SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Ke Li,Yibing Sun,Jiawei Zhou,Xinyue Zhang,Hongchao Li,Zhichao Yang
The combination of transition metal oxides with carbon-based materials is a promising strategy for constructing efficient catalysts for peroxymonosulfate (PMS) activation to degrade aqueous organic contaminants. However, the complex heterostructure of the composites often hinders the identification of the actual reactive species responsible for pollutant degradation. In this study, we integrate Mn 3 O 4 into N-doped graphite (NG) to elucidate the mechanisms involved in the Mn-NG composite mediated PMS activation process. The Mn-NG/PMS system shows excellent performance in oxidizing bisphenol A (BPA) over a wide pH range (3.4 to 9.4) and in the presence of co-existing substrates. Mn sites in Mn 3 O 4 are responsible for the activation of PMS, and the NG matrix enhances the dispersion of Mn in the Mn-NG composite. Multiple experimental results indicate that free radicals (i.e., hydroxyl radicals (HO • ) and sulfate radicals (SO 4 •− )) are not generated, and surface reactive Mn(IV) is proposed as the primary reactive species for BPA oxidation. This study provides new insights into understanding the role of Mn oxides in carbon-based composites in PMS activation for degradation of organic pollutants.
研究领域:
环境科学
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材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2022
·Vol. 12
·期 13
·4157-4168
·
IF 6.177
Rui Huang,Li Luo,Wei Hu,Zhixin Tang,Xing Ji,Leqi Chen,Zhaoshi Yu,Yunhuai Zhang,Dan Zhang,Peng Xiao
Mn-Based metal oxides have shown promising performance in catalytic oxidation of toluene due to the mixed Mn3+ and Mn4+ valences on the surface. Herein, a series of Co–Mn catalysts were synthesized by adjusting the redox precipitation pH to explore the effect of pH on Mn3+, Mn4+ and the surface adsorbed oxygen species when applied for toluene combustion. The Co–Mn-12 catalyst fabricated at pH = 12 displayed excellent catalytic activity and stability for the toluene oxidation of which the T90 at 20 000 mL g−1 h−1 was 208 °C. The toluene conversion could be maintained at around 100% even with the introduction of 10 vol% H2O at 230 °C. We found the appropriate pH for the promotion of the generation of more Mn3+ and Co3+ ions, which were conducive to the formation of oxygen vacancy clusters and resulted in more adsorbed oxygen species generated on the catalyst surface. Moreover, in situ DRIFTS spectra displayed that the existing high valence metal ions and oxygen vacancy clusters facilitated the CC breaking of aromatic rings and the formation of maleic anhydride in the oxidation process. Therefore, Co–Mn-12 demonstrated the best catalytic activity and water-resistance, illustrating that it is an efficient potential industrial catalyst for removing toluene.
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
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Qin Liu,Peipei Dang,Guodong Zhang,Hongzhou Lian,Ziyong Cheng,Guogang Li,Jun Lin
Mn2+-doped luminescent materials play a significant role in a variety of fields, including modern lighting, displays, and imaging. Mn2+ exhibits a broad and adjustable emission, hinging on the local environment of the crystal field and the interaction of the 3d5 electrons. However, it is still a challenge to realize the precise control of the emission of Mn2+ ions due to site-prior occupation in a specific lattice. Here, the formation of Mn–Mn dimers is proposed to be an effective strategy to design a novel red emission. Multimode emitters in Mn2+-activated AZn4(PO4)3 (A = K, Rb, and Cs) with unique [Zn4PO12] chains and [ZnOn] groups are observed to achieve regular green and unusual red emissions. KZn4(PO4)3:Mn2+ shows broad dual emissions at 542 and 608 nm, attributed to [MnO4] and [Mn2O7] dimers, respectively. While K is replaced with Rb and Cs, the Zn ions form [ZnO4] tetrahedra and [ZnO5] octahedra. RbZn4(PO4)3:Mn2+ exhibits a broad red emission at 618 nm, ascribing to [Mn2O7] and [Mn2O8] dimers. CsZn4(PO4)3:Mn2+ also displays a broad orange-red emission at 608–620 nm with increasing doping levels, deriving from energy transfer from [MnO5] to [Mn2O7] and [Mn2O8] dimers. This work provides a framework for creating novel red emissions from Mn2+-doped luminescent materials.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2016
·
IF 4.035
Songqing Chen,Xingxiu Qin,Weixi Gu,Xiashi Zhu
Ionic liquids-β-cyclodextrin polymer (ILs-β-CDCP) was attached on Fe 3 O 4 nanoparticles to prepare magnetic solid phase extraction agent (Fe 3 O 4 @ILs-β-CDCP). The properties and morphology of Fe 3 O 4 @ILs-β-CDCP were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction(XRD), size distribution and magnetic analysis. A new method of magnetic solid phase extraction (MSPE) coupled to ICP-OES for the speciation of Mn(II)/Mn(VII) in water samples was established. The results showed that Mn(VII) and total manganese [Mn(II)+Mn(VII)] were quantitatively extracted after adjusting aqueous sample solution to pH 6.0 and 10.0, respectively. Mn(II) was calculated by subtraction of Mn(VII) from total manganese. Fe 3 O 4 @ILs-β-CDCP showed a higher adsorption capacity toward Mn(II) and Mn(VII). Several factors, such as the pH value, extraction temperature and sample volume, were optimized to achieve the best extraction efficiency. Moreover, the adsorption ability of Fe 3 O 4 @ILs-β-CDCP would not be significantly lower after reusing of 10 times. The accuracy of the developed method was confirmed by analyzing certified reference materials (GSB 07-1189-2000), and by spiking spring water, city water and lake water samples.
