APPLIED SURFACE SCIENCE
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2021
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IF 6.707
Ziying Hu,Jing Chen,Dongxu Yan,Yan Li,Hongpeng Jia,Can-Zhong Lu
Chlorinated volatile organic compounds (CVOCs) existing widely in the industries are harmful to the environment and human’s health. It is urgent to develop highly efficient catalysts for their combustion. Herein, a series of porous MnO x/ Co 3 O 4 nanocomposites are synthesized by the pyrolysis of Mn@Co-ZIF-67 precursors, in which the Mn ions are introduced by impregnation method. XRD, Raman, ICP-OES, BET, SEM, TEM, XPS, O 2 -TPD, and H 2 -TPR have been performed to investigate the as-prepared catalysts’ physicochemical properties. The optimal catalyst MnO x /Co 3 O 4 -4h exhibits 90% and 100% chlorobenzene (CB) conversion (1000 ppm, Air, WHSV = 60,000 mL/(g h)) at 334 °C and 350 °C, respectively. And the better catalytic performance over MnO x /Co 3 O 4 -4h compared with the pure Co 3 O 4 and other MnO x /Co 3 O 4 nanocomposites mainly ascribes to its porous structures, homogeneous dispersion, optimal Mn/Co molar ratio, more lattice defects, and higher surface O Latt /O Ads ratio. Meanwhile, MnO x /Co 3 O 4 -4h displays high stability and resistance to moisture. Main intermediates have been further investigated by in situ DRIFT, and the degradation mechanism has been proposed according to the analysis of intermediates.
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
Surfaces and Interfaces
·
2022
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IF 6.137
Xueqiang Liu,Diandi Li,Jiguang Li,Jianle Wang,Shujie Liang,Hong Deng
Heavy metal ion pollution (e.g., Hg, Pb, Cr, Cd) that has a great threat to human health is a global concern, because of their great toxicity (e.g., carcinogenicity and mutagenicity). Therefore, it is necessary to find an economical and efficient technology to remove metal. In recent years, modified biochar plays an important role in the removal of heavy metal. However, most of the biochar modification methods rely on high temperature and long time, which limits their application in practical engineering. In this study, we firstly synthesized HMBC (MnO X -OBC, peanut shells as raw materials) using H 2 O 2 -NaOH method, where the materials only need to be modified for 10 min at ambient temperature to obtain high adsorption performance. The maximum Pb(Ⅱ) and Cd(Ⅱ) adsorption capacities of HMBC were 164.59 mg g − 1 and 36.77 mg g − 1 , respectively, which were 7.2 times and 5.6 times that of the unmodified PBC (peanut shells derived biochar ) , and the main adsorption mechanisms were complexation, ion exchange, cation-π interaction and precipitation. The adsorption process of lead and cadmium by HMBC was more consistent with the Freundlich model and Pseudo-second-order adsorption kinetics . HMBC had high selectivity for lead and cadmium, and the adsorption performance of HMBC was basically not reduced after five cycles. The above experimental results show that the newly prepared HMBC has the potential to treat lead and cadmium industrial wastewater.
