Frontiers in Energy Research
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2020
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IF 2.746
Zhou Weijun,Wang Anran,Huang Aixiang,Chen Minfeng,Tian Qinghua,Chen Jizhang,Xu Xinwu
With the advantages of intrinsic safety, low price, high output potential, and acceptable energy density, aqueous rechargeable Zn–MnO2 batteries are gradually emerging as promising energy storage devices in recent years. Unfortunately, the structural instability and poor electrical conductivity of manganese dioxides still hinder their further applications. To tackle these issues, we demonstrate a high-performance cathode material for Zn–MnO2 batteries by hybridizing lignin-derived porous carbon with δ-MnO2 (denoted as LPC/δ-MnO2). Benefiting from the high electrical conductivity of porous carbon, the LPC/δ-MnO2 cathode material can offer high discharge capacity of 332.3 mAh g–1 at 0.2 A g–1 and excellent high-rate capability (196.1 mAh g–1 at 5 A g–1). Meanwhile, the assembled Zn–MnO2 battery displays good long-term cycling stability (82% capacity retention after 1000 cycles). Such superior performances are attributed to the synergetic effect of nanostructured δ-MnO2 and porous carbon scaffold, which is in favor of rapid Zn2+ ion diffusion and large contribution ratio of pseudocapacitive Zn2+ ion intercalation. The results of this study show great prospects of hybridizing biomass-derived carbon framework with electrochemically active materials toward advanced energy storage materials.
研究领域:
材料科学
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能源存储技术
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
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IF 5.518
Bao Zhang,Yannan Zhang,Bowen Zhu,Jianguo Duan,Xue Li,Xiaoyuan Zeng,Zheng Lian,Rui Gong,Kai Zhou,Zhengwu Wang,Yifeng Gao,Peng Dong,Yingjie Zhang
Spinel LiMn 2 O 4 (LMO) positive material has the advantage of a robust structure with a three-dimensional network of channels for fast Li + conduction, which is one of the hot topics in the zero-cobalt electrodes field of new energy technology. Nonetheless, the spinel LiMn 2 O 4 has serious transition metal dissolution as well as phase/surface stability problems, resulting in unsatisfactory cycle performance which hinders large scale applications in the field of lithium-ion batteries. In this study, Sm 2 O 3 surface modified LiMn 2 O 4 positive material is obtained by a facile ultrasonic cavitation combined with sol-gel strategy. The structural and surface morphological are analyses by X-ray diffraction, X-ray photoelectron spectroscopy and high resolution transmission electron microscopy illuminate the formation of the Sm 2 O 3 -coated LiMn 2 O 4 . Electrochemical analysis revealed that the LMO particles coated by the 1 wt% Sm 2 O 3 is exhibited the best electrochemical performance among other coated and non-coated samples, with an initial capacity of 110.92 mAh g −1 and a capacity retention of 94.79% after 200 cycles. Furthermore, ICP analysis is showed that the manganese dissolution of the modified material in organic electrolyte is much lower than that of pristine sample. This work may provoke wide interests in surface modification areas and motivate the further improvement of the electrochemical performance for other commercialized spinel lithium ion batteries (LIBs).
研究领域:
材料科学
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能源技术
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表面改性
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产品关联
DOI
高影响因子
Molecular Catalysis
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2022
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IF 5.089
Mingxun Han,Fanji Liu,Xiangxiang Li,Xiqing Zhang,Yiren Lu,Yanjun Lin,Lihong Zhang
A series of manganese-based catalysts supported on γ-Al 2 O 3 with low loading amount of manganese from 0.5% to 2.0% were prepared by incipient impregnating method. All catalysts were tested on non-oxidative dehydrogenation of isobutane at 600 °C. In order to explore physicochemical properties of all catalysts, various characterizations including XRD, H 2 -TPR, XPS, UV-vis, NH 3 -TPD and TG were carried out on manganese-based catalysts. The experimental results indicated that MnO x species were highly dispersed on γ-Al 2 O 3 support, and both Mn 2+ and Mn 3+ ions are main active species for isobutane dehydrogenation. The reduced catalyst 1.5%Mn/ γ -Al 2 O 3 exhibited the most optimal dehydrogenation performance among all catalysts, reaching at isobutane conversion of 36% and isobutene selectivity of 79%. The main reasons for the excellent activity and selectivity of 1.5%Mn/ γ -Al 2 O 3 were related to the high proportion of low valence manganese ions including Mn 2+ and Mn 3+ as well as the high concentration of medium strong acid sites and weak strong acid strength.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
BIOMATERIALS
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2022
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IF 15.304
Haiyan Pan,Quan Zou,Tingting Wang,Dong Li,Shao-Kai Sun
Diverse oxygen generation strategies have been developed to overcome hypoxia in tumors for enhancing the therapeutic efficacy, but inevitably suffering from tedious synthesis process of oxygen generators in vitro before in vivo administration. Herein, we show direct injection of commercially and clinically used KMnO 4 into solid tumors enables in situ formation of MnO 2 as an oxygen depot for cascade oxidation damage and enhanced photodynamic therapy. KMnO 4 can damage tumor tissues by oxidation and generate MnO 2 , and subsequent intravenous injection of Ce6 allows MnO 2 -triggered hypoxia-modulated photodynamic therapy of tumors. Excellent cascade tumor suppression effect is realized both in vitro and in vivo based on the KMnO 4 –Ce6 system without the need of synthesis. The proposed strategy lays down a novel way with unprecedented superiors of no need of synthesis process and ultra-facile administration procedure for tumor hypoxia-modulated cascade therapy.