研究领域:
分析化学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF LUMINESCENCE
·
2023
·
IF 3.6
Wenyong Jia,Qilin Wei,Shangfei Yao,Shuaigang Ge,Chengyu Peng,Lishuang Wang,Xianci Zhong,Hui peng,Bingsuo Zou
All-inorganic ABX 3 (X = Cl,Br,I) can work as an ionic luminescence material in optoelectronic field. Here Mn-doped CsCdCl 3 hexagonal perovskite powders were synthesized and found to give bright orange-yellow colored emission at room temperature with an astonishingly quantum yield close to 100% at successful incorporation of 2.1% atomic ratio Mn ions. This enhanced emission comes from the local magnetic polaron—combined STEs with ferromagnetic Mn–Mn pair d-d transition ( 4 T 1 → 6 A 1 ) in replacement of Cd dimers in the CsCdCl 3 lattice. Compared with CsCdBr 3, this local magnetic polaron rely on the magnetic couplings, for example, in the Mn ions in the octahedral point and edge alternately connected 1-d chain and between 1-d chains, upon Mn concentrations. The magnetic coupling can modify the optical absorption edge and photoluminescence quantum yield (PLQY), and tune emission color from yellow to red. The PLQY maximum occurs at 350 K. The more Mn–Mn FM coupling in denser Mn-X octahedra face-shared chains in the bromides lead to a larger emission redshift than in the chloride. The magnetic coupling in the perovskite out of local Mn connection styles (separated, or point, edge and face shared TM ions) can determine its PLQY and emission color, which is useful in the future material design and optoelectronic or spintronic devices.
研究领域:
材料科学
·
光电学
·
自旋电子学
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固体物理学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Xiaoying Zhou,Shiyu Fang,Tiantian Zhang,Zuliang Wu,Jing Li,Wei Wang,Jiali Zhu,Junliang Wu,Daiqi Ye,Rui Han,Qingling Liu,Shuiliang Yao,Erhao Gao,Dayu Wu
The development of non-noble metal catalysts for low-temperature CO oxidation is a pivotal subject in various disciplines. In this study, an optimized Mn-doped NiO catalyst (Mn-NiO-0.5), prepared via aerosol pyrolysis with an equal molar ratio of Ni to Mn, demonstrates remarkable performance. It achieves an 82 % CO conversion at -20 °C and a 100 % conversion between 10 °C and 800 °C. The catalyst’s turnover frequency ( TOF ) for CO oxidation significantly surpasses that of previously reported noble-metal-based catalysts, underscoring its superior efficiency. Dynamic analyses suggest that the enhanced catalytic activity is a result of the unique atom burr structure, which presents an extensive surface area replete with abundant active sites. This structural feature is instrumental in maximizing the catalyst’s interaction with CO molecules. Experimental findings, corroborated by density functional theory (DFT) calculations, elucidate the mechanism of CO oxidation on the Mn-NiO-0.5 catalyst. The process is facilitated by the synergistic action of bimetallic sites, where the Ni–OH site acts as the primary adsorption point for CO. Subsequently, the CO is oxidized to bicarbonate through the interaction with the oxygen (O or O 2 ) at adjacent Mn sites. This pioneering study introduces a paradigm-shifting insight: the effectiveness of non-noble metal oxide catalysts can now compete with, and in some cases, outperform their noble metal counterparts. This breakthrough is set to transform the industry, presenting a compelling alternative to conventional noble metal catalysts and propelling the evolution of state-of-the-art environmental conservation technologies.
