JOURNAL OF POWER SOURCES
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2024
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IF 8.1
Wei Liu,Xin Geng,Hailong Wang,Jing Chen,Chenyang Wang,Nian Zhang,Ahmed M. Hashem,Wei Chu,Xin He
Lithium (Li) - and manganese (Mn)-rich oxides ( x Li 2 MnO 3 ·(1− x ) Li TM O 2 , TM = Ni, Co, Mn, etc.) are one of the most promising cathode materials because of their high theorical capacity, which is contributed by the redox of both transition metal cations and oxygen anion. However, anionic redox leads to transition-metal migration and release of lattice oxygen, which further triggers voltage decay and capacity fade. Here, we report a dual-doping and multiphase co-existence strategy to tackle the structure degradation of Li- and Mn-rich materials and enhance electrochemical kinetics. La–Ti dual cations doping strength the TM -O bonds and improve cycling stability, and the inducement of LaMnO 3+ δ (LaMO) phase provides higher conductivity. As a result, the unique architecture presents a favourable rate performance, improved capacity retention, and suppressed voltage decay. After 200 cycles at 1C (250 mA g −1 ), the La–Ti dual cations doped Li-and Mn-rich material shows 24 % higher capacity retention and 52 % lower voltage decay compared to the non-doped material. This study demonstrates the potential of dual transition-metal ion doping combined with doping-induced perovskite phase to enhance the performance of Li- and Mn-rich materials.
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APPLIED CATALYSIS B-ENVIRONMENTAL
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2024
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IF 20.2
Bin Zhang,Shuangqing Xia,Zhenyi Wang,Wenqian Li,Boda Li,Haochen Zhang,Yanjun Xin,Kai Wu,Jun Ma,Xu He
Permanganate [Mn(VII)] needs to be activated to improve its reactivity towards refractory organic contaminants in practice. Herein, visible light (VL) and graphitic carbon nitride (g-C 3 N 4 ) were introduced to enhance the activation of Mn(VII) for the first time. Sulfamethoxazole (SMX) can be degraded effectively by VL/Mn(VII)/g-C 3 N 4 system in neutral and alkaline environments. Different from conventional Mn(VII) activation and photocatalytic processes, the performance of VL/Mn(VII)/g-C 3 N 4 system in various real water samples was superior than Milli-Q water. Mn(V) was found to be the dominant active species responsible for SMX degradation. Photo-induced electron (e cb – ) of g-C 3 N 4 under VL irradiation was proved to be the initiator of Mn(VII) activation. Density functional theory calculations revealed the strong affinity of g-C 3 N 4 for Mn(VII), which can resist the interference of water substrates on the Mn(VII) activation process by photo-induced e cb – . This work deepens the understanding of reactive manganese intermediates in the Mn(VII) activation system.
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APPLIED CATALYSIS A-GENERAL
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2025
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IF 4.8
Mengyao Luo,Longli Bo,Sining Huang,Haiguang Wang,Zhiyun Yang,Danjun Wang,Ying Yang,Zhe Li,Lu Wang
Adding polyethylene glycol (PEG) can lessen the shedding of coating and improve the dispersion of active particles for monolithic catalysts. In this study, a series of Cu-Mn-Ce-O x (P x )/TiO 2 (P x )/CH catalysts were prepared with different PEG molecular weights (P x , x = 200, 1000, and 2000) to explore the effect of P x addition on the structure and activity of the catalysts in microwave catalytic combustion of toluene. The research showed that P x addition (1 wt% dosage to titanium sol) to coating reduced the particle size of titanium sol and decreased the shedding rate of TiO 2 coating 0.9–0.93 %, and P x addition (3 wt% dosage to CH's water absorption) to active components further lessened the shedding rate of the catalysts 1.93–2.04 %. Under an initial toluene concentration of 1500 mg/m 3 and a gas hourly space velocity of 2260 h −1 , Cu-Mn-Ce-O x (P 1000 )/TiO 2 (P 1000 )/CH owned the highest catalytic activity and its complete removal temperature (T R100 ) and mineralization temperature (T M100 ) to toluene were 180℃ and 218℃, respectively, which were lower 33℃ and 16℃, 56℃ and 58℃ than Cu-Mn-Ce-O x /TiO 2 (P 1000 )/CH and Cu-Mn-Ce-O x /TiO 2 /CH catalysts separately, and its activity maintained steadily with toluene removal efficiencies of 99–91 % over 12 h. The improved activity is attributed to the uniform dispersion of active particles, larger specific surface area, and increased adsorbed oxygen, facilitated by pore-forming and steric-hindrance effects of P x . Electron transfer among Mn 4+ /Mn 3+ /Mn 2+ , Cu 2+ /Cu + , and Ce 4+ /Ce 3+ promoted the oxidation of toluene under microwave irradiation. Therefore, the research provides technological support for developing transition metals-based catalysts for industrial VOC waste gas treatment.