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
Energy Advances
·
2024
·Vol. 3
·期 5
·1111-1120
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IF 3.2
Pengwei Liu,Shouyan Sun,Tongfei Wang,Xiaojuan Shen,Maiyong Zhu
Considering its integration with other electronics, three-dimensional (3D) silicon with a large surface area is an attractive electrode substrate for supercapacitors (SCs). However, the poor silicon surface stability as well as the corresponding complicated and expensive protective fabrication process impede the practical applications of silicon-based SCs. In this work, a novel electrode was developed with a simple and facile solution method, where electrodeposited Ni particles served as the current collector layer (CC-layer) and the composite of poly(3,4-ethylenedioxythiophene) (PEDOT) and manganese dioxide (MnOx) prepared via the one-step co-electrodeposition method worked as active materials. The compact layer generated from Ni particles and PM was tightly wrapped around SiNWs, protecting the silicon surface from oxidation/corrosion. The deposition time of the Ni particles and PM was investigated. To further improve the electrochemical performance of the electrode, Pt nanoparticles (NPs) were introduced into the PM layer. The NP introduction not only enhanced the conductivity of the electrode but also made the surface become more hydrophilic, favoring the ion/charge transport. Benefiting from the large surface areas of SiNWs, the high conductivity of the CC-layer generated from the Ni particles, the high-capacity of PM and the hydrophilic surface resulting from Pt decoration, the synthesized NSi@PM–Pt electrode demonstrates a high areal specific capacitance of 207.43 mF cm−2 at 1 mA cm−2. The symmetric device delivers a maximum energy density of 0.006 mW cm−2 with a good stability retention up to 94.6% over 5000 cycles. The results afford a promising solution strategy to prepare high-performance silicon-based SCs with a simple, facile and cost-effective method.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
FUEL
·
2017
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IF 4.601
Dongjing Liu,Weiguo Zhou,Jiang Wu
CuO-based and MnO x -based sorbents modified with Ce and La using sol-gel method, were employed for elemental mercury removal at 120–240 °C. The Hg 0 removal activity of Mn 2 O 3 /ZSM-5 can be significantly enhanced by doping 50 at.% Ce or 10 at.% La, the Hg 0 removal efficiency increased by 94% and 71%, respectively. The Hg 0 removal ability of CuO/ZSM-5 subtly improved by addition of 50 at.% Ce or 10 at.% La, the Hg 0 removal efficiency ascended only by 6% and 18%, respectively. The XPS results revealed that Hg 0 transformed to HgO, and CuO (or Mn 2 O 3 ) was reduced to Cu 2 O (or Mn 3 O 4 ), which is in agreement with Mars-Maessen mechanism.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
CATALYSIS LETTERS
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2023
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IF 2.8
Chen Yao,Li Shuyue,Li Yuchao,Zheng Yanxia,Zuo Cuncun,Ge Tingting,Xu Rui,Huang Haofei,An Jiutao
Nano-Au particles are commonly used as an active component in oxidation esterification reactions. To inhibit the agglomeration of nano-Au particles, a series of highly stable Au@CeO 2 /MnO x core–shell structured catalysts were synthesized using inverse microemulsion technology for the oxidative esterification to prepare methyl methacrylate (MMA). The core–shell structured catalysts were prepared by using two different surfactants (CTAB and CO-520) and adjusting the molar ratio of water to oil (ω). XRD, Raman, N 2 adsorption, ICP−MS, TEM, UV–vis, FT-IR, XPS, and H 2 -TPR were applied to characterize the samples. The nano-Au particles were encapsulated by CeO 2 , forming a core–shell structure confirmed with TEM. The Au@CeO 2 /MnO x -C-ω = 10 catalyst prepared with CTAB as the surfactant has the best activity. The Au@CeO 2 /MnO x -C-ω = 10 catalyst has the highest hydrogen consumption and Ce 3+ content, indicating that the catalyst has the strongest interaction among Ce, Au, and Mn and more active oxygen. Active oxygen is beneficial to methanol activation and hemiacetal dehydrogenation, accelerating the formation of esters. The active oxygen content, Ce 3+ content, and H 2 consumption were correlated with the catalytic performance positively. After the catalyst was reused 10 times, the activity remained unchanged and the Au nanoparticles did not agglomerate due to the core–shell structure. Graphical Abstract
研究领域:
催化化学
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材料科学
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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 38
·17984-17998
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IF 3.3
Si Duan,Guihong Lan,Xiaoting Yang,Yongqiang Liu,Haiyan Qiu,Bo Xu,Yuan Gao,Zhuang Xie
Antibiotic contamination has become one of the most pressing problems in the field of water purification. Using nano-graphite (nano-G) as a carbon carrier, a ZrO2–MnOx/nano-G composite electrode with high catalytic activity was prepared by a hot pressing method based on MnOx/nano-G prepared by a sol–gel method. The results showed that the ZrO2–MnOx/nano-G electrode reduces charge transfer resistance while improving surface oxygen desorption ability. MnOx can catalyze the two-electron reduction of O2 to produce H2O2, which can then be converted to ˙OH and ˙O2−. Thereafter, the results of free radical capture experiments confirmed that ˙O2− played a significant role in the electrocatalytic degradation of tetracycline hydrochloride (TC) by a ZrO2–MnOx/nano-G composite electrode. Furthermore, the abundant hydroxyl groups on the surface of nano-G and ZrO2 particles can be used as active sites for catalyzing the Mn3+/Mn4+ redox reaction, resulting in the generation of additional free radicals. The high-efficiency electrocatalytic degradation of TC was achieved through the synergistic action of the three. Under optimal reaction conditions, the degradation rate of TC reached 93% after 120 min of electrolysis. ZrO2–MnOx/nano-G displayed satisfactory stability following 10 cycles of degradation experiments. Finally, the potential TC degradation pathway was investigated using liquid chromatography-mass spectrometry (LC-MS) and density functional theory (DFT), and the degradation mechanism was clarified.
