CHEMOSPHERE
·
2023
·
IF 8.8
Qiong Wu,Chunying Dong,Maoxiang Chen,Yu Zhang,Meiqiang Cai,Yan Chen,Micong Jin,Zongsu Wei
In this study, SiO 2 -composited biochar decorated with Fe/Mn was prepared by co-pyrolysis method. The degradation performance of the catalyst was evaluated by activating persulfate (PS) to degrade tetracycline (TC). The effects of pH, initial TC concentration, PS concentration, catalyst dosage and coexisting anions on degradation efficiency and kinetics of TC were investigated. Under optimal conditions (TC = 40 mg L −1 , pH = 6.2, PS = 3.0 mM, catalyst = 0.1 g L −1 ), the kinetic reaction rate constant could reach 0.0264 min −1 in Fe 2 Mn 1 @BC-0.3SiO 2 /PS system, which was 12 times higher than that in the BC/PS system (0.00201 min −1 ). The electrochemical, X-ray diffractometer (XRD), Fourier transform infrared spectrum (FT-IR) and X-ray photoelectron spectroscopy (XPS) analysis showed that both metal oxides and oxygen-containing functional groups provide more active sites to activate PS. The redox cycle between Fe(II)/Fe(III) and Mn(II)/Mn(III)/Mn(IV) accelerated the electron transfer and sustained the catalytic activation of PS. Radical quenching experiments and electron spin resonance (ESR) measurements confirmed that surface sulfate radical (SO 4 •− ) play a key role in TC degradation . Three possible degradation pathways of TC were proposed based on high-performance liquid chromatography coupled with high-resolution mass spectrometry (HPLC-HRMS) analysis, the toxicity of TC and its intermediates was analyzed by bioluminescence inhibition test. In addition to the enhanced catalytic performance, the presence of silica also improved the stability of the catalyst, as confirmed by cyclic experiment and metal ion leaching analysis. The Fe 2 Mn 1 @BC-0.3SiO 2 catalyst, derived from low-cost metals and bio-waste materials, offer an environmentally friendly option to design and implement heterogenous catalyst system for pollutant removal in water.
研究领域:
环境科学
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污染治理
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材料科学
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产品关联
DOI
PubMed
高影响因子
Catalysis Science & Technology
·
2023
·Vol. 13
·期 10
·3147-3157
·
IF 5
Hange Wang,Wen Chen,Wei Jin,Yueli Liu
SCR technology is considered to be the most effective method for denitrification. However, the low NOx conversion rate of the current catalysts at low temperatures limits their further application. Herein, Sn-doped modified CoAl-LDH carriers are synthesized by a hydrothermal method, and the typical hexagonal sheet structure of the MnOx(0.25)/CoSn3Al-LDO catalyst achieves 100% NO conversion at a wide range of 120–330 °C with a GHSV of 30 000 h−1, and the 100% NO conversion may be maintained at 200 °C for 30 h. After the introduction of 150 ppm SO2 at 200 °C, the NO conversion of the MnOx(0.25)/CoSn3Al-LDO catalyst is maintained at 73.4%, which is greatly improved compared with those of CoAl-LDO and MnOx(0.25)/CoAL-LDO catalysts (64.8% and 38.6%, respectively). The active components such as MnOx and Co3O4 are highly dispersed in the MnOx(0.25)/CoSn3Al-LDO catalyst. Sn doping increases the ratios of Mn4+/Mn3+ and Co3+/Co2+ as well as the adsorbed oxygen amount on the catalyst surface, and improves the redox capacity of the catalyst and increases the number of acid sites, resulting in the excellent low-temperature NH3-SCR performance of MnOx(0.25)/CoSn3Al-LDO.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2022
·Vol. 18
·期 13
·2106863
·
IF 15.153
Jie Huang,Yeqing Chen,Pengpeng Rao,Zongming Ni,Xueying Chen,Jie Zhu,Chen Li,Gaoyang Xiong,Ping Liang,Xin He,Songnan Qu,Jun Lin
