JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2023
·Vol. 34
·期 24
·1-12
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IF 2.8
Qu Jing-Jing,Liu Fei,Yuan Chang-Lai,Liu Xiao,Meng Liu-Fang,Shen Nai-Rui,Ning Hui-Wang,Jiang Wei
The Mn 3+ -ions doped Ba(Mn x Bi 1− x )O 3 ( x = 0.0, 0.02, 0.04, 0.06, 0.08 and 0.1) ceramic block samples are prepared by traditional solid-state method. The phase structures of these ceramic systems are analyzed, in which the XRD analysis results show the ceramic systems can be formed the solid solutions as the relatively lower Mn-adding content of x ≤ 0.4, and the ceramic blocks appear the additional diffraction peak belonging to the MnO 2 second phase with the increase of x value (≥ 0.6). Combined with the acceptor atom-doping conduction model theory and XPS analysis results, the main conductive forms of these Ba(Mn x Bi 1− x )O 3 thermistors include in the following three kinds: the movable holes formed by the acceptor Mn-doping, the 2Bi 4+ → Bi 3+ + Bi 5+ disproportionation reaction, and the [Mn 3+ /Mn 4+ ] small polaron jump. For the electrical properties test results, the NTC thermal properties for the x = 0.02 and x = 0.06 samples are relatively superior: ρ 25 − 690 Ω cm, B 25/85 − 3150 K and ρ 25 ~ 940 Ω cm, B 25/85 − 3080 K, respectively.
研究领域:
材料科学
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电子工程
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2019
·Vol. 7
·期 6
·2845-2854
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IF 10.733
Tianshu Zhang,Jing Wang,Wentao Zhang,Chengyuan Yang,Liang Zhang,Wenxin Zhu,Jing Sun,Guoliang Li,Tao Li,Jianlong Wang
Highly efficient decontamination of naturally occurring As(III) from aqueous media remains a rigorous task for public health and ecosystem protection. As its increasingly acute toxicity and mobile characteristics than those of As(V), it is imperative to exploit a technique for the simultaneous removal and detoxication of As(III). Herein, a novel strategy involving outer and inner structural engineering of an amorphous FeMn-MOF-74 adsorbent was developed via a facile temperature-controlled crystallization method, which integrated the inner amorphous structure with low-coordinated active centers and the outer optimized metal atomic ratio with homogeneous adsorption/oxidation sites for generating the synergistic effects of As(III) removal. An appropriate Fe/Mn ratio (∼1.96) with optimized temperature (denoted as aFMM-120) endows the synergic effect of iron and high-valence manganese nodes in the framework with the highest experimental adsorption capacity of 161.6 mg g−1 among MOF-based arsenic adsorbents. Detailed characterizations through X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy demonstrated the redox behavior of Mn species and surface coordination of oxygen molecules in FeO clusters toward As(III). All these results imply that amorphous aFMM-120 is an effective adsorptive oxidation material for efficient arsenic-contaminated water remediation.
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 SURFACE SCIENCE
·
2019
·
IF 5.155
Yaqiong Gong,Yu Lin,Zhi Yang,Feixiang Jiao,Jinhui Li,Wenfei Wang
The investigation of earth-abundant, durable, and efficient bifunctional electrocatalysts for overall water splitting was critical to future renewable energy systems. Herein, flower-like Mn-doped Cu 7.2 S 4 @NiS 2 @NiS was successfully assembled on 3D nickel foam (NF) substrate via a facile two-step hydrothermal‑sulfuration method (denote as flower-like Mn 2 -CNN/NF). Benefited from unique 3D configuration with firm contact between nanoflowers and Ni foam, flower-like Mn 2 -CNN/NF electrode demonstrated a low overpotential of 252 mV to achieve a current density of 50 mA cm −2 and 24 h-long stability toward oxygen evolution reaction (OER) in 1 M KOH. For hydrogen evolution reaction (HER), a stable current density of 10 mA cm −2 at only an overpotential of 87 mV and a low Tafel slope of 43.7 mV dec −1 were observed. Furthermore, when assembled as electrolyzers on both cathode and anode for stable water splitting, a low cell voltage of 1.514 V was needed for flower-like Mn 2 -CNN/NF to afford the current density of 10 mA cm −2 and distinguished durability for over 46 h was observed, which presented a wide range of possibilities for the development of earth-abundant and high efficient electrode pairs.