研究领域:
肿瘤学
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生物医学工程
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药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
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2023
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IF 9.5
Linghong Zhang,Yi Liao,Meng Ye,Wenqin Cai,Meng Xiao,Changyan Hu,Benhe Zhong,Fang Wan,Xiaodong Guo
Large quantities of spent lithium-ion batteries (LIBs) will inevitably be generated in the near future because of their wide application in many fields. It will cause not only resource waste but also environmental pollution if these spent batteries are not properly handled. Until now, the recycling of spent lithium manganate batteries has centered on high-valuable elements such as lithium; however, manganese element and current collector Al foil have not yet attracted wide attention. In this work, aluminum-doped manganese dioxide was synthesized by overall recycling cathode active materials and current collector Al foil from a spent lithium manganate battery. Employing such aluminum-doped manganese dioxide as the cathode material of aqueous Zn batteries, it displays better electrochemical performance than manganese dioxide prepared by only recycling the cathode active materials. The overall recycling not only simplifies the recycling process but also realizes high-value recycling of spent lithium manganate batteries. We offer new tactics for overall recycling of cathodes from spent LIBs and designing high-performance manganese dioxide cathodes for aqueous Zn batteries.
研究领域:
材料科学
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环境科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
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2025
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IF 7.2
Qin Guo,Ying Cao,Jin Jiang,Juan Li
The permanganate/sulfite (Mn(VII)/sulfite) process has shown promise for degrading recalcitrant organic micropollutants, yet current methods to differentiate the roles of intermediate manganese species (IMS) and sulfate radicals (SO₄ •- ) show limitations. In this study, atrazine (ATZ) - a widely detected and oxidation-resistant herbicide - was used as a probe compound to investigate the reactivity of IMS and SO₄ •- generated in the Mn(VII)/sulfite system. ATZ exhibited negligible degradation by Mn(VII) alone but underwent rapid transformation within seconds in the presence of sulfite, with degradation efficiency increasing at lower pH and optimal [Mn(VII)]/[sulfite] ratios. Using stopped-flow spectrophotometry, pseudo-first-order kinetics were confirmed. Six major transformation products were identified, among which atrazine amide (CDIT) and desethyl-atrazine (DEA) were predominant. The molar ratio of CDIT to DEA ([CDIT]/[DEA]) was evaluated as a mechanistic indicator. A consistent ratio of ~4.8 at low sulfite levels indicated Mn(V)-dominated oxidation, while lower ratios at higher sulfite concentrations reflected increasing contributions from Mn(III) and SO 4 •− . This trend was supported across pH 3, 5, and 7. Water matrix components such as natural organic matter and nitrite were found to inhibit ATZ degradation, likely due to their scavenging of reactive species. This study establishes the [CDIT]/[DEA] ratio as a novel mechanistic indicator in manganese-activated oxidation and highlights the Mn(VII)/sulfite process as an effective strategy for degrading recalcitrant micropollutants in water treatment.