Carbonized polymer dots (CPDs) have received tremendous attention during the last decade due to their excellent fluorescent properties and catalytic performance. Doping CPDs with transition metal atoms accelerates the local electron flow in CPDs and improves the fluorescent properties and catalytic performance of the CPDs. However, the binding sites and the formation mechanisms of the transition-metal-atom-doped CPDs remain inconclusive. In this work, Mn 2+ -ion–doped CPDs (Mn-CPDs) are synthesized by the hydrothermal method. The Mn 2+ ions form Mn O bonds that bridge the sp 2 domains of carbon cores and increases the effective sp 2 domains in the Mn-CPDs, which redshifts the fluorescence emission peak of the Mn-CPDs slightly. The Mn 2+ ions form covalent bonds in the CPDs and remedy the oxygen vacancies of the CPDs, which cuts off the non-radiative–recombination process of the Mn-CPDs and increases the quantum yield of the Mn-CPDs to 70%. Furthermore, the Mn O bonds accelerate the electron flow between adjacent sp 2 domains and enhances the electron transport in the Mn-CPDs. Thus, the Mn-CPDs demonstrate excellent catalytic performance to activate hydrogen peroxide (H 2 O 2 ) and produce hydroxyl radicals (•OH) to degrade methylene blue (MB) and rhodamine B (RhB).
研究领域:
材料科学
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纳米技术
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催化
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光化学
✓ 已验证
DOI
高影响因子
NANO
·
2019
·
IF 1.293
Zhenping Liu,Xianfeng Wang,Jingzhou Hou,Danqun Huo,Changjun Hou
An innovative phosphorescence probe based on Mn-doped ZnS quantum dots (Mn:ZnS QDs) was developed for selective detection of chloramphenicol (CAP) via inner-filter effect (IFE). Mn:ZnS QDs were synthesized by water method and modified with L-Cysteine for better stability, and the average diameter of the nanometer particle was 3.8 nm. With the excitation wavelength at 289 nm, the strong phosphorescence of Mn:ZnS QDs can be emitted at 583 nm. The excitation spectrum of Mn:ZnS QDs was substantially overlapped with the absorption spectrum of the target CAP. The excited light of Mn:ZnS QDs can be absorbed partially by CAP when they coexist, the phosphorescence intensity decreased with the increasing concentration of CAP, and it has a good linear relationship. Under optimal conditions, the linear relational concentration range achieved four orders of magnitude from 25 to 1 . 2 × 1 0 5 ng ⋅ mL − 1 ( R 2 = 0 . 9 9 9 ), with a detection limit (LOD; S ∕ N = 3 ) down to 0.81 ng ⋅ mL − 1 . The simple, rapid and low cost IFE phosphorescent probe exhibited satisfactory recoveries ranging from 88.9% to 98.5% for CAP analysis in spiked honey, which shows a potential for routine screening of CAP in ensuring the food safety.
研究领域:
分析化学
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食品安全
·
生物医学
✓ 已验证
产品关联
DOI
高影响因子
ChemNanoMat
·
2018
·Vol. 4
·期 5
·487-495
·
IF 3.173
Zhinian Li,Shenliang Wang,Wei Hong,Shihui Zou,Liping Xiao,Jie Fan
Graphical Smart screens : An intelligent approach was developed to screen Na−Mn−W/SiO 2 catalysts for the oxidative coupling of methane (OCM). Effective composition regions other than the standard composition were successfully excavated. The wide range of the optimal composition allowed a fluctuation of composition during the reaction, which secured its excellent stability in the OCM reaction. Optimizing the performance and understanding the mechanism of metal oxide catalysts in the oxidative coupling of methane (OCM) is one of the most important projects in industrial catalysis. Here, we report an intelligent approach to screen Na−Mn−W/SiO 2 catalysts for the OCM reaction via ink-jet printing and multidimensional group testing. The ink-jet-printing-assisted (IJP-A) synthetic methodology ensured a fast synthesis of 1536 catalysts that were evaluated in 24 tests via a multidimensional group testing strategy (m-GT). After two-round synthesis-and-screening processes, several excellent groups with different composition space were screened out. Among the excellent catalysts, the OCM performance of Na−Mn−W/SiO 2 catalyst with higher Na, Mn and W content (G3 and G7) was less sensitive to its constituent than that of Na−Mn−W/SiO 2 catalyst with lower Na, Mn and W content (G1). These results indicated the sensitivity of performance to its Na, Mn and W content decreased in larger Na, Mn and W spaces, consistent with the complex homogeneous/heterogeneous reaction mechanism and multi-active sites. A series of Na−Mn−W/SiO 2 formulas with good performance also provide a reasonable explanation to its excellent stability for the OCM reaction. In addition, this intelligent optimization in total space offers a pathway to study the multicomponent metal oxide catalyst in the OCM reaction.
