CHEMICAL PHYSICS LETTERS
·
2021
·
IF 2.328
Jie Zhang,Tianyu Liu,Liangjie Fu,Gonglan Ye
As an emerging material, exfoliated molybdenum disulfide (MoS 2 ) has an excellent performance in catalysis, electronics and adsorption. However, the application performance of exfoliated MoS 2 is limited by the strong adhesion between MoS 2 layers and the low colloidal stability of MoS 2 in water. In this study, for the first time, nanosized ultrathin MoS 2 was successfully synthesized on exfoliated montmorillonite (MMT) by CVD method. Two reaction mechanisms were found when using flow gas with or without H 2 . The introduction of H 2 promotes the growth of MoS 2 crystals and reduces nucleation density. The MoS 2 /MMT showed excellent performance in dye degradation.
研究领域:
材料科学
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催化化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2022
·
IF 6.371
Li Lv,Yinglin Wang,Pengfei Cheng,Yue Zhang,Yaoqiong Zhang,Zhaohui Lei,Luping Xu,Zhi Weng
In this study, a one-step chemical vapor deposition (CVD) method was used, utilizing template NaCl and dextrin as the porogen and structural support. The synthesized spinel MFe 2 O 4 (M = Zn, Ni, Cu, Co and Mn) microspheres with multiple cavities structure were applied to the acetone gas sensor detection. Through the characterization of the sensitive materials, the average pore diameter of the microspheres was about 60 nm. Compare with other metal cations , when M = Zn or Ni, the MFe 2 O 4 samples revealed the super gas sensitivity at working temperatures of 250 °C and 175 °C, and the response values to 100 ppm acetone were 25 and 24.3, respectively. In addition, they also exhibited excellent selectivity and long-term stability to acetone. The excellent gas sensitivity of ZnFe 2 O 4 and NiFe 2 O 4 could be attributed to the replacement of Fe with Zn and Ni ions to obtain a higher Fe 3+ /Fe 2+ atomic ratio, thereby increasing the content of adsorbed oxygen. In summary, the gas sensing performance of spinel MFe 2 O 4 oxide had been systematically studied by replacing Fe with other transition metals. The iron-containing spinel oxides are expected to be promising sensing material for gas sensors due to their rich elements and excellent activity.
研究领域:
材料科学
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传感器技术
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DOI
高影响因子
ChemistrySelect
·
2024
·Vol. 9
·期 43
·e202403902
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IF 1.9
Yi Chang,Jinsong Yang,Bin Qi,Xinxin Yuan,Hailu Huang,Lele Xu,Hualian Zhang,Yangyang Huai
Graphical In a typical FCCVD process, the purity of the initial product grown by the standard process was more than 90 wt%, with a yield of 0.5 g/h. The average G/D ratio of the initial product was 178, and it had a distinct RBM peak. HRTEM confirmed that the synthesized SWCNTs had high purity and crystallinity. Carbon nanotubes (CNTs) were synthesized by floating catalyst chemical vapor deposition (FCCVD) reactions. The complicated processing parameters that included a precursor solution composition, reaction temperature, flow rate of the carrier gas, weak oxidants, and injection rate of the precursor solution were controlled to synthesize single-walled carbon nanotubes (SWCNTs) during the reaction process. The effects of the processing parameters were analyzed with respect to the formation of SWCNTs, yield, and the crystallinity in the CNTs structure. The SWCNTs were characterized by the Raman spectroscopy, scanning electron microscope, high-resolution transmission electron microscopy, and thermogravimetric analysis. A high reaction temperature, high H 2 flow rate, low injection rate of solution precursor, and low concentrations of iron catalysts in the reaction were important factors to improve the crystalline quality of the SWCNTs. The purity of the initial product grown by the standard process was more than 90 wt %, with a yield of 0.5 g/h. The average G/D ratio of the initial product was 178, and it had a distinct RBM peak. HRTEM confirmed that the synthesized SWCNTs had high purity and crystallinity. The SWCNTs could be tunable to meet a particular application by varying the reaction conditions.