研究领域:
催化化学
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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
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
·
2021
·
IF 3.927
Xiao Tian,Jiaxiong Xu
The reported Ag and Mn co-doped Cu 2 ZnSnS 4 thin film has better properties than single-doped Cu 2 ZnSnS 4 . However, the role of Mn in co-doped Cu 2 ZnSnS 4 thin film is still unclear. In this paper, Ag and Mn co-doped Cu 2 ZnSnS 4 thin films with different Mn amounts were prepared by sol-gel method. The crystal phases, morphologies, element compositions, and optical properties of co-doped Cu 2 ZnSnS 4 thin films were characterized to investigate the role of Mn doping. Compared with Ag single-doped Cu 2 ZnSnS 4 thin film, after the incorporation of Mn into Ag-doped Cu 2 ZnSnS 4 , the crystallinity of Cu 2 ZnSnS 4 improves and the micro-strain and dislocation density in the crystal reduce. The valence states of Cu, Zn, Sn, S, Ag, and Mn in co-doped thin film are +1, +2, +4, −2, +1, and +2, respectively. Mn doping can make the grains on the thin film surface enlarge. The MoS 2 interface layer between Cu 2 ZnSnS 4 and Mo becomes thinner and the Urbach energy of Cu 2 ZnSnS 4 decreases after Mn doping. Therefore, Mn in the co-doped Cu 2 ZnSnS 4 thin films shows beneficial effects of enhanced structural, morphological, and optical properties of the films.
研究领域:
材料科学
·
光伏技术
✓ 已验证
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2023
·
IF 6.1
Danlei Qiao,Yixuan Zhang,Chang Su,Guoqiang Liu,Qingxiang Wang,Lei Wen
Al-doped Fe-Mn and Ni-Mn based materials with P2-type layered structure has been synthesized and tested as a positive electrode material for rechargeable sodium batteries. The modification mechanisms of Al doping in Fe-Mn and Ni-Mn based materials have been discussed. The synthesized Al-doped Ni-Mn based material Na 0.67 Mn 0.8 Ni 0.16 Al 0.04 O 2 delivers a reversible capacity of 135.1 mAh g −1 , which corresponds to 92.1% of the initial capacity with excellent cyclability for 200 cycles. What’s more, it can still remain a capacity of 96.2 mAh g −1 at a current density of 2000 mA g −1 . When the voltage range increase to 1.5 – 4.3 V, its initial discharge capacity can reach 190.3 mAh g −1 .
研究领域:
材料科学
·
电化学
·
能量存储
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2022
·Vol. 10
·期 20
·10892-10901
·
IF 14.511
Wenfei Dong,Nan Zhang,Sanxiu Li,Shixiong Min,Juan Peng,Wanyi Liu,Dongping Zhan,Hongcun Bai
The electrocatalytic reduction of CO2 using electricity produced from renewable resources is a strategy for achieving CO2 emission reduction and sustainable energy development. Further, the reaction has a large number of industrial practical applications, since CO2 can be converted to fuels via downstream chemical processing of the CO product. Herein, we successfully synthesized a low Mn-content single-atom catalyst (SAC) with Mn–N2O2 sites, covalently integrated into carbon nanosheets (Mn–NO/CNs) using a one-pot synthesis method. The Mn–NO/CN catalyst displays efficient electrocatalytic performance for the CO2 reduction reaction (CO2RR). Using an H-type electrolytic cell, the maximum CO Faraday efficiency (FE) at −0.460 V (V vs. RHE) reaches 96.0% in 0.5 M KHCO3 electrolyte. In the flow cell measurements, Mn–NO/CNs exhibits a current density of 28 mA cm−2 at a very low potential of −0.425 V (V vs. RHE) for the CO2RR with 1.0 M KOH as the mobile phase. The FECO remains above 80% even after 70 h, demonstrating the excellent durability of the catalyst even at a very low potential. The X-ray absorption spectra (XAS) and DFT calculations show that the Mn–N2O2 site is the active catalytic center, which facilitates the adsorption of CO2 and significantly lowers the free energy barrier leading to the formation of the critical intermediate *COOH. The presence of dual N and O coordinated to the single atom metal sites embedded in the 2D carbon nanosheet significantly improves catalytic activity for the reduction of CO2. Therefore, the catalytic performance of the single atom metal catalyst can be enhanced by adjusting the coordination environment.
