Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Xiao Yu,Banghong Deng,Lixia Yang,Moliang Zou,Zhenglin Chen,Yixuan Fan,Zhihui Wei,Kai Chen,Mingxia Lu,Tiantian Ying,Jie Zhang,Weili Dai
Mn 2 O 3 is a conventional catalyst that is applied in photothermal catalytic oxidation of toluene while regular anions like SO 4 2- , Cl - , and NO 3 - from different Mn precursors are left in Mn 2 O 3 . When applied in toluene degradation, the declining activity of Mn 2 O 3 is always observable because the residual anions block the Mn 4+ /Mn 3+ active sites, shield the oxygen vacancies, and cube the production of active oxygen species (O 2 - , O - ). Herein, it is found that the residual SO 4 2- , Cl - , and NO 3 - make Mn 2 O 3 incapacitated in deeply oxidizing the intermediates and cutting off the reaction process, and their influence ranks in the order of SO 4 2- >Cl - >NO 3 - . Compared with pristine Mn 2 O 3 , the drops in CO 2 conversion efficiency account for 11 %, 60 %, and 73 %, respectively. Nevertheless, rinsing with water is an effective method to remove the residual anions, and the more the rinsing, the better the toluene mineralization degree. This work provides a profound cognition of the deactivation mechanism of SO 4 2- , Cl - , and NO 3 - and points out an effective way to abate their negative effect for the first time.
研究领域:
环境科学
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催化材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Jiayong Ni,Tian Lan,Pu Liu,Yong Lu
The fluidized-bed reactor with excellent heat and mass transfer features has great appeal for application in the oxidative coupling of methane (FB-OCM), whereas qualified fluid catalysts represent a grand challenge. Herein, we report a high-performance Mn 2 O 3 -Na 2 WO 4 /TiO 2 fluid catalyst (5.4 wt% Mn 2 O 3 and 2 wt% Na 2 WO 4 ), which was obtained by the incipient-wetness impregnation method and examined in the OCM reaction in an electric-heating quartz fluidized-bed reactor (i.d., 2 cm). The standard normalization method on the basis of carbon atom was used for calculating the CH 4 conversion and C 2- C 3 selectivity. This catalyst achieves 35.5 % CH 4 conversion, 66 % C 2 -C 3 selectivity and particularly 15.1 % single-pass yield of C 2 H 4 for a feed of CH 4 /O 2 /H 2 O=3/1/1 with a catalyst dosage of 20 mL at 700 °C and a total GHSV of 7200 h −1 . Such catalyst is stable for at least 50 h without signs of deactivation and agglomeration/defluidization. The catalyst particle size is crucial for the FB-OCM reaction with respect to the reaction light-off and catalyst fluidization. The catalyst with preferable particle size of 450–600 μm can not only trigger the OCM reaction at a relatively low temperature of 630 °C but also warrant active bubbling fluidization. Furthermore, thanks to the low amount of Na 2 WO 4 and interpenetrating structure of TiO 2 -nanorod, such catalyst achieves good anti-aggregation and robust mechanical strength (with a low attrition index of 1.9 %). The effects of water-adding amount in feedstock and catalyst particle size distribution on the hydrodynamics behaviour were investigated in a laboratory-scale fluidized-bed OCM reactor by using numerical simulation method.