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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).
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SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Wenhao Gu,Jinxian Feng,Xingshuai Lv,Weng Fai Ip,Hui Pan
Photocatalytic CO 2 reduction has been considered as an efficient way for the carbon nuetrality. In this work, a series of (Cu, Mn) co-incorporated metal-orgnaic frameworks (MOFs) (NH 2 -MIL-125(Ti) (NML)) with different Cu 2+ /Ti 4+ and Mn 2+ /Ti 4+ molar ratios are systematically investigated to improve the efficiency for photocatalytic CO 2 reduction. The optimized sample (1 M−5C−−NML) shows a highest yield of HCOOH (116.74 μmol . g −1. h −1 ) (3.71 times higher than that of NML), and a superior apparent quantum efficiency (AQE) (6.74 % at 405 nm). The improved performance is attributed to the formed oxygen vacancy and intermediate energy level as introduced by the co-incorporation, which facilitate the charge separation and enhance the visible-light-harvesting of NML. It shows that the density of oxygen vacancies increases with the increasing amount of Cu, resulting in enhanced charge separation. However, the increasing amount of Mn leads to the short-range Mn-Mn interaction, the concentration quenching effect as well as the inhibited photocatalytic performance. This work shows that the co-incorporated MOFs can be used as an advanced photocatalyst.
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ACS Applied Energy Materials
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2025
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IF 5.5
Dongheng Zhao,Qian Ma,Ying Sun,Lingyu Li,Huayushuo Zhang,Bolong Li,Zhiqiang Liu,Xiaomei Jiang
Zero-dimensional organic zinc halides have garnered significant attention as efficient and eco-friendly photoluminescent materials. However, its luminance efficiency, which is typically attributed to self-trapped excitons formed within zinc halide tetrahedra, often encounters a serious thermal quenching problem. This issue significantly limits its application in the field of solid-state lighting. Intriguingly, the incorporation of tetra-coordinated Mn2+ ions into these organic zinc halides can effectively mitigate unnecessary electron interactions and nonradiative energy transfer between Mn–Mn, achieving significantly improved photoluminescence quantum yield (PLQY) in the alloyed materials. In this work, a series of zero-dimensional Mn2+-alloyed 4-benzylpiperidinum zinc chloride hybrids were designed and synthesized by a solvent evaporation method. It is noteworthy that the pure zinc chloride shows a negligible visible emission at 510 nm, whereas (C12H12N)2MnxZn1–xCl4 (x = 0.25, 0.5, 0.75, 1) emits visible light ranging from green to yellow at room temperature. Incorporating Mn has led to a remarkable enhancement in PLQY, increasing from a mere 4.02% in the organic zinc halide to an impressive 94.45% in the (C12H12N)2Mn0.75Zn0.25Cl4. The white LED was successfully fabricated by employing the optimal sample as a single-component yellow phosphor coated on 450 nm chip. The correlated color temperature was determined to be 4770 K with a color rendering index as high as 91. It was also demonstrated with good luminous stability under different working currents. This research provides a straightforward approach for developing eco-friendly, cost-effective, and high-performance single-component yellow phosphors for white LED applications.
