions potentially enhance photoelectric performance, such as photocatalytic H2 evolution (PHE). Here, ultra-small AIS QDs (∼1 nm) with well-defined exciton absorption were prepared aqueously via a reverse hot-injection procedure for the first time. A coalescence or fast aggregation-based growth was observed for coarsening at 95 or 135 ℃, respectively. XRD and TEM investigations revealed that the tetragonal-orthorhombic ( t -o) phase transition occurred via aggregation-based growth. The studies on phase transition kinetics resulted in fine-tailoring on AIS polymorphs, favoring t -o AIS junctions. UV–vis absorption spectra confirm the double absorption edge of the t -o heterophase junction with enhanced visible absorption. Steady and transient PL spectra suggest improvements in carriers’ separation/transfer in this t -o junction. As a result, the optimized t -o AIS shows superior photocatalytic H 2 evolution rates of 1022 μmol. g −1 . h −1 , 51.1 times that of t -AIS or 3.8 times that of o-AIS. This work is expected to provide new insight for designing ternary alloyed QDs with strongly coupled interfaces for effective H 2 generations.
研究领域:
材料科学
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纳米技术
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光催化
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS & DESIGN
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2017
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IF 4.364
Puhong Wen,Lili Ai,Taotao Liu,Dengwei Hu,Fangyi Yao
The regular orthorhombic Nb 2 O 5 (O-Nb 2 O 5 ) rectangle nanosheets dominantly exposed (010) facet are synthesized by a hydrothermal topological reaction with a precursor of K 4 Nb 6 O 17 ·4.5H 2 O (KNbO). The structure and morphology of the samples obtained at different temperatures and pH values of reacting solution are investigated. The results suggest that there are two topological reactions in this process. One is the acid-exchanging reaction transforming into H 4 Nb 6 O 17 ·3H 2 O (HNbO) nanosheets from KNbO rectangle nanosheets , and the other is dehydration reaction transforming into O-Nb 2 O 5 rectangle nanosheets from HNbO nanosheets. And the {010} facets of O-Nb 2 O 5 crystal are transformed from the {010} facets of HNbO crystal in the ingenious topological reaction. The photoelectric performance of the obtained O-Nb 2 O 5 nanosheets is evaluated by decomposing water to H 2 under 370 nm UV light illumination and measuring the accompanying photocurrent . The photocurrent density is 680 nA·cm − 2 generated by splitting water with O-Nb 2 O 5 nanosheets as photocatalyst , and it is 4.3 times of the contrast sample. The result indicates that the (010) facet of O-Nb 2 O 5 is one of the highest photocatalytic active surfaces and shows high photoelectric conversion efficiency. Thus, the O-Nb 2 O 5 nanosheets dominantly exposed (010) facet have potential applications in photocatalyst and photoelectric nanodevices .
研究领域:
材料科学
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光催化
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纳米材料
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无机化学
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能源材料
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
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2019
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IF 4.309
Caiju Chen,Mengling Liao,Beibei Shan,Ming Li
A fundamental understanding of the thermal stability of vacancy-doped cuprous telluride nanocrystals (Cu2–xTe NCs) will be conductive to their exploitation in plasmon-related applications. However, the thermally induced structural and Raman spectral changes of Cu2–xTe NCs have remained fairly unexplored so far. Here, temperature-induced structural transitions of Cu2–xTe nanowires (NWs) are studied by in situ Raman spectroscopy from −190 to 530 °C. Results reveal a dramatic temperature dependence of Raman signatures of Cu2–xTe NWs, serving as a potent indicator for their structures and structural transitions. The hexagonal weissite-to-orthorhombic phase transition takes place in the cooling process from 25 °C to −190 °C. An intermediate state of high degree of disorder with featureless Raman spectra is observed before its dissociation into the elemental Cu and the high-temperature phase above 480 °C. This work provides fundamental insights into the thermally induced structural stability of Cu2–xTe NWs and will further stimulate new exploration of their plasmon-related practical applications.
研究领域:
材料科学
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纳米技术
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光谱学
✓ 已验证
产品关联
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
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2020
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IF 6.984
Shusheng Pan,Ziyue Rao,Yujie Wu,Zhiyu Liu,Jun Ge,Shan Zhang
In this study, a temperature self-regulating solar reactor based on VO 2 thermochromic coating is demonstrated. The temperature of solar reactor can be stabilized at 68.8 °C, which is corresponded to the critical point of metal-to-insulator transition of VO 2 . By employing the solar reactor, the orthorhombic phase CsPbI 3 microwires have been synthesized through solution phase reaction route. Strong emission peaks at 490 nm and 470 nm have been observed in CsPbI 3 microwires under ultraviolet and soft X-ray excitation, respectively. The high performance photodetector based on CsPbI 3 microwire show a detectivity of 1.09 × 10 14 Jones, responsivity of 4.72 A/W, rapid rise and decay time of 0.96 and 0.93 s at 325 nm. Our results demonstrate that the temperature self-regulating solar reactor can be applied for energy-saving solution phase reactor for synthesizing high quality inorganic materials.
研究领域:
材料科学
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纳米光电子学
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无机功能材料
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能源材料
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半导体器件
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2023
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IF 9.9
Haofeng Chen,Chao Liang,Suhang Xun,Zhendong Yu,Cancan Wu,Minqiang He,Huaming Li,Wenshuai Zhu
Bimetallic oxide is a potential catalyst for oxidative desulfurization of fuel. Thus, an appropriate method is needed to improve its catalytic performance. Manufacturing defect is an effective means. In this contribution, an oxygen vacancies (OVs) regulation strategy for enhancing the catalytic activity of bimetallic oxide is proposed. Density functional theory (DFT) calculations show that the crystal phase has a huge influence on the generation energy of oxygen vacancies, so a series of V-Nb mixed oxide with different crystal phases are synthesized. Detailed characterizations show that the as-prepared tetragonal V-Nb mixed oxide ( T -VNbO x ) has lower OVs formation energy and larger OVs concentration (compared to orthorhombic V-Nb mixed oxides, O -VNbO x ). Owing to the activation of OVs, the catalytic activity of T -VNbO x was significantly enhanced to form ultra-deep oxidative desulfurization. In addition, T -VNbO x can be cycled eight times without significantly degrading the desulfurization performance.
研究领域:
催化
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材料科学
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环境化学
✓ 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）