研究领域:
化学工程
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催化
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2016
·Vol. 18
·期 8
·1384-1392
·
IF 3.849
S. Ding,X. F. Yang,T. T. Deng,E. H. Song,Z. J. Ma,S. Ye,M. M. Wu,Q. Y. Zhang
Solid-solution phase K(Mn,Zn)F3 mesoporous microspheres have been successfully prepared via a simple one-pot hydrothermal method by using citrate ions as a chelating agent. Effects of the reaction time on the phase transformation and morphological evolution of the K(Mn,Zn)F3 microspheres have been carefully investigated. The results revealed that the hierarchical mesoporous spherical structures with a solid-solution phase were formed from a core–shell structure with mixed phases via the nanoscale Kirkendall effect. It is noted that Yb3+/Er3+-codoped K(Mn,Zn)F3 microspheres exhibit intense single-band red up-conversion emission with environmental responsivity upon excitation using a 980 nm laser diode, indicating a promising potential biomedical application for drug delivery.
研究领域:
材料科学
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生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2019
·Vol. 26
·期 14
·14350-14361
·
IF 2.914
Wu Kang,Si Xiongyuan,Jiang Jin,Si Youbin,Sun Kai,Yousaf Amina
In this study, a novel Fe–Mn binary oxide (FMBO), which combined the oxidation capability of iron and manganese oxides, was constructed to remove sulfamethoxazole (SMX) effectively using the simultaneous co-precipitation and oxidation methods, and the reaction products were probed by liquid chromatography-mass spectrometry (LC/MS). Particularly, FMBO-mediated transformation mechanisms of SMX were explored using radical scavengers and electron paramagnetic resonance (EPR). Results indicated that the best removal efficiency was obtained at a pH of 4.0, with the H 2 O 2 of 6.0 mmol/L and the FMBO dosage of 2.0 g/L, giving 97.6% removal of 10 mg/L SMX within 60 min. More importantly, we found that the hydroxyl (•OH) radicals generated by FMBO through Fenton-like reaction were responsible for the SMX oxidation. EPR studies were confirmed that the peak intensities of hydroxyl adduct decreased remarkably with increasing pH values. Moreover, the four SMX degradation intermediate products were detected by LC/MS and a reaction pathway for the possible mineralization of SMX, with •OH radicals as the main oxidant, was proposed. These findings provide a novel insight into the removal of SMX by FMBO-mediated radical reactions in aquatic environments. Moreover, this research suggested that FMBO can act as an efficient catalyst to remove SMX in hospital wastewater.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
·
2022
·
IF 6.47
Xinbo Zhu,Haiping Xiong,Jin Liu,Yuting Gan,Zitan Xu,Chunlin Zhou,Yaolin Wang,Ye Jiang,Xin Tu
In this work, Fe–Mn based ternary catalysts (Fe–Mn-X, X = Ce, Co and Cu) were evaluated in the plasma-catalytic oxidation of ethylene oxide (EO) using a cylindrical dielectric barrier discharge (DBD) reactor. The addition of transition metal dopants to the Fe–Mn catalyst significantly improved the performance of plasma-catalyzed EO oxidation compared to the reaction using plasma only and the Fe–Mn catalyst. The highest EO conversion (91.9%) and CO 2 selectivity (78.9%) were obtained over the Fe–Mn–Co catalyst at a specific energy input (SEI) of 730.2 J l −1 . Moreover, the presence of water vapor improved EO conversion and CO 2 selectivity in the relative humidity (RH) range of 0–60%, while further increasing the RH to 80% reduced EO conversion. The interactions between Fe, Mn and dopants increased the specific surface area and pore volume of the Fe–Mn-X catalyst, while maintaining the crystalline structure of the catalysts. The presence of the dopants enhanced the reducibility of the Fe–Mn-X catalysts and produced more surface adsorbed oxygen (O ads ) on the catalyst surfaces. Moreover, the interactive effects among the Fe, Mn and dopants facilitated the plasma-catalytic oxidation reactions via enhanced surface reactions. The coupling of plasma with the Fe–Mn–Co catalyst reduced the formation of organic by-products in the plasma-catalyzed oxidation of EO.