研究领域:
化学工程
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
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2024
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IF 4.7
Tao Peng,Chuanqiang Li,Liyun Song,Cui Liu,Feng Wang,Qianqian Chai,Shimin Li,Qiang Guo,Xuxu Zheng
Three Mn 2 O 3 with different morphologies and particle sizes were synthesized using MnBDC as precursor. Interestingly, the morphology and size of MnBDC can be easily regulated by changing the reaction solvents slightly. The Mn 2 O 3 -L catalyst with large layers and small crystal size exhibited the best catalytic activity for complete oxidation of propane, with T 50 of 266℃ and T90 of 311℃ at the WHSV of 120 L g −1 h −1 . The multi-layered structure and small crystal size of Mn 2 O 3 -L allowed it to possess a high surface area and more interfacial oxygen defects that facilitated oxygen mobility, improving the catalytic activity. It seems that the large precursor size of MnBDC-L slowed down the decomposition rate of ligands, promoting the formation of large layered structure and small crystal size of Mn 2 O 3 -L. This study offers a simple strategy to control the structure and crystal size of Mn 2 O 3 catalysts.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED ELECTROCHEMISTRY
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2016
·Vol. 46
·期 10
·1059-1065
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IF 2.223
Lu Haiting,Zhang Yan,Liu Peifang
Abstract Mn 2 O 3 microcubes with three-dimensional (3D) micromesoporous network structure were synthesized by thermal decomposition of the as-prepared MnCO 3 precursor. The structure, morphology, and textural property of the as-synthesized Mn 2 O 3 microcubes were characterized. The electrochemical property and electrochemical sensing performance toward nitrite detection were investigated. Owing to the unique 3D micromesoporous network structure, the Mn 2 O 3 microcubes could provide electrochemical sensing of nitrite with high sensitivity, selectivity, and reliability. Graphical Abstract
研究领域:
材料科学
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电化学
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分析化学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Electrochemical Science
·
2024
·
IF 1.3
Ying Geng,Chun-yong Zhang,Lin Zhu,Hao-yu Wang,Ji-rong Bai,Jing-jing Huang,Zhen-long Zhao
s Polymer catalyst electrodes have good electrical conductivity, high mechanical strength and other characteristics, which have good prospects in the future market of green and low carbon. In this paper, the electrode of PEDOT polymer catalyst is studied, and the electrochemical performance of the electrode is improved by doping different metals. This study describes the design of PEDOT-Co 3 O 4 @Mn 3 O 4 /Mn 2 O 3 catalysts by simple solvothermal synthesis. As a catalyst in the hydrogen evolution reaction (HER), the overpotential of the same polarization curve is much smaller than that of PEDOT, with a Tafel slope of 118.21 mV dec ‐1 , by electrochemical and characterization analysis. In the test of the supercapacitor performance, it has a large specific capacitance of 1298.5 Fg -1 and a small electrical impedance (0.21 Ω). After 2000 cycles of CV test, the capacitance remains 87.76 %, and the curve shape is stable, which proves that it has good electrochemical performance. Our results confirm the materials have great application prospects in HER and capacitors.
研究领域:
材料科学
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电化学
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能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2021
·
IF 7.92
Weidong Sun,Ya Gao,Guofeng Zhao,Jiaqi Si,Ye Liu,Yong Lu
Ethylene in principle can be obtained via oxidative coupling of methane (OCM), but it is urgently calling for a low-temperature active and selective catalyst. To accomplish this goal, the Ce x Zr 1-x O 2 solid solutions with varied Ce/Zr molar ratio were modified with Mn 2 O 3 -Na 2 WO 4 to fabricate OCM catalysts. The effects of Ce/Zr ratio and Mn 2 O 3 -Na 2 WO 4 doping were investigated on the catalyst reactivity for the OCM, showing that the reaction light-off temperature, activity and selectivity are subject to the Ce/Zr molar ratio and Mn 2 O 3 -Na 2 WO 4 doping. The promising catalyst with Ce/Zr molar ratio of 0.15/0.85 achieves 25% CH 4 conversion with 67% selectivity to C 2 -C 3 at 660 °C and is stable for at least 100 h. The catalysts were systematically studied by CH 4 -TPSR, O 2 -TPO/-TPD, CH 4 -pulse, in-situ FT-IR, EPR and XPS, showing that the Mn 2 O 3 -Na 2 WO 4 doped Ce 0.15 Zr 0.85 O 2 can generate more O 2 – species thereby leading to a markedly improved activity and selectivity at much lowered reaction temperature.