研究领域:
环境科学
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材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2020
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IF 10.652
Jingheng Gao,Yifei Xiong,Qian Zhang,Yiwen Jiang,Jing Wang,Sibei Zou,Mingli Fu,Junliang Wu,Yun Hu,Daiqi Ye
MnO x -CeO 2 composite catalysts have attracted interest from all over the world as promising catalysts for carbon black oxidation. The contact between carbon black and catalyst, and the surface physicochemical properties of the catalyst, are the main factors in carbon black oxidation, while the contact is a basic one affecting the ignition of the oxidation. In this work, MnO x -CeO 2 catalysts with different geometric morphologies (nanorod and nanoparticle) are prepared to determine the effect of geometric morphology on the contact probability between catalysts and carbon black. Compared with the nanorod catalyst, nanoparticle catalyst is significantly advanced in catalytic activity (T 10 = 314 °C, T 50 = 346 °C, T 90 = 383 °C) and relative contact probability (9.549, compared to the 7.639 of nanorod catalyst, according to the 3D geometric modeling). O 2 -TPD, H 2 -TPR, and In-situ UV Raman experiments reveal that the concentration of surface intrinsic oxygen vacancy of the two catalysts are approximative. The consumption of oxygen vacancy is based on the active sites provided, which is relative to the morphology. The better consumption results in better utilization of intrinsic active oxygen species in nanoparticle sample. This finding proves the correlation between contact probability and carbon black catalytic activity, and witnesses that the consumption efficiency of surface intrinsic oxygen vacancy is an initial factor in carbon black oxidation.
研究领域:
催化化学
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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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2025
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IF 9
Caiyi Jiang,Peng Tang,Xiaolin Shi,Li Yang,Xingyong Liu,Bo Xing,Guo Yang,Yang Luo,Dongzheng Wang,Xiaoyu Zhao
Due to high efficiency and durability, Polyvinylidene Fluoride (PVDF) membranes are promising for their application in wastewater purification. However, they still inevitably face the challenge of membrane clogging problem, restricting separation and anti-fouling performance. Herein, a novel N-MnO x @PVDF membrane with high catalytic ozonation ability was synthesized using the blending non-solvent-induced reverse transfer method, evidenced by X-ray diffraction, Fourier transform infrared spectrometer, and X-ray photoelectron spectroscopy. Compared with pristine PVDF, N-MnO x @PVDF has better hydrophilicity and reasonable pore structure, resulting in higher permeability and anti-fouling properties. After in-situ catalytic ozonation cleaning, the Flux Recovery Ratio ( FRR ) increases from 72.1% to 99.8%, and the irreversible pollution rate ( R ir ) decreases from 31.9% to 0.13%. Meanwhile, the high stability and reusability can be demonstrated from high Total Organic Carbon (TOC) removal efficiency of humic acid (HA, 93%), high FRR (94%), and low R ir (4.3%) after consecutive cycles filtration experiments. In addition, further mechanistic insights are verified by 3D-excitation Emission Matrices (EEM) and Electron Paramagnetic Resonance (EPR) characterization, demonstrating that the removal of irreversible contaminants can be mainly ascribed to indirect oxidation of 1 O 2 , and their possible generation pathway is also proposed. This study provides valuable insights into the development of advanced antifouling membranes.