研究领域:
环境科学
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催化化学
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材料科学
✓ 已验证
DOI
高影响因子
Catalysts
·
2024
·Vol. 14
·期 7
·397
·
IF 3.8
Yuxuan Zhang,Ruibo Wei,Lin Yang,Jinming Ge,Feiyang Hu,Tingting Zhang,Fangyin Lu,Haiwang Wang,Jian Qi
The low-temperature oxidation of methane gas in coal mine exhaust gas is important for reducing the greenhouse effect and protecting the environment. Unfortunately, the carbon–hydrogen bonds in methane molecules are highly stable, requiring higher reaction temperatures to achieve effective catalytic oxidation. However, metal oxide-based catalysts face the problem of easy sintering and the deactivation of active components at high temperatures, which is an important challenge that catalysts need to overcome in practical applications. In this work, a series of Mn-Co3O4active components were grown in situ on ZSM-5 zeolite with mesoporous pore structures treated with an alkaline solution via a hydrothermal synthesis method. Due to the presence of polyethylene glycol as a structure-directing agent, manganese can be uniformly doped into the Co3O4lattice. The large specific surface area of ZSM-5 zeolite allows the active component Mn-Co3O4to be uniformly dispersed, effectively preventing the sintering and growth of active component particles during the catalytic reaction process. It is worth mentioning that the Mn-Co3O4/meso-ZSM-5-6.67 catalyst has a methane conversion rate of up to 90% at a space velocity of 36,000 mL·g−1·h−1and a reaction temperature of 363 °C. This is mainly due to the mesoporous ZSM-5 carrier with a high specific surface area, which is conducive to the adsorption and mass transfer of reaction molecules. The active component has an abundance of oxygen vacancies, which is conducive to the activation of reaction molecules and enhances its catalytic activity, which is even higher than that of noble metal-based catalysts. The new ideas for the preparation of metal oxide-based low-temperature methane oxidation catalysts proposed in this work are expected to provide new solutions for low-temperature methane oxidation reactions and promote technological progress in related fields.