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CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Shuangfu Gang,Yongxin Qian,Tianshun Xiong,You Li,Wang Li,Zheng Ma,Wenguang Zhang,Hui Long,Yingchao Wei,Xin Li,Qinghui Jiang,Yubo Luo,Junyou Yang
All-scale hierarchical defects induced by structural designing from unit cell to mesoscale play a significant role in oscillating and dissipating electromagnetic wave energy under external microwave radiation. To construct such all-scale hierarchical defects, hereby, high-entropy alloy nanoparticles coated by microscale carbon (HEA@C) with a core–shell structure were obtained by carbonizing Ni-Mn-Co-Cu-Al metal–organic. Thus, all-scale hierarchical defects were gained, including lattice distortion and nanotwins caused by the high entropy effect, vacancy and topological defects within carbon, and the heterojunction between high entropy nanoparticles and carbon. These all-scale hierarchical defects combined with the magnetic and conductive nature of HEA@C enable us to achieve a high electromagnetic wave absorption performance, with a reflection loss (RL min ) value of −52.36 dB and an effective absorption bandwidth (EAB) of 5.01 GHz. It implies that HEA@C should be an effective electromagnetic wave (EMW) absorber.
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FUEL
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2024
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IF 6.7
Liangyong Chen,Rui Mao
Developing robust catalytic oxygen carriers (COC) to make Chemical-looping Oxidation Coupling of Methane (CL-OCM) economical and practical remains a big challenge. This work modified the Mn-based catalysts for co-feed OCM and tried to adapt them into CL-OCM process. COCs were specially designed with high faction of Mn-oxides to improve oxygen storage, with supports (pelletized from SiO 2 , MgO and TiO 2 ) of stable and porous structure to improve cyclic stability and to tune lattice oxygen reactivity, and with Na + dopant to improve conversion and selectivity. Among the COCs, Mn20Na2Si and Mn20Si (20 wt% Mn 2 O 3 supported on SiO 2 with/without 2.0 wt% Na 2 CO 3 dopants) exhibited excellent methane coupling activity. The averaged CH 4 conversion, C 2 selectivity and yield of Mn20Na2Si upon multiple redox cycles were 21.4 %, 79.6 % and 17.03 %, respectively. It showed improvements in C 2 selectivity and yield by 187 % and 163 % compared to Mn20Si. This work tried to establish the relationships between CL-OCM performance and lattice oxygen behaviors, since COC transports lattice oxygen to promote methane coupling as it performs as a catalyst during CL-OCM reduction. It is found that high C 2 -selectivity and CH 4 conversion are benefited from the constant oxygen transporting rate. Na + dopant improved the concentration of surface lattice oxygens, tuned the spatial arrangement of metal oxides, and stabilized the surface lattice oxygen in cyclic reactions. Due to Na + -doping, carbon deposition on Mn20Na2Si was avoided, and catalyst deactivation as well. Finally, a mechanism was developed to reveal how lattice oxygen species and their releasing rates affected surface reaction network, CH 4 conversion, C 2 selectivity and cyclic stability.
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ACS ES&T Water
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2024
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IF 4.8
Jianwang Wu,Mei Lin,Zuliang Chen
Fenton oxidation is highly efficient for removing pollutants from wastewater. However, the low utilization efficiency of oxidants increases operating costs and limits their application in water treatment. To address these issues, this study designed a novel Fenton-like catalyst: zerovalent iron/amorphous manganese composites (ZVI-Mn). This catalyst can activate O2 in situ to generate H2O2 and simultaneously activate H2O2 to produce free radicals, achieving a 96.3% removal efficiency of enrofloxacin (ENR) from water. Radical quenching experiments showed that superoxide radicals (•O2–) (46%) play a dominant role in ENR removal, while hydroxyl radicals (•OH) (28.2%) and singlet oxygen (1O2) (25.8%) also participate. Liquid chromatography–mass spectrometry (LC–MS), density functional theory (DFT) calculations, and toxicity estimations demonstrated effective ENR degradation and significant toxicity reduction of the intermediates, primarily through decarboxylation and ring opening. Additionally, ZVI-Mn achieved a 90.1% removal efficiency of ENR in aquaculture wastewater. This study proposes a new Fenton oxidation technique based on the in situ generation of H2O2, providing a meaningful research basis for environmentally friendly water treatment technologies.