研究领域:
环境化学
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水处理技术
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氧化还原过程
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污染物降解机制
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自由基化学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Wentao Li,Qian Zhang,Zuohua Liu,Changyuan Tao,Guocan Zheng,Nanxiong Chen,Dong Wang,Hufei Chen
The long-term accumulation of manganese sulfate residues can lead to the release of soluble manganese ions, thereby contaminating the surrounding environment. Although numerous methods exist to address the issue of soluble manganese ions, current harmless treatment approaches fail to consider the subsequent utilization of manganese slag. This study aims to control the magnetic properties of processed residues by adjusting the addition of barium hydroxide and the reaction duration. Our results reveal that the harmless treatment of manganese sulfate slag is achievable with various amounts of barium hydroxide, and the magnetic properties of the reconstructed slag increase with the increased barium hydroxide dosage. Magnetic separation is employed to separate the magnetic components from the reconstructed slag, and the distribution state of these magnetic substance is modulated by altering the particle size and reagent addition. Under optimal conditions, this study finds that the grade of iron was 24.17 %, the grade of manganese was 8.08 %, and the recovery could reach 79 % for iron and 70 % for manganese. Finally, the fining slag obtained by magnetic separation was utilized as an additive in the preparation of ferrites, reducing the minimum reflection loss of the ferrites to −16.18 dB, signifying up to 90 % electromagnetic wave attenuation. These findings indicate that the fining slags holds great potential as a dopant for ferrites, offering a viable pathway for the resourceful and environmentally friendly treatment of manganese sulfate residues.
研究领域:
环境科学
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材料科学
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冶金工程
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Qiao Wang,Mengyao Xiao,Ken Fang,Xing Du,Zhihong Wang,Xinglin Lu
Manganese is widely distributed in the natural environment, and its presence in drinking water poses a risk to human health. In this study, an integrated pre-deposited powdered activated carbon (PAC) and manganese oxide (MnO x ) bio-functional layer of inorganic origin was coupled with gravity-driven ceramic membrane (GDCM) reactor. The study aims to investigate the effects of the membrane pore size and functional layer integrity on the Mn 2+ removal and flux. The results reveal that the average Mn 2+ removal efficiency of the large pore size membranes (300 kDa and 0.45 μm) was lower (75 % – 78 %) compared to those with smaller pores (15 kDa and 50 kDa) (87 % – 88 %) during long-term operation. Such differences are attributed to a period of manganese leakage before the PAC-MnO x matured in large-pore membrane units and a longer residence time in small-pore membranes. The functional layer leaded to reversible fouling, which was more prominent in membranes with larger pores (contributing to 93 % of total resistance) than those with smaller ones (ranging from 51.7 % to 61.9 %). Although the damaged functional layer resulted in occasional high Mn 2+ concentrations in the effluent, it did not significantly impact long-term flux development. Optical coherence tomography (OCT), in conjunction with COMSOL analysis, non-destructively evaluate biofilm formation process and indicate a homogeneous flow field and mass transfer in the “dual layers” (active film layer and ceramic membrane layer) of the GDCM. The presence of manganese-oxidizing bacteria ( Hyphomicrobium, Reyranella, and Pseudomonas ) in the GDCM reactor was verified using confocal laser scanning microscopy (CLSM) and high-throughput sequencing. Additional material characterization revealed that a portion of the PAC-MnO x exhibited characteristics of birnessite, with autocatalytic oxidation of Mn 2+ , and that Mn (III) and Mn (IV) were the primary species in MnO x , which exhibited excellent catalytic oxidation and adsorption capabilities for Mn (II), respectively. Overall, the developed PAC-MnO x GDCM system shows great promise in efficiently removing manganese and producing water of desired quality, thereby holding potential in applications across several sectors of advanced water treatment processes.
