Journal of Energy Chemistry
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2016
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IF 2.322
Xin Liu,Junzhe Jiang,Yushuai Jia,Ailing Jin,Xiangshu Chen,Fei Zhang,Hongxian Han
Pure phase, regular shape and well crystallized nanorods of p-type semiconductor CaFe 2 O 4 have been fabricated for the first time by a facile molten salt assisted method, as confirmed by XRD , TEM, SEM and HRTEM. UV−vis diffuse reflectance spectra and Mott–Schottky plots show that the band structure of the CaFe 2 O 4 nanorods is narrower than that of the CaFe 2 O 4 nanoparticles synthesized by conventional method. The enhancement of the visible-light absorption is due to narrowness of the band gap in CaFe 2 O 4 nanorods. The appropriate ratio between the molten salt and the CaFe 2 O 4 precursors plays an important role in inhibiting the growth of the crystals along the (201) plane to give the desired nanorod morphology. This work not only demonstrates that highly pure p-type CaFe 2 O 4 semiconductor with tunable band structure and morphology could be obtained using the molten salt strategy, but also affirms that the bandgap of a semiconductor may be tunable by monitoring the growth of a particular crystal plane. Furthermore, the facile eutectic molten salt method developed in this work may be further extended to fabricate some other semiconductor nanomaterials with a diversity of morphologies.
研究领域:
材料科学
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半导体物理
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产品关联
DOI
高影响因子
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
·
2025
·
IF 7.8
Wencheng Hou,Wentao Guo,Xiangjun Liu,Zhuoyang Li,Hongxia Li
Desulfurized gypsum, a byproduct of industrial processes, can be efficiently recycled through solid-phase reaction to synthesize CaFe 2 O 4 . This study investigates the reaction mechanism of CaFe 2 O 4 formation from CaSO 4 , Fe 2 O 3 , and semi-coke powder using thermodynamic modeling with Factsage 8.3 software. The phase composition and microstructure of the resulting products under varying semi-coke contents and sintering temperatures were characterized using X-ray diffraction (XRD) and scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM-EDS). Total Fe and S contents were quantified using inductively coupled plasma optical emission spectroscopy (ICP-OES) and a C/S Analyzer. The results indicate that increasing the semi-coke content from 11.11 wt% to 20.00 wt% leads to an initial rise and subsequent decline in CaFe 2 O 4 yield, while S content exhibits an opposite trend. Similarly, elevating the sintering temperature from 1050°C to 1150°C results in increased CaFe 2 O 4 formation up to 1125°C, beyond which a decrease is observed, alongside a continuous reduction in S content. Optimal synthesis conditions were identified at 15.79 wt% semi-coke and 1125°C, achieving a desulfurization rate of 95.40 % and confirming effective formation of CaFe 2 O 4 . Compared to conventional reducing agents such as coke and C powders, the use of semi-coke enabled a reduction in the required sintering temperature from 1150°C to 1125°C. These results provide a valuable reference for the low-temperature, high-efficiency recycling of desulfurized gypsum into functional ferrite materials.
研究领域:
材料科学
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环境工程
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产品关联
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2017
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IF 2.813
Xin Liu,Yuhong Zhang,Yushuai Jia,Junzhe Jiang,Yabin Wang,Xiangshu Chen,Tian Gui
We report the fabrication and photocatalytic property of a composite of C/CaFe 2 O 4 nanorods (NRs) in an effort to reveal the influence of carbon modification. It is demonstrated that the photocatalytic degradation activity is dependent on the mass ratio of C to CaFe 2 O 4 . The optimal carbon content is determined to be 58 wt% to yield a methylene blue (MB) degradation rate of 0.0058 min −1 , which is 4.8 times higher than that of the pristine CaFe 2 O 4 NRs. The decoration of carbon on the surface of CaFe 2 O 4 NRs improves its adsorption capacity of the MB dye, which is specifically adsorbed on the surface as a monolayer according to the adsorption isotherm analysis. The trapping experiments of the reactive species indicate that superoxide radicals ( • O 2 − ) are the main active species responsible for the removal of MB under visible-light irradiation. Overall, the unique feature of carbon coating enables the efficient separation and transfer of photogenerated electrons and holes, strengthens the adsorption capacity of MB, and improves the light harvesting capability, hence enhancing the overall photocatalytic degradation of MB.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
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2020
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IF 6.155
Sheng Guo,Zhixiong Yang,Huali Zhang,Wei Yang,Jun Li,Kun Zhou
A simple sol-gel approach is proposed herein to fabricate CaFe 2 O 4 for the degradation of various organic pollutants (rhodamine B (RhB), tetracycline hydrochloride, humic acid, and methylene orange) under LED light irradiation mediated by peroxymonosulfate (PMS). The results indicate that the calcination temperature can significantly influence the performance of CaFe 2 O 4 for PMS activation, and the CaFe 2 O 4 sample obtained at 800 °C (CaFe 2 O 4 -800) exhibits the best efficiency in degrading RhB, which is much higher than that of Fe 2 O 3 -800. This can be attributed to the efficient separation of photogenerated electrons (e − ) and holes (h + ) by PMS, which is validated by transient photocurrent response and photoluminescence measurements. Results from density functional theory calculations indicate that the valence band of CaFe 2 O 4 -800 exhibits a high concentration of carriers and weak localization of electrons, which are favorable for PMS activation. Radical scavenging results confirm that h + and O 2 • − are the dominant reactive species. Moreover, CaFe 2 O 4 -800 not only demonstrated a stable performance during eight cycling runs with negligible iron leaching but also exhibited excellent degradation efficiency under natural water and sunlight. Finally, the mechanism and pathway of RhB degradation by the CaFe 2 O 4 -800/PMS/LED system are also proposed. This work presents the enormous prospect of CaFe 2 O 4 as an environmentally benign photocatalyst for PMS activation.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
