SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Meifei Chen,Xiunan Cai,Qing Yang,Wenqin Lu,Zuqiang Huang,Tao Gan,Huayu Hu,Yanjuan Zhang
To improve the photocatalytic performance of g-C 3 N 4 (CN), mechanical activation (MA) treatment of precursor followed by calcination was developed to construct a N−Mo−O bond bridged MoO 2 /Mo-doped CN (MA-MoO 2 /Mo-CN) Schottky heterojunction composite, which was used as a visible light-driven photocatalyst for degrading tetracycline (TC). The as-prepared MA-MoO 2 /Mo-CN with strong interfacial interaction showed excellent photocatalytic performance and structural stability, with 92.3% of TC degradation efficiency within 90 min and maintaining over 90% of degradation efficiency after five consecutive cycles. The enhanced photocatalytic performance can be ascribed to that MA treatment induced the improvement of surface area and the formation of N vacancies and N−Mo−O bonds, which served as a bridge to connect Mo-CN and MoO 2 for constructing a Schottky barrier. These provided more reactive sites and effectively enhanced migration efficiency of interface electrons, separation efficiency of photogenerated carriers, and light absorption capacity. In addition, the mechanism of photocatalytic degradation of TC and its possible degradation pathway were investigated. This research provides an environmentally friendly and feasible method for producing highly active precious metal-free photocatalysts with excellent migration and separation efficiency of photoexcited charge carriers.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2023
·
IF 5.4
Zhenjun Qing,Huapeng Zou,Xin Zhou,Haiyan Li,Yingxiang Li
This study presents the synthesis of LiYMo 2 O 8 ceramic through a solid-state reaction. XRD analysis reveals a tetragonal structure (I41/a space group) for the LiYMo 2 O 8 phase. The sample sintered at 800 °C achieved a maximum relative density of 95.8 % and exhibited excellent microwave properties: ε r = 15.7, Q × f = 24380 GHz, and τ f = 147.6 ppm/ °C. The results demonstrate a positive correlation between the relative density and both ε r and Q × f , while Q × f and τ f are found to be associated with packing fraction and Mo-O bond valence, respectively. The microwave dielectric properties are predominantly influenced by the Mo-O bond, as supported by the P-V-L theory and Raman spectroscopy analysis. Furthermore, the study reveals a correlation between ε r and the ionicity of chemical bonds, a significant impact of lattice energy on Q × f , and a relationship between τ f and bond energy and thermal expansion coefficient.
研究领域:
材料科学
·
固态化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Chengzhi Xu,Hongyu Yang,Linzhuang Xing,Yuan Wang,Guorui Zhao,Li Chen,Zhimin Li
The Al 2 Mo 3 O 12 ceramic with monoclinic type is prepared at the sintering temperature as low as 750 °C, which exhibits excellent microwave dielectric properties of ε r = 4.99, Q × f = 49,579 GHz ( f = 14.8 GHz), and τ f = −26 ppm/°C. The relationship between structure and characteristics is analyzed through the P–V–L chemical bond theory in depth, and the dielectric properties are investigated in combination with far-infrared spectroscopy. Results show that it is Mo–O bond that is responsible mainly for bond ionicity and dielectric polarizability, and structural stability as well. Based on the far-infrared reflectivity spectra and complicated dielectric function analysis, the calculated and measured results are in relative agreement using the classical damped oscillation mode, indicating that the mode at 80.23 cm −1 is dominant for the contribution to dielectric properties. This study gives an insight into the structural characteristic and provides a guide to further improve the microwave dielectric performance of Al 2 Mo 3 O 12 ceramic.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Zhiliang Jin,Teng Li,Kai Wang,Xin Guo
Simple high-temperature calcination and hydrothermal methods were followed to synthesize CeO 2 and Mo-S, respectively. The efficient photocatalytic hydrogen evolution activity exhibited by the composite catalysts can be attributed to the edge active sites in Mo-S. The Mo-O bonds formed between CeO 2 and Mo-S could further accelerate the processes of separation and migration of electrons between the catalyst interfaces. The hybrid catalyst 10%-CeO 2 /Mo-S exhibiting the best hydrogen generation ability (4.3 mmol h −1 g −1 ) was obtained by optimizing the content of CeO 2 in CeO 2 /Mo-S. Analysis of the PL spectral profile and photocurrent response recorded for the system revealed that 10%-COMS exhibited excellent photogenerated carrier separation ability. Analysis of the LSV and EIS curves revealed that 10%-COMS exhibited the optimal hydrogen production potential. The charge migration resistance provided by the systems was lower than the charge migration resistance provided by CeO 2 and Mo-S. The synergism between the S-scheme heterojunctions and the Mo-O bonds helped accelerate the separation and migration of photo-induced carriers at the catalyst interfaces. The introduction of covalent bonds in the S-scheme heterojunctions and the results presented herein can potentially help develop a new method to realize photocatalytic hydrogen evolution.
研究领域:
材料科学
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能源科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2023
·Vol. 107
·期 1
·223-233
·
IF 3.9
Zhenjun Qing,Huapeng Zou,Xin Zhou,Haiyan Li,An Liu,Shumin Duan,Yingxiang Li,Sen Peng
Li 2 Co 2 Mo 3 O 12 (LCMO) ceramics were synthesized using the solid-state reaction method. X-ray diffraction analysis results indicated that the sole crystalline phase present in the ceramics was LCMO, which belongs to the orthorhombic structure of the Pnma space group. The sample, which was sintered at 850°C, demonstrated outstanding microwave dielectric properties, with an ε r value of 8.95, a Q × f value of 43 200 GHz, and a τ f value of –71.3 ppm/°C. It was found that while the main factor influencing ε r was ionic polarizability, sintering density had a lesser effect on it. Furthermore, Q × f was primarily affected by relative density, and there was no significant relationship between packing fraction and this property. The higher the degree of distortion of the [Li/CoO 6 ] octahedron is, the poorer the τ f value of LCMO ceramics. Additionally, the microwave dielectric properties of LCMO ceramics were intrinsically linked to ionicity, lattice energy, bond energy, and thermal expansion coefficient of chemical bonds, with Mo–O bonds being the primary factor affecting these properties, as supported by analysis using chemical bonding theories. Mo–O bond vibration dominated the Raman spectra. Good chemical compatibility between silver and LCMO ceramics was demonstrated through our co-firing experiment.
研究领域:
材料科学
·
陶瓷
·
微波介质
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固态化学
·
拉曼光谱
✓ 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）