研究领域:
材料科学
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可再生能源
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电化学
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产品关联
DOI
高影响因子
Coatings
·
2023
·Vol. 13
·期 7
·1246
·
IF 3.4
Wenjuan Qi,Desheng Ding,Weijie Luo,Weiliang Jin,Qian Kou,Chuntao Ge,Saijun Xiao
The hardness and wear resistance of amorphous Al–Mn alloy coatings can be improved by incorporating ceramic particles into them to extend their application. In this paper, Al–Mn/WC composite coatings have been prepared with electrodeposition in stirred AlCl3–NaCl–KCl–MnCl2molten salts at 180 °C with the addition of WC particles. The effects of stirring speed (400–700 rpm) and cathode current density (15–75 mA/cm2) on the produced Al–Mn/WC composite coatings have been studied. At 600 rpm and 700 rpm, the Al–Mn/WC composite coatings exhibited the best uniform distribution of the embedded WC particles, with the tested microhardness value up to 650 HV0.1, compared with 530 HV0.1of the Al–Mn alloy. Moreover, under various cathode current densities, the best quality of the Al–Mn/WC composite coating was obtained at 55 mA/cm2, with a homogeneous distribution of WC particles and the highest microhardness value (670 HV0.1). It is expected that this method could be extended to be applied for the preparation of aluminum-based and magnesium-based ceramic composite coatings.Keywords:AlCl3–NaCl–KCl–MnCl2molten salts;electrodeposition;WC particles;Al–Mn/WC composite coating
研究领域:
材料科学
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表面工程
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DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
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2024
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IF 4
Jian-Wei Zhang,Ya Chen,Yong-Ya Zhang,Wei Wei
In this work, by utilizing an X-type tetracarboxylate ligand (1,2,4,5-tetrakis(4-carboxyphenyl)benzene, H 4 TCPB), a novel Mn-organic framework, namely, [(CH 3 CH 2 ) 2 NH 2 ] 2 [Mn(TCPB)(H 2 O) 2 ] ( SQNU-25 , SQNU = Shangqiu Normal University), was prepared under a DEF/HAc solm. Due to the structural advantage of SQNU-25 , the Ln 3+ ions (Eu 3+ and Gd 3+ ) have been successfully introduced into the framework by post-synthetic modification. The result of the energy levels of the H 4 TCPB ligand and Eu 3+ ion shows that the H 4 TCPB ligand as a chromophore can effectively sensitize Eu 3+ ions. Moreover, the Eu@SQNU-25 not only shows a typical Eu 3+ ion red emission but also exhibits good temperature sensing in the wide temperature range (80 to 300 K).
研究领域:
材料科学
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光学
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产品关联
DOI
高影响因子
Results in Physics
·
2019
·
IF 3.042
Yang Zhou,Xiaoyuan Liu,Ke Wang,Jing Li,Xinglai Zhang,Xin Jin,Xinyue Tang,Xiuhui Zhu,Ruishi Zhang,Xin Jiang,Baodan Liu
Series of “Hopcalite” catalysts for low-temperature CO oxidation are prepared through a facile ultra-sonic spray pyrolysis approach. It has been found that the spray pyrolysis temperature and Cu/Mn atomic ratio in initial precursors show significant impacts on the catalytic activity of Cu-Mn-O catalysts. The catalyst synthesized at 550 °C with Cu/Mn = 1/2 in precursor (Cu1Mn2-550) shows the highest catalytic activity towards CO oxidation (T 100 = 63 °C; E a = 17.04 KJ mol −1 ), owing to the formation of CuMn 2 O 4 phase with poor crystallinity. The synergistic effect of Cu and Mn species in spinel Cu-Mn-O phases attributes to the evaluated catalytic activity compared with those of pure oxides of copper or manganese towards CO oxidation. The results reveal that Cu1Mn2-550 not only provides more defects and vacancies to create more active sites, but also generates more highly active Cu (II) to promote CO oxidation. On the contrary, the decreasing amount of Cu (II) and the higher degree of crystallinity resulting from higher synthesis temperature lead to the deterioration of catalytic activity. Moreover, the phase transformation among the Cu x Mn 3-x O 4 spinels also shows significant effect on CO conversion rate. Finally, the formation mechanism of Cu-Mn-O catalysts and related CO oxidation process are discussed based on series of characterizations.
研究领域:
化学工程
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催化材料
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产品关联
DOI
高影响因子
Frontiers of Chemical Science and Engineering
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2024
·Vol. 18
·期 11
·1-10
·
IF 4.3
Liang Haoting,Zhao Qiao,Liu Shengkun,Wei Chongyang,Wang Yidan,Wang Yue,Huang Shouying,Ma Xinbin
The Fe-Mn bimetallic catalyst is a potential candidate for the conversion of CO 2 into value-added chemicals. The interaction between the two metals plays a significant role in determining the catalytic performance, however which remains controversial. In this study, we aim to investigate the impact of tuning the proximity of Fe-Mn bimetallic catalysts with similar nanoparticle size. And its effect on the physicochemical properties of the catalysts and corresponding performance were investigated. It was found that closer Fe-Mn proximity resulted in enhanced CO 2 hydrogenation activity and inhibited CH 4 formation. The physiochemical properties of prepared catalysts were characterized using X-ray diffraction, H 2 temperature programmed reduction, and X-ray photoelectron spectroscopy, revealing that a closer Fe-Mn distance promoted electron transfer from Mn to Fe, thereby facilitating Fe carburization. The adsorption behavior of CO 2 and the identification of reaction intermediates were analyzed using CO 2 -temperature programed desorption and in situ Fourier transform infrared spectroscopy, confirming the intimate Fe-Mn sites contributed to CO 2 adsorption and the formation of HCOO* species, ultimately leading to increased CO 2 conversion and hydrocarbon production. The discovery of a synergistic effect at the intimate Fe-Mn sites in this study provides valuable insights into the relationship between active sites and promoters.