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
NEW JOURNAL OF CHEMISTRY
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2023
·Vol. 47
·期 23
·11051-11062
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IF 3.3
Chengzhi Hu,Changyan Zhou,Huiping Zhang,Ying Yan
Chemical vapor deposition (CVD) and impregnation (IM) methods were applied in the preparation of novel Fe/LTA (Linde Type A) zeolite membrane/paper-like sintered stainless steel fiber (Fe/LTA/PSSF) catalysts for acetone oxidation. The catalysts were characterized using various techniques, such as actual iron loading (AAS), surface morphology (SEM), phase composition and crystallite size (XRD), specific surface area (BET), valence state (XPS) and reducibility (H2-TPR), to investigate the effects of the calcination process, iron loading, preparation methods and supports on their catalytic activity. The calcined catalysts were more active than the non-calcined catalysts in the catalytic oxidation of acetone due to the different oxidation states of the deposited metal species. The catalysts prepared by CVD with an Fe loading of 2.29% exhibited similar activity to the IM-prepared catalysts with Fe loadings of 4.42% and 9.69%, which may be attributed to the superior dispersion of the active Fe2O3 phases, the smaller size of metal oxide and the increased ability for oxygen storage. Among the IM-prepared catalysts, Fe/LTA/PSSF-IM-2 with an Fe loading of 4.42% exhibited the lowest T90 of 230 °C. Additionally, the catalysts coated on LTA/PSSF showed higher activity and contact efficiency (T90 of 249 °C) compared to those on granular zeolite (T90 of 318 °C).
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2017
·
IF 3.615
Yong Zhang,Huiping Zhang,Ying Yan
A heterogeneous catalyst (Cu/ZSM-5) was prepared by a metal-organic chemical vapor deposition (MOCVD) method under nitrogen atmosphere using Cu(acac) 2 as the copper precursor, and further characterized by XRD , AAS , SEM, BET, H 2 -TPR and XPS as well as catalytic activity performance for the oxidation of toluene. N 2 adsorption data revealed that the samples (CVD-4) prepared by MOCVD with calcination at 500 °C for 4 h possessed higher surface areas than that (CVD-BC) not calcined. The results of XPS demonstrated that CVD-4 exhibited higher redox property and more surface oxygen species compared with CVD-BC and IM (Cu/ZSM-5 catalyst prepared by impregnation). In particular, the CVD-4 catalysts prepared by MOCVD with calcinations showed the highest catalytic activity for toluene oxidation with 90% conversion of toluene at 293 °C with the feed concentration of 1000 ppm and GHSV of 15,000 h −1 , which was lower than IM (310 °C). The results of a reaction durability test revealed that the Cu/ZSM-5 catalysts prepared by MOCVD possessed excellent durability for toluene oxidation for 63 h, while the conversion of toluene fell down from 90% to 60% after 48 h over IM catalyst.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Royal Society Open Science
·
2018
·Vol. 5
·期 3
·
IF 2.504
Yi Yang,Huiping Zhang,Ying Yan
Fe2O3-ZSM-5 catalysts (0.6 wt% Fe load) prepared by metal-organic chemical vapour deposition (MOCVD) method were evaluated in the catalytic wet peroxide oxidation (CWPO) of m-cresol in a batch reactor. The catalysts have a good iron dispersion and small iron crystalline size, and exhibit high stability during reaction. In addition, the kinetics of the reaction were studied and the initial oxidation rate equation was given. Catalysts were first characterized by N2 adsorption–desorption isotherms, scanning electronic microscopy, energy-dispersive spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy. Results show that extra-framework Fe3+ species (presenting in the form of Fe2O3) are successfully loaded on ZSM-5 supports by MOCVD method. Performances of catalysts were tested and effects of different temperature, stirring rate, catalyst amount on hydrogen peroxide, m-cresol, total organic carbon (TOC) conversion and Fe leaching concentration were studied. Results reveal that catalytic activity increased with higher temperature, faster stirring rate and larger catalyst amount. In all circumstances, m-cresol conversion could reach 99% in 0.5–2.5 h, and the highest TOC removal (80.5%) is obtained after 3 h under conditions of 60°C, 400 r.p.m. and catalyst amount of 2.5 g l−1. The iron-leaching concentrations are less than 1.1 mg l−1 under all conditions. The initial oxidation rate equation −rA0=7.2×1011e−81300/RTCA is obtained for m-cresol degradation with Fe2O3-ZSM-5 catalysts.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Physica Status Solidi-Rapid Research Letters