KOREAN JOURNAL OF CHEMICAL ENGINEERING
·
2023
·Vol. 40
·期 5
·1122-1132
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IF 2.7
Hua Weijie,Kang Yong
A coupling method of water surface plasma (WSP) with β -Bi 2 O 3 /CaFe 2 O 4 composite was applied to promote the elimination of aqueous Orange G (OG). The morphology, structures, crystal form and chemical bonding state of the prepared β -Bi 2 O 3 /CaFe 2 O 4 composite were characterized via SEM, TEM, EDS-mapping, XRD, FT-IR and XPS. The results showed that the addition of composites significantly enhanced the degradation and kinetic constant of OG. The degradation efficiency of the combined system containing 8.0 wt% β -Bi 2 O 3 /CaFe 2 O 4 composite was 28.9% higher compared to the sole WSP for OG degradation. The synergistic factor (2.387) demonstrated that the combined system was able to establish a synergistic effect. The effect including peak voltage, air flow rate, initial conductivity and initial concentration of solution on OG removal was inspected. The active species trapping experiments demonstrated ·OH, h + , ·O
− 2
and high-energy electrons devoted to OG removal in the combined system. O 3 and H 2 O 2 were also involved in the OG removal in the combined system. Three-dimensional fluorescence spectroscopy and liquid chromatography-mass spectrometry were tested to investigate the mechanism of OG degradation. Finally, the combined system in the present study was compared with other competitive technologies for the degradation of OG in the literature.
研究领域:
环境科学
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化学工程
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材料科学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
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IF 7.312
Weijie Hua,Yong Kang
Due to the increasingly severe water contamination of antibiotics, high-efficient and green removal of antibiotics from aqueous solution is of great significance to environmental remediation and human health. The combined degradation of tetracycline hydrochloride (TCH) in water by pulsed discharge plasma on water surface (WSPDP) coupled with CaFe 2 O 4 /Bi 2 O 3 composite was investigated. The basic properties of the prepared CaFe 2 O 4 /Bi 2 O 3 composite were analyzed by XRD , SEM, TEM, PL and XPS, which indicated that the CaFe 2 O 4 /Bi 2 O 3 sample was synthesized successfully. Degradation performance revealed that there existed a synergistic effect in the WSPDP + CaFe 2 O 4 /Bi 2 O 3 system, and WSPDP could induce catalysis of CaFe 2 O 4 /Bi 2 O 3 composite. After adding 0.4 g/L 7 wt% CaFe 2 O 4 /Bi 2 O 3 sample to the WSPDP system, the degradation efficiency of TCH improved from 82.9% to 93.8%, and the kinetic constant enhanced from 0.0616 min −1 to 0.0953 min −1 after 30 min of discharge treatment. Furthermore, the effects of pulse peak voltage, pulse frequency, initial pH of solution and air flow rate on TCH degradation were evaluated. The highest TCH degradation efficiency of 97.8% could be obtained at the peak pulse voltage of 24.6 kV, pulse frequency of 50 Hz, initial pH of 3 and air flow rate of 2 L/min within 30 min. OH, h + and O 2 − were the main reactive radicals for TCH degradation in the WSPDP + CaFe 2 O 4 /Bi 2 O 3 system·H 2 O 2 and O 3 were also involved in TCH degradation of the synergistic system, and the addition of CaFe 2 O 4 /Bi 2 O 3 could significantly improve the utilization of H 2 O 2 and O 3 in the solution. The intermediates of TCH degradation were identified by liquid chromatography-mass spectrometry (LC-MS). Finally, the possible degradation pathways and synergistic degradation mechanism of TCH in the WSPDP + CaFe 2 O 4 /Bi 2 O 3 system were proposed.
研究领域:
环境科学
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水处理
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高级氧化过程
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催化
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污染物降解
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Menghang Qi,Liangsheng Tian,Qiuying Wang,Ruoxiu Xiao,Nan Hu,Lin Shi,Theeranun Siritanon,Peng Jiang
The CaFe 2- x In x O 4 (0 ≤ x ≤ 1) pigment with red shade was successfully synthesized through solid state reactions. The crystal structure, color development mechanism, morphology and its application in the glaze were studied. XPS analysis confirmed Fe resides in +3 oxidation state. Combined with UV-Vis-NIR analysis, it is determined that the formation of red shade of the pigment is due to the 6 A 1 (S) → 4 T 2 (D), 6 A 1 (S) → 4 A 1 , 4 E(G) and 6 A 1 (S) → 4 T 2 (G) transitions of Fe 3+ in the visible light region. The pigment was applied to the lead-free low temperature glaze to evaluate its potential in preparing new glaze color. The as-synthesized glaze showed orange-red shade. With increased In 3+ doping concentration, the glaze demonstrates a stronger red tone. The glaze also shows high NIR solar reflectance. Inferred from SEM-EDS, the pigment particles are evenly scattered in the glaze. Therefore, CaFe 2- x In x O 4 (0 ≤ x ≤ 1) red pigment is a qualified candidate for red shade glaze preparation.
研究领域:
材料科学
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陶瓷学
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无机化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）