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
APPLIED SURFACE SCIENCE
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2024
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IF 6.3
Longfei Ruan,Xueting Jiao,Xinyu Ge,Dapeng Cui,Zhengyi Sun,Xiao-chun Hang,Wei Shen,Zhengtao Deng
Metal ion doped semiconductor nanocrystals have attracted broad interest due to the doping ions could tailor their optical, electronic, transport, structure stability and spintronic properties. Herein, we report a novel ligand-mediated solvent-induced reprecipitation approach to synthesize stable and highly fluorescent thiol-passivated Mn-doped perovskite-related tetragonal CsPb 2 Cl 5 nanosheets (NSs). The rational tuning the chemical composition ( i.e. , Pb/Mn ratio) and controlling the crystal phase of the CsPb 2−x Mn x Cl 5 perovskite NSs have been achieved. Significantly, their crystal structure and photoluminescence properties are found to be well-reserved for over two months under ambient conditions. With the addition of Mn 2+ , the PL lifetime of CsPb 2 Cl 5 decreases, which further confirms the energy transfer of CsPb 2 Cl 5 to Mn 2+ , and energy transfer efficiency (η ET ) from CsPb 2 Cl 5 to Mn 2+ in CsPb 2−x Mn x Cl 5 NSs is as high as 54.9 %. Furthermore, benefited from the Mn 2+ doping, the antiferromagnetic fitting temperature of the NSs is −5 K, which indicates a strong antiferromagnetic coupling. This work suggests an expansive research prospect for application of metal ion doped perovskite-related materials in the field of optical, magnetic, and optoelectronics devices.
研究领域:
材料科学
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光学
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磁学
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半导体物理
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DOI
高影响因子
JOURNAL OF CHEMICAL SCIENCES
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2022
·Vol. 134
·期 2
·1-11
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IF 2.15
Yu Miao,Ji Shuai,Li Zhifang,Song Kun,Li Yueyu,Yang Jian,Yang Changlong
A simple ion-exchange method is used to prepare Mn and Co-supported TNU-9 denitration catalyst for NH 3 -SCR. The denitration activity and H 2 O/SO 2 resistance performance of the catalyst are systematically studied. The denitration activity test exhibits that the NO x removal rate of Mn-Co/TNU-9 is higher than that of Mn/TNU-9 and Co/TNU-9, the NO x removal rate is greater than 90% and the N 2 selectivity is greater than 99% in the range of 150 ~ 450 °C. It is because the redox cycle of Mn 4+ + Co 2+ ↔ Mn 3+ + Co 3+ improves the redox performance of the catalyst, which is conducive to the conduction of electrons, and then accelerates the oxidation of NO to NO 2 to produce a "fast SCR" reaction, and finally optimizes the overall SCR performance. Furthermore, the change is not significant for the catalytic activity over Mn-Co/TNU-9 in the presence of water. However, the sulfur resistance is poor at low temperatures due to the presence of ammonium bisulfate. It also has excellent catalytic stability. Therefore, supported TNU-9 catalysts will have a good development prospect in denitrification. Graphical abstract Mn-Co co-doped TNU-9 catalyst was successfully synthesized by simple ion exchange method and applied in the NH 3 -SCR. The results show that Mn-Co/TNU-9 catalyst has an excellent wide activity window in a wide temperature range of 150-450°C (NO x conversion over 90%), which is because Mn+Co 2+ ↔Mn+Co improves the redox performance and facilitates the electron transfer, which further accelerates the oxidation of NO into NO 2 that could result in the “Fast SCR” reaction. The synergistic effect between Mn and Co bimetallic can also improve activity. Moreover, Mn-Co/TNU-9 has very good catalytic stability.