研究领域:
催化化学
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材料科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Aimal Khan,Xianjie Feng,Chuankun Yin,Habib Ullah,Asif Ali Tahir,Bowen Li,Weiming Wang,Xiaoxia Li,Aihua Xu
Less-toxic, cost-effective, stable, and highly efficient catalysts for sodium sulfite (S(IV)) activation are required to degrade organic pollutants from wastewater. Herein, we report the facile thermal synthesis of Mn 2 O 3 @Mn 5 O 8 that activates S(IV) more efficiently than other Mn and transition-metal oxides. Mn 2 O 3 @Mn 5 O 8 exhibits good performance and long-term stability for eliminating various contaminants from aqueous media, including phenol, bisphenol A, nitrobenzene, 2,4-dichlorophenol, and acetaminophen. Its high performance is attributed to its multivalency, unique architecture, surface hydroxyl groups (–OH), and high surface area. X-ray diffractometry and high-resolution transmission electron microscopy revealed that Mn 2 O 3 @Mn 5 O 8 comprises well-combined cubic Mn 2 O 3 and monoclinic Mn 5 O 8 crystalline structures, whereas electron paramagnetic resonance spectroscopy and scavenging tests showed that SO 5 •− , SO 4 •− , and •OH radicals are generated during S(IV) activation, with SO 3 •− as a precursor. The mixed-valence state provides effective and favorable electron transfer via Mn redox cycling (Mn(II) ↔ Mn(III) ↔ Mn(IV)), improving the S(IV) activation performance and catalytic activity. Mn 2 O 3 @Mn 5 O 8 /S(IV) system shows stable performance in the 3.0–7.0 pH range. Density functional theory calculations confirmed the higher catalytic activity as indicated by high –OH adsorption energy and significant inter-charge transformation. This study provides new insights and strategies for the activation of S(IV) using less-toxic metal oxides as catalysts and broadens the scope of heterogeneous Mn-based catalysts and S(IV) chemistry in real-world applications, particularly for the treatment of wastewater.
研究领域:
环境科学
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材料科学
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化学
✓ 已验证
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2016
·Vol. 22
·期 29
·9909-9913
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IF 5.771
Wenhai Wang,Jing Geng,Long Kuai,Min Li,Baoyou Geng
Graphical Low cost, high value : An Mn 2 O 3 catalyst with porous structure exhibits comparably activity to commercial Pt/C and notably higher activity than other Mn-based oxides, such as Mn 3 O 4 and MnO 2 . In light of the low cost and high earth abundance of Mn, the highly active Mn 2 O 3 is a promising candidate to be used as a cathode material in metal–air batteries and alkaline fuel cells. Preparing nonprecious metal catalysts with high activity in the oxygen reduction reaction (ORR) can promote the development of energy conversion devices. Support-free porous Mn 2 O 3 was synthesized by a facile aerosol-spray-assisted approach (ASAA) and subsequent thermal treatment, and exhibited ORR activity that is comparable to commercial Pt/C The catalyst also exhibits notably higher activity than other Mn-based oxides, such as Mn 3 O 4 and MnO 2 . The rotating ring disk electrode (RRDE) study indicates a typical 4-electron ORR pathway on Mn 2 O 3 . Furthermore, the porous Mn 2 O 3 demonstrates considerable stability and a good methanol tolerance in alkaline media. In light of the low cost and high earth abundance of Mn, the highly active Mn 2 O 3 is a promising candidate to be used as a cathode material in metal–air batteries and alkaline fuel cells.
研究领域:
材料科学
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电化学
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能源转换技术
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2018
·
IF 3.525
Pengwei Wang,Xin Zhang,Guofeng Zhao,Ye Liu,Yong Lu
Mn 2 O 3 -Na 2 WO 4 /SiO 2 is considered as the most promising catalyst for the oxidative coupling of methane (OCM) process; however, it only has a better catalytic performance over 800 °C. To improve its low-temperature performance, an attempt has been made to modify the Mn 2 O 3 -Na 2 WO 4 /SiO 2 catalyst using TiO 2 , MgO, Ga 2 O 3 , and ZrO 2 . Among the synthesized catalysts, the TiO 2 -modified Mn 2 O 3 -Na 2 WO 4 /SiO 2 catalyst shows markedly improved low-temperature OCM performance, achieving a high CH 4 conversion of ~23% and a good C 2 -C 3 selectivity of ~73% at 700 °C (the catalyst bed temperature), along with promising stability for at least 300 h without signs of deactivation. In comparison with the unmodified Mn 2 O 3 -Na 2 WO 4 /SiO 2 catalyst, the TiO 2 modification results in significant improvement in the low-temperature activity/selectivity, whereas the MgO modification has almost no impact and the Ga 2 O 3 and ZrO 2 modifications have a negative effect. The X-ray diffraction (XRD) and Raman results reveal that the formation of a MnTiO 3 phase and a MnTiO 3 -dominated catalyst surface is crucial for the improvement of the low-temperature activity/selectivity in the OCM process.