研究领域:
电化学
·
催化
·
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Kaiting Chen,Xinyu Han,Qian Wang,Kaijie Liu,Xiangguang Yang,Yibo Zhang
The selective catalytic reduction of NO by CO (CO-SCR) presents an economical and promising approach to mitigate emissions of NO x and CO from motor vehicles. A bimetallic Rh-Mn supported catalyst Rh-Mn/CoAlO was synthesized through the reduction of citric acid and ethylene glycol, and subsequently employed in the CO-SCR reaction. Tests assessing its catalytic performance revealed that the Rh-Mn/CoAlO catalyst displayed superior CO-SCR activity, maintaining high efficiency (≥90 % at 230 °C) and stability while simultaneously reducing the usage of noble metals. Various characterization techniques, including H 2 -TPR, NO-TPD, CO-pulse, and XPS, indicated that the Rh-Mn/CoAlO catalyst possessed enhanced dispersion of noble metals. This increased dispersion ensured optimal contact between Rh and Mn, as well as the support, fostering a synergistic interaction that facilitated electron transfer. Consequently, the catalyst’s adsorption and activation capabilities for NO were significantly improved. In situ DRIFTs studies further elucidated that the catalyst primarily followed the E-R mechanism, wherein NO is adsorbed onto the catalyst surface, and subsequently, the N and O atoms generated from pyrolysis react with CO in the gas phase. The findings of this study are anticipated to offer an effective strategy for designing catalysts with exceptional low-temperature activity and high dispersibility for the reduction of NO using CO.
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
CHEMOSPHERE
·
2023
·
IF 8.8
Yuxi Liao,Peng Liu,Jun Zhang,Can Wang,Longwen Chen,Dengfeng Yan,Quanming Ren,Xiaoliang Liang,Mingli Fu,Suib Steven L.,Daiqi Ye
Increasing the contact efficiency and improving the intrinsic activity are two effective strategies to obtain efficient catalysts for soot combustion. Herein, the electrospinning method is used to synthesize fiber-like Ce–Mn oxide with a strong synergistic effect. The slow combustion of PVP in precursors and highly soluble manganese acetate in spinning solution facilitates the formation of fibrous Ce–Mn oxides. The fluid simulation clearly indicates that the slender and uniform fibers provide more interwoven macropores to capture soot particles than the cubes and spheres do. Accordingly, electrospun Ce–Mn oxide exhibits better catalytic activity than reference catalysts, including Ce–Mn oxides by co-precipitation and sol-gel methods. The characterizations suggest that Mn 3+ substitution into fluorite-type CeO 2 enhances the reducibility through the acceleration of Mn–Ce electron transfer , improves the lattice oxygen mobility by weakening the Ce–O bonds, and induces oxygen vacancies for the activation of O 2 . The theoretical calculation reveals that the release of lattice oxygen becomes easy because of a low formation energy of oxygen vacancy, while the high reduction potential is beneficial for the activation of O 2 on Ce 3+ -Ov (oxygen vacancies). Due to above Ce–Mn synergy, the CeMnO x -ES shows more active oxygen species and higher oxygen storage capacity than CeO 2 -ES and MnO x -ES. The theoretical calculation and experimental results suggest that the adsorbed O 2 is more active than lattice oxygen and the catalytic oxidation mainly follows the Langmuir-Hinshelwood mechanism. This study indicates that electrospinning is a novel method to obtain efficient Ce–Mn oxide.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Changcheng Sun,Lyumeng Ye,Peng Lu,Xianhui Yan,Jianhang Huang,Zhixiong Tang,Dongyao Chen,Chaoping Cen
The key point to broaden the operating temperature window for synergistic control of NO x and oxygenated volatile organic compounds (OVOCs) with high NO x /VOCs conversion and N 2 /CO 2 selectivity relies on development of appropriate catalysts. Herein, a silver-modified Mn/HZSM-5 catalyst was designed, which achieved an effective NO x and acetone co-removal activity and maintained over 90 % N 2 /CO 2 selectivity at a broad temperature range from 293 to 400 °C. The excellent performance of MnAg/HZSM-5 was due to large surface area, plenty of oxygen vacancies and Lewis acid sites, as well as outstanding oxygen mobility and reducibility that derived from the interactions between Mn 4+ /Mn 3+ and Ag + /Ag 0 . NO x reduction followed both Eley-Rideal and Langmuir-Hinshelwood mechanisms, while acetone hardly replaced NH 3 as a reduction agent. Acetone oxidation underwent acetone → acetate → formate → carbonate → CO 2 and H 2 O following a Mars-van Krevelen mechanism. NH 3 participated in acetone oxidation, forming amide and nitrile species, which caused catalyst deactivation and secondary pollution.
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
危险品化学品经营许可证（带存储）