研究领域:
环境工程
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水处理技术
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产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2023
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IF 8.4
Jing Wang,Youlong Xu,Yao Niu,Yali Liu,Xianghua Yao
A critical challenge in the commercialization of spinel lithium manganate materials is the bulk structure damage and capacity degradation due to manganese dissolution during battery operation. Hence, Li3PO4 with good ionic conductivity was homogeneously deposited on the surface of spinel lithium manganate by the sol–gel method, aiming to improve the stability and cycling of the spinel structure by an epitaxial layer. The structural and electrochemical characterizations reveal that the presence of the Li3PO4 epitaxial coating prevents the direct contact of the cathode surface and electrolyte, thus enhancing the stability of the structure and reducing the extent of manganese dissolution. Further studies have shown that the contribution of the Li3PO4 layer promotes the diffusion coefficient of lithium ions, which increases from 7.89 × 10–12 to 4.43 × 10–11 cm2 s–1. Meanwhile, the Li3PO4 coating regulates the concentration of oxygen vacancies on the surface of the spinel, effectively reducing the transfer resistance and increasing the electronic conductivity to 3.50 × 10–5 cm–1. Specifically, the discharge specific capacity of the 1.0 wt % Li3PO4-modified electrode is still 115.4 mAh g–1 after 300 cycles, with the capacity retention increased to 90.8%. Even at a high rate of 10C, it still demonstrates excellent rate capability, with the discharge specific capacity more elevated than that of the unmodified material at about 40 mAh g–1. This strategy can simultaneously solve the interfacial instability and bulk structure degradation, thus improving the electrochemical performance of lithium manganate materials.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2024
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IF 10.8
Yaohua Wu,Huazhe Wang,Juanshan Du,Yi Hu,Qinglian Wu,Wanqian Guo,Wonyong Choi
This study demonstrates that the oxidation of bromide by birnessite (δ-MnO2) results in the concurrent production of soluble manganese (Mn(II)) and reactive bromine (RBr) species in frozen solutions, a process not observed in aqueous solutions. This enhanced oxidation in ice is attributed to the concentration of protons, birnessite, or bromide in the ice grain boundary region. Furthermore, different types of commercial manganese oxides can also oxidize bromide to RBr and release Mn(II) in ice. The presence of fulvic acid (FA) further increases the simultaneous production of RBr and Mn(II) in ice, accompanying the formation of organobromine compounds (OBCs). In frozen δ-MnO2/Br–/FA system, a significant increase in OBCs, mainly highly unsaturated and phenolic compounds, was detected using Fourier transform ion cyclotron resonance mass spectrometry. A marked contrast was observed in the number of OBCs formed in frozen solutions (853 and 415 OBCs at initial pH 3.0 and 5.8, respectively) compared to their aqueous counterparts (11 and 23 OBCs). These findings introduce a new pathway for the formation of RBr, Mn(II), and OBCs in ice, highlighting the need for further research on the environmental fate of bromide and manganese.
研究领域:
环境科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
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2024
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IF 6.3
Yao Niu,Jing Wang,Peifeng Wang,Haiyang Xing,Kai Zhang,Youlong Xu
The surface anisotropy of spinel LiMn 2 O 4 crystals exerts a profound influence on the electrochemical performance of the material. The truncated octahedral structure consists of various crystal facets such as {1 1 0}and {1 1 1}. Among them, {1 1 0} facets are conducive for the lithium-ion diffusion, although it will worsen manganese dissolution. In contrast, densely arranged {1 1 1} surfaces can reduce manganese dissolving but hinder lithium-ion diffusion. To balance ion diffusion and manganese dissolution, the ratio of {1 1 0} and {1 1 1} planes is regulated using the Mg/Al/Ti multi-doping approach. The percentage of {1 1 0} facets exposed is effectively increased by Mg/Al co-doping, and the exposure of the truncated facets improves the lithium-ion diffusion coefficient from 7.17 × 10 -12 to 1.02 × 10 -11 cm 2 s −1 , while also increasing the manganese dissolution from 1.15 % to 1.67 %. The addition of Ti reduces the proportion of truncated surfaces and mitigates manganese dissolution (1.39 %). The lithium-ion diffusion coefficient is maintained at 9.17 × 10 -12 cm 2 s −1 , and Mg/Al/Ti co-doping maintained a discharge specific capacity of 94.0 mAh/g after 500 cycles with a degradation rate of 0.062 % per cycle. Surface optimization and reconfiguration of regulated electrode materials can provide new possibilities for the development of lithium-ion batteries.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
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2022
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IF 9.794
Mingjun Nan,Lin Qiao,Yuqin Liu,Huamin Zhang,Xiangkun Ma
Manganese-based flow battery is desirable for electrochemical energy storage owing to its low cost, high safety, and high energy density . However, long-term stability is a major challenge for its application due to the generation of uncontrolled MnO 2 . To improve the cycle life, we propose a charge-induced MnO 2 -based slurry flow battery (CMSFB) for the first time, where nano-sized MnO 2 is used as redox-active material. The reaction mechanism of MnO 2 is discussed in detail. Benefiting from the electrostatic interaction , MnO 2 particles are homogeneously dispersed in the electrolyte during the charge process and contact sufficiently with the reaction sites of the electrode during the discharge process. As a result, the novel CMSFB exhibits coulombic efficiency of over 99% and energy efficiency of over 85% at a current density of 40 mA cm −2 and can run stably over 1000 cycles without capacity decay. This work opens new opportunities for the development of manganese-based flow batteries and slurry flow batteries.
研究领域:
能源存储
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材料科学
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电化学
✓ 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）