研究领域:
化学工程
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催化科学
✓ 已验证
DOI
高影响因子
Journal of Energy Storage
·
2025
·
IF 9.8
Mengke Wu,Lianchun Duan,Jiongchao Li,Jinya Sun,Yean Li,Jingying Hou,Yishun Xie,Xin Fan
The development of cathode materials with both high structural stability and superior specific capacity is crucial for advancing aqueous zinc-ion batteries (AZIBs). Manganese trioxide (Mn 2 O 3 ) has shown promise as a cathode material; however, its practical application is hindered by poor structural integrity and severe Mn dissolution during cycling, resulting in subpar electrochemical performance. To address these challenges, a fluorine (F) doping strategy was employed to enhance the stability of Mn 2 O 3 . F-doped Mn 2 O 3 (FMO) was synthesized via a hydrothermal method followed by high-temperature calcination. The effects of F-doping concentration on the material's structure and electrochemical behavior were systematically studied. The results reveal that F − partially substitutes lattice O 2− , increasing bond energy and reinforcing the [MnO 6 ] framework. This modification effectively reduces electrochemical polarization, enhances reaction kinetics, and improves charge/discharge reversibility. As a result, the Zn//FMO battery delivers an excellent specific capacity of 485.9 mAh g −1 at 0.1 A g −1 and maintains 125.9 mAh g −1 after 1000 cycles at 1.0 A g −1 . The findings demonstrate that F-doping is an effective strategy to overcome the intrinsic limitations of Mn 2 O 3 , offering a promising route toward high-performance AZIB cathodes.
研究领域:
材料科学
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电化学
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能源存储
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无机化学
·
纳米材料
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Yuwei Xue,Lihua Liu,Ting Zhang,Ziqi Zhu,Mingjun Xu,Qian Zhang,Junming Hong
There has been growing attention in the combination of metal oxide nanoparticles with metal-organic frameworks (MOFs) for the synergistically intensified catalytic activity . Herein, functional Fe-MOF@Mn 2 O 3 composites were synthesized to activate peroxymonosulfate (PMS) for 4-Cholophenol (4-CP) degradation via a hydrothermal and calcination method. Under the reaction parameters of 2 mM PMS, 0.2 g/L catalyst dosage, and pH 7.0, 91.4% of 4-CP (10 mg/L) could effectively be degraded within 60 min (2.2-fold increase in reaction rate constant compared with pure Mn 2 O 3 ). The excellent degradation performance of Fe-MOF@Mn 2 O 3 /PMS system was attributed to the surface hydroxyl and synergistic effect between iron and manganese. Quenching reaction and EPR analysis revealed both sulfate (•SO 4 - ) and hydroxyl radicals (•OH) were responsible for 4-CP degradation. The Fe-MOF@Mn 2 O 3 composite exhibited intensive catalytic capability as well as electron transfer efficiency according to the electrochemical measurements. Meanwhile, the possible degradation pathways were proposed by analyzing intermediates via LC-MS detection. The results indicates that the Fe-MOF@Mn 2 O 3 /PMS system is effective and adaptable for the treatment of 4-CP in different water conditions.
研究领域:
环境科学
·
催化材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Tian Lan,Weidong Sun,Xuerong Shi,Yong Lu
Intrinsic safety chemical looping-oxidative coupling of methane (CL-OCM) is an attractive method for direct conversion of methane to ethylene, but well-qualified oxygen carrier catalyst still remains challenging. Herein, we report a promising Na 2 WO 4 -doped Mn 2 O 3 -TiO 2 catalyst toward high-efficiency CL-OCM process. The standout Na 2 WO 4 /2Mn1Ti (Mn 2 O 3 /TiO 2 weight ratio of 2/1) catalyst, with good cycling performance, achieves a high space time yield of 27.8 (or 22.9) g C2-C3 kg cat −1 h −1 with 19.5 % (or 15.7 %) CH 4 conversion and 80 % (or 82.7 %) C 2 -C 3 selectivity at 740 (or 720) o C and a low catalyst/CH 4 weight ratio of 13.5. The TiO 2 substantially lowers the CL-OCM reaction temperature, due to the establishment of a low-temperature light-off “Mn 2 O 3 + TiO 2 ↔ MnTiO 3 ” redox cycle with CH 4 /O 2 . The enabling role of Na 2 WO 4 in modulating the reaction of Mn 2 O 3 with CH 4 into OCM instead of combustion is theoretically unveiled, which in nature benefits the *CH 3 transfer and spontaneous desorption to form ∙CH 3 radicals.
研究领域:
化学工程
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催化科学
✓ 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）