研究领域:
环境科学
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催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2019
·
IF 3.131
Boqiong Jiang,Beilong Lin,Zhiguo Li,Shuang Zhao,Ziying Chen
A series of Mn/TiO 2 catalysts were prepared by ultrasonic spray pyrolysis (USP) method for selective catalytic reduction (SCR) of NOx from flue gas at low temperatures. The highest activity of Mn/TiO 2 was obtained with a Mn/Ti ratio of 0.5. When Fe was doped into Mn(0.5)/TiO 2 , the NOx conversion rate on Fe(0.05)-Mn(0.5)/TiO 2 was increased by approximately 10 % at 120–180 °C. The samples were characterized by XRD , SEM , H 2 -TPR, and N 2 adsorption analyses. Results revealed that Mn(0.5)/TiO 2 with Mn/Ti ratio of 0.5 presented the lowest crystallinity , the highest surface area, and the highest redox ability. Although the surface area was significantly decreased by Fe doping, it also reduced the crystallinity and crystal size of the catalysts, thereby increasing the O concentration on the surface of catalyst. Moreover, Fe(0.05)-Mn(0.5)/TiO 2 displayed a higher redox ability than the other catalysts. At 120–240 °C, the activation energy decreased from 27.65 kJ/mol on Mn(0.5)/TiO 2 to 14.46 kJ/mol on Fe(0.05)-Mn(0.5)/TiO 2 , thereby facilitating the activation of the reaction on Fe(0.05)-Mn(0.5)/TiO 2 . Despite that the NO and NH 3 adsorptions were lower on Fe(0.05)-Mn(0.5)/TiO 2 than on Mn(0.5)/TiO 2 , the intermediates on Fe(0.05)-Mn(0.5)/TiO 2 , particularly nitrates, were easily activated to participate in the reaction, leading to increasing catalytic activity.
研究领域:
环境科学
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2019
·
IF 14.229
Ling Zhang,Yiquan Xie,Yiwen Jiang,Yaobin Li,Chunying Wang,Shichao Han,Huimin Luan,Xiangju Meng,Feng-Shou Xiao
Catalytic combustion at low temperature has been considered as an effective route for removal of indoor HCHO pollutant, and conventional catalysts are supported noble metal nanoparticles, which are costly for wide applications. Solution of this issue is to use relatively low metal catalysts. Herein, we report that Mn-promoted Ag catalyst supported on pure silica Beta zeolite with a good hydrophobicity is very active for catalytic combustion of HCHO. By optimizing the loadings of Ag and Mn, it is found that 10 wt% Ag with 8 wt% Mn (10 %Ag8 %Mn/Beta-Si) exhibits highest activity, giving the complete HCHO conversion at around 45 °C, which steadily outperform the temperatures (70–145 °C) for full oxidation of HCHO reported previously. The choice of Ag loading with 10 wt.% is due to the highest exposed surface of Ag sites, and the use of Mn loading with 8 wt% is assigned to the balance of density and mobility for active oxygen species in the catalysts. The strategy combining the hydrophobic supports with optimized active oxygen species might offer an alternative way to develop highly efficient heterogeneous catalysts for the removal of air pollutants in the future.
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
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Jinghang Sun,Zhongmin Fang,Xianfa Zhang,Linjie Li,Xiaodan Zhao
Advanced oxidation processes (AOPs) based on sulfite activation have been demonstrated to achieve cost-effective and highly efficient abatement of organic pollutants. In this work, the manganese-doped γ-Fe 2 O 3 catalyst (Mn-γ-Fe 2 O 3 ) is constructed based on the properties of Mn(II) with surface oxygen vacancy regulation and as an active site for sulfite activation. The increase of the Mn(II) doping ratio is favorable for the generation of surface oxygen vacancy with the content being enhanced more than two times when the Mn(II) doping ratio is 0.09 compared with that of γ-Fe 2 O 3 . The iohexol (IOX) abatement efficacy by sulfite activation with Mn-γ-Fe 2 O 3 is positively correlated with the oxygen vacancy content, in which SO 4 •− is the major free radical responsible for IOX degradation and HO • plays a secondary role. The presence of surface oxygen vacancy on the Mn-γ-Fe 2 O 3 exhibits low electrochemical resistance. The theoretical calculations support the enhancement of the electron transfer between Mn-γ-Fe 2 O 3 and sulfite with more negative adsorption energy and strong interaction of iron and manganese atoms. By analyzing the valence variation before and after the reaction, both > Mn(II) and > Fe(III) can participate in the acceleration of sulfite autoxidation process to generate radicals. Application of surface oxygen vacancy enriched Mn-γ-Fe 2 O 3 for sulfite activation exhibits good adaptability to different real water matrices and thus have some potential for practical applications.
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