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ACS ES&T Water
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2025
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IF 4.3
Xinyue Zhang,Zhichao Yang,Hongchao Li,Bingcai Pan
Transition-metal oxide-mediated peroxide activation systems have been demonstrated to initiate selective degradation of pollutants, while the underlying mechanism remains unclear and sometimes controversial. In this study, we systematically explored the reactive species/pathways for pollutant degradation in the Mn oxide octahedron molecular sieve (OMS-2)-triggered peracetic acid (PAA) activation system. By separating PAA activation and pollutant oxidation processes using a sequential activation/oxidation system or galvanic oxidation system, we confirm that the OMS-2/PAA system follows the reactive metal species mechanism, where surface reactive Mn(IV) species, rather than Mn–PAA complexes, are primarily responsible for the nonradical oxidation of bisphenol A. OMS-2 shows varied peroxide-activating activities (i.e., catalase-like and peroxidase-like activities) toward different peroxides (i.e., H2O2, PAA, and persulfates), depending on the reactivity of surface reactive Mn(IV) species with those peroxides. In addition, the long-lived surface reactive Mn(IV) species exhibit excellent resistance to fluctuations in solution pH and interference from coexisting anions and natural organic matter. This study offers novel insights into the nonradical mechanism involved in Mn oxide-mediated peroxide activation processes.
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JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2024
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IF 4.1
Junxiao Shen,Yi Hao,Yangxi Yan,Zhimin Li,Pangpang Wang,Ri-ichi Murakami,Dongyan Zhang
Layered cathode materials for lithium-ion batteries have been extensively investigated; however, comparatively scant attention has been paid to Mn-rich layered cathode materials. Herein, LiNi 0.5 Mn 0.5 O 2 cathode materials are doped to investigate the effect of doping elements on the electrochemical properties of Mn-rich layered cathodes. XRD (X-ray diffraction), XPS (X-ray photoelectron spectroscopy), and SQUID (superconducting quantum interference device) results reveal that Mo doping affects the electrochemical properties of the cathode materials by changing the valence state of transition metal ions. Due to the Mo 6+ ions doping, a large proportion of Mn 3+ ions present in LiNi 0.5 Mn 0.5 O 2 were converted to Mn 4+ ions, which alleviated the Jahn-Teller effect and reduced the elongated Mn-O octahedra, thus increasing the Li layer spacing and facilitating Li + diffusion. Therefore, 1 % Mo-doped cathode exhibits a significantly improved Li-ion diffusion coefficient and superior rate performance with a specific discharge capacity of 103 mAh·g −1 at 5C. Meanwhile, the cathode materials significantly improve cycling performance due to the reduction in the amount of Mn 3+ . The current study provides guidelines for the modification of Mn-rich layered cathodes in the future.
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Journal of Environmental Chemical Engineering
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2024
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IF 7.4
Ying Huang,Juan Lei,Baobao Bai,Xiaoli Ren,Lijun Cheng,Yu Cao,Shuang Wang,Jinping Li
Traditional powder catalysts are not suitable for industrial applications due to low utilization of active phase and easy sintering. Therefore, monolithic catalyst MCCF with good stability and water-resistance was designed for the catalytic oxidation of toluene-acetone mixture, in which amorphous MnO x derived via pyrolysis of Mn-MOFs loaded on copper foam (CF) and different transition layers were employed between MnO x and CF to regulate Cu-Mn interaction. The combined action of amorphous MnO x and the Cu-Mn strong interaction enhanced the catalytic degradation of toluene-acetone mixture. The existence of amorphous MnO x and the impacts of Cu-Mn interaction on weakening Mn-O bonds and stimulating reactive oxygen species were verified by various characterizations. Furthermore, the reaction pathways of toluene and acetone on catalyst MCCF were revealed as well as their interactions within the mixture.
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