·
2025
·
IF 2
Yuedong Wang,Jindong Bai,Zhiyi Liu,Xiao Guo,Fangyan Ang,Yuli Huang,Haipeng Xie,Han Huang
Transition metal oxide alloys, with tunable stoichiometric ratio, have garnered significant attention due to their unique electronic structure and diverse chemical properties. However, synthesis of micron-scale, single-crystalline transition metal oxide alloys remains a challenge due to their unique alloy structure and stringent synthesis conditions. Herein, a WSe 2 -assisted chemical vapor deposition method is reported for synthesizing W x Mo 1- x O 2 nanocrystals with various dimensions: nanorods, nanoplates, and nanodots. The microscopic (optical microscope, atomic force microscope, and scanning electron microscope) images reveal that the nanocrystals have well-defined non-layered polyhedral structures. The elemental composition is confirmed by Raman spectroscopy and energy dispersion spectroscopy. The change in phonon symmetry in nanorods and the blue shift of Raman peaks in nanocrystals demonstrate the significant role of the quantum confinement effect. The spatial distribution of the various dimensional nanocrystals provides insights into the possible growth mechanism and the key role of the WSe 2 in growth. The WSe 2 -assisted growth strategy for alloyed nanocrystals can expand the transition metal oxide alloy material library and offer a platform for exploring additional properties of transition metal oxide alloys.
研究领域:
材料科学
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纳米技术
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2020
·
IF 8.821
Jun Wang,Zhe Yang,Yang Li,Xiaobin Fan,Fengbao Zhang,Guoliang Zhang,Wenchao Peng,Shaobin Wang
Nitrogen doped porous carbon cage materials are successfully synthesized using a chemical vapor deposition (CVD) method. Several carbides are selected as templates and in situ removed by CCl 4 . NaNO 3 is then used to create porous structure , and a very large surface area (SSA) (1224 m 2 g -1 ) could be obtained. The obtained materials can activate peroxymonsulfate (PMS) for degradation of various organic pollutants effectively. By NaNO 3 , the nitrogen doping styles could be regulated and the percentage of graphitic N and C O group could be increased, which will alter the PMS-based oxidation from a radical pathway to a non-radical dominated process. This study provides a novel way for synthesis of carbocatalysts, which should have great potential in environmental remediation.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
InfoMat
·
2024
·Vol. 6
·期 12
·e12605
·
IF 22.7
Lei Luo,Jiuwei Gao,Lu Zheng,Lei Li,Weiwei Li,Manzhang Xu,Hanjun Jiang,Yue Li,Hao Wu,Hongjia Ji,Xuan Dong,Ruoqing Zhao,Zheng Liu,Xuewen Wang,Wei Huang
Two-dimensional transition metal dichalcogenides (2D TMDs) are promising as sensing materials for flexible electronics and wearable systems in artificial intelligence, tele-medicine, and internet of things (IoT). Currently, the study of 2D TMDs-based flexible strain sensors mainly focuses on improving the performance of sensitivity, response, detection resolution, cyclic stability, and so on. There are few reports on power consumption despite that it is of significant importance for wearable electronic systems. It is still challenging to effectively reduce the power consumption for prolonging the endurance of electronic systems. Herein, we propose a novel approach to realize ultra-low power consumption strain sensors by reducing the contact resistance between metal electrodes and 2D MoS 2 . A dendritic bilayer MoS 2 has been designed and synthesized by a modified CVD method. Large-area edge contact has been introduced in the dendritic MoS 2 , resulting in decreased the contact resistance significantly. The contact resistance can be down to 5.4 kΩ μm, which is two orders of magnitude lower than the conventional MoS 2 devices. We fabricate a flexible strain sensor, exhibiting superior sensitivity in detecting strains with high resolution (0.04%) and an ultra-low power consumption (33.0 pW). This study paves the way for future wearable and flexible sensing electronics with high sensitivity and ultra-low power consumption.
研究领域:
柔性电子学
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可穿戴传感器
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低功耗电子器件
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二维材料
·
纳米电子学
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物联网（IoT）
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人工智能硬件
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）