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
APPLIED CATALYSIS B-ENVIRONMENTAL
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2017
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IF 9.446
Hui He,Xueting Lin,Shujun Li,Zeng Wu,Jingheng Gao,Junliang Wu,William Wen,Daiqi Ye,Mingli Fu
Surface species and oxygen vacancies were studied in MnO x (0.4)-CeO 2 toward repeated soot oxidation. MnO x (0.4)-CeO 2 catalysts prepared by the citric acid complex method were repeatedly used in a 10% O 2 /Ar gas flow and showed favorable activity and satisfactory durability toward soot oxidation. X-ray diffraction (XRD), N 2 adsorption/desorption, Electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS) and in situ visible/UV Raman characterization methods were utilized to investigate the structural features of fresh and reused catalysts. The irreversible conversion of high valence manganese species as well as the reduction of Frenkel-type oxygen vacancies and lattice oxygen could be clearly observed in the reused samples, which were associated with the slight deactivation. Spectators and participators were two existing forms of Frenkel-type oxygen vacancies. It was noteworthy that the participators almost fully regenerated after each reaction cycle, which ensured the ability to activate O latt in repeated soot oxidation process. Therefore, the catalysts maintained favorable activity and satisfactory durability, which was mainly because the relatively stable level of participators.
研究领域:
催化化学
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环境催化
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材料化学
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表面科学
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能源化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2020
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IF 4.65
Fu Yang,Xu Hu,Shuying Gao,Xianfeng Liu,Shijian Zhou,Yan Kong
Herein, we report a facile synthetic method enabling the synchronously activated decoration of the inner core and mesoporous outer shell of monodispersed Fe 3 O 4 @meso-silica using in situ implanted MnO x . This approach can maintain the catalytic activity of the internal core without loss of its inherent magnetic properties even when undergoing calcination . The developed catalyst exhibits a well-defined core-shell configuration with a MnO x coating on an Fe 3 O 4 internal core and a MnO x -modified mesoporous outer shell, obtained via only a one-pot output cycle. The thin MnO x coating layer prevents excess oxidation of the unoxidized Fe 3 O 4 core during the annealing process. Additionally, the mesopores in the coated silica were synchronously functionalized by the assistance of dodecylamine (DDA) as surfactant because of the coordination effect of Mn 2+ and DDA molecules. The optimal nanocatalyst exhibits improved catalytic activity for styrene oxidation and recoverability due to its magnetic-responsive properties, in contrast to postsynthesized and shell-only functionalized catalysts.
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
FUEL
·
2021
·
IF 6.609
Jiaqi Si,Weidong Sun,Guofeng Zhao,Yong Lu
The MnO x -Na 2 WO 4 catalyst for oxidative coupling of methane (OCM) is highly attractive but its high light-off temperature (>800 °C) is a major obstacle for commercialization. In-depth understanding of reaction light-off relevant chemistry is particularly desirable. We explored the OCM light-off over several metal-oxide-supported MnO x -Na 2 WO 4 catalysts. As CH 4 conversion above 15% with acceptable C 2-3 selectivity is considered as the sign of OCM light-off, support-dependent OCM light-off is clearly observed over MnO x -Na 2 WO 4 supported on SnO 2 (660 °C), TiO 2 (670 °C), MgO (690 °C), and ZnO (720 °C), being tightly linked with the redox rate of Mn 3+ (or Mn 4+ ) ↔ Mn 2+ cycle governed by support oxides.
研究领域:
化学工程
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催化科学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
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2013
·Vol. 1
·期 31
·8978-8983
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IF 0
Liqun Ye,Xiaodi Liu,Qiang Zhao,Haiquan Xie,Ling Zan
Charge separation is very important for increasing the activity of semiconductor-based photocatalysts. Here we show that the main active species of BiOI are photo-induced holes, rather than ˙OH and O2˙−, under visible light irradiation. Based on this finding, the cocatalyst MnOx was used to enhance the transfer of the photo-induced holes, resulting in much higher photocatalytic activity, compared with the photocatalyst without MnOx. MnOx–BiOI heterogeneous nanostructure photocatalysts have been prepared by photo-deposition in Mn(NO3)2 solution, and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and photoluminescence (PL) spectroscopy. As-prepared MnOx–BiOI exhibited higher photoactivity than BiOI and Pt–BiOI for the degradation of Rhodamine B (RhB) dye under visible light irradiation. The PL spectrum showed that MnOx enhances the separation efficiency of the photo-induced electrons and holes of BiOI. Finally, BiOI was selectively combined with a deriving-hole-type cocatalyst to enhance the photocatalytic activity, and the reason for the cocatalyst selectivity is also discussed. This finding may be useful in bismuth-based photocatalysts to construct highly efficient solar energy conversion systems.
研究领域:
材料科学
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光催化技术
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环境科学
✓ 已验证
DOI
危险品化学品经营许可证（带存储）