研究领域:
环境科学
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催化化学
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DOI
高影响因子
CERAMICS INTERNATIONAL
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2019
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IF 3.45
Fan Feng,Yan Yan
The electric field in ferroelectric ceramics can induce notable deformations or strains based mainly on the electrostrictive effect if the driving field is sufficiently large (normally larger than the coercive field). Therefore, a large electrostrictive effect is highly desired to achieve a high strain output. In the present work, 0.5Ba(Zr 0.2 Ti 0.8 )O 3 -0.5(Ba 0.7 Ca 0.3 )TiO 3 (BCZT50) ferroelectric ceramics doped with different numbers of Mn ions were synthesized and their dielectric and ferroelectric properties were studied to comprehensively evaluate the electrostrictive effect in this system. The doping levels were set as 0.0025, 0.005, 0.01, and 0.02. It was found that Mn ions could lower the temperature corresponding to the maximum permittivity, T m , drastically and induce diffuse phase-transition behaviors simultaneously. Most importantly, a purely electrostrictive effect with a longitudinal electrostrictive coefficient, Q 33 , as large as 0.0466 m 4 /C 2 was observed between 22 and 80 °C. The Q 33 of Mn-doped BCZT50 ceramics is much higher than some representative lead-based and lead-free ferroelectric ceramics. In this paper, a potential lead-free ferroelectric system with a large electrostrictive effect, which has potential applications in electrostrictive actuators, is reported.
研究领域:
材料科学
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电陶瓷
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铁电材料
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执行器
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产品关联
DOI
高影响因子
ChemistrySelect
·
2024
·Vol. 9
·期 35
·e202402650
·
IF 1.9
Xinyi Wang,Zihan Cheng,Yuting Liu,Li Wang,Lili Chen
Graphical In the study, Mn-functionalized ZIF-67 (Mn@ZIF-67) hybrid material was synthesized using a post-synthesis modification method. Its oxidase-like catalytic activity effect enabled this material to directly oxidize colorless TMB into blue oxTMB without the presence of H 2 O 2 . This color change provided a means for the detection of Art and AA. The work also demonstrated the practical application of this method in analyzing real samples containing AA or Art. Artemisinin (Art) is the first-choice medicine for treating malaria. It also shows good therapeutic effects in antibacterial and antitumor treatment. Therefore, a simple and efficient method for detecting Art is of great significance. Mn-functionalized ZIF-67 (Mn@ZIF-67) hybrid materials were synthesized using a post-synthesis modification method. Due to the introduction of Mn 2+ , Mn@ZIF-67 possesses higher peroxidase/oxidase like dual-mimic enzymes activity than ZIF-67, which can catalyze Art and generate peroxyl radicals. Based on this fact, Mn@ZIF-67 was used to detect Art in the presence of TMB. A good linear relationship between absorption intensities at 652 nm and Art concentrations was obtained in the range of 0–22 μM with a detection limit of 200 nM. Ascorbic acid (AA), due to its reducibility, can inhibit peroxidase/oxidase mimetics activity of Mn@ZIF-67 and the blue Mn@ZIF-67-TMB solution fades gradually with the addition of AA. Mn@ZIF-67-TMB acting as a colorimetric sensor, AA can be sensitively detected ranging from 0–30 μM, and the detection limit is 50 nM. Coexisting substances don't interfere with the detection of Art or AA. This sensing platform provides a highly sensitive and selective colorimetric method for monitoring AA and Art in serum, thereby demonstrating remarkable practicality.
研究领域:
材料科学
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医学
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药物分析
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产品关联
DOI
高影响因子
CHEMOSPHERE
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2022
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IF 8.943
Nengwei Ma,Yifan Ru,Mili Weng,Lu Chen,Wenqing Chen,Qizhou Dai
In this study, the catalytic materials of MnO x /γ-Al 2 O 3 , CeO 2 /γ-Al 2 O 3 , and Mn x Ce 1-x O 2 /γ-Al 2 O 3 for catalytic ozonation were synthesized. The catalysts were used in heterogeneous catalytic ozonation of the wastewater containing ntrofurazone (NFZ). The effects of the catalytic ozonation operational factors were systematically evaluated in terms of ozone dosing, catalyst dosing, initial NFZ concentration, and pH. The results showed that the catalytic activity of the Mn x Ce 1-x O 2 /γ-Al 2 O 3 was higher than that of the MnO x /γ-Al 2 O 3 and CeO 2 /γ-Al 2 O 3 . The kinetics analysis revealed that bimetallic loading has a synergistic effect and the mechanism of this effect was investigated in the catalytic ozonation system. The catalysts were characterized by FESEM, EDS, XRD, XPS, IR , and BET. The characteristics of the catalysts revealed that Mn could alter the oxide species on the metal surface and interfere with the formation of CeO 2 crystals, which led to smaller grains, enhanced adsorption oxygen, and greater specific surface area. The Mn x Ce 1-x O 2 /γ-Al 2 O 3 crystals could form a solid solution, which helps higher catalytic activity . This study adds to the understanding of the synergistic mechanism of the loaded Ce–Mn oxide catalysts in the heterogeneous catalytic ozonation system and provides a feasible method for degrading pharmaceutical wastewater.
研究领域:
环境科学
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催化材料
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）