ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Xiaoyang Chen,Jian Chen,Yijie Liu,Yang Liu,Yun Gao,Siwei Fan,Xiangxi He,Xiaohao Liu,Chao Shen,Yong Jiang,Li Li,Yun Qiao,Shulei Chou
Metal–CO2 batteries, especially Li–CO2 and Na–CO2 batteries, are regarded as ideal new-generation energy storage systems owing to their high energy density and extraordinary CO2 capture capability. However, the advancement of metal–CO2 batteries is still at an early stage. The problems caused by accumulation of carbonates during charge–discharge cycles, such as large polarization and poor reversibility, restrict their practical application. Therefore, designing efficient catalysts is crucial for promoting the decomposition of carbonate to improve the electrochemical performance of metal–CO2 batteries. Herein, we first adopted sea urchin-like γ-MnO2 as the cathode material for Li/Na–CO2 batteries. Benefiting from the unique structure and excellent catalytic activity of γ-MnO2, the as-prepared Li–CO2 and Na–CO2 batteries can achieve low overpotentials of 1.28 and 1.36 V, respectively, at a current density of 100 mA g–1 with a cutoff capacity of 1000 mA h g–1. The overpotentials are lower than those of most of the state-of-the-art catalysts in previous reports. After 100 and 50 cycles of Li–CO2 and Na–CO2 batteries, respectively, their charging termination voltages remain at around 4.1 and 3.9 V, respectively; such a low charging platform indicates the excellent catalytic activity of the γ-MnO2 cathode on the discharge products. Our findings offer a promising guideline to design efficient electrocatalysts for high-performance metal–CO2 batteries.
研究领域:
材料科学
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电化学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Yaoyang Xia,Hao Xiang,Fu Wan,Ruiqi Liu,Kaida Hu,Yujie Zheng,Quan Zhou,Weigen Chen
Aqueous zinc ion batteries (AZIBs) with MnO 2 as the positive electrode have attracted extensive attention due to their high theoretical energy density. However, the dissolution of the positive electrode and the poor conductivity during the cycling process affect its development prospects. In this paper, δ-MnO 2 with larger interlayer spacing is adopted, and pre-intercalation of Ni 2+ is used to further expand its interlayer spacing to enhance the diffusion kinetics of Zn 2+ in the cathode. Density functional theory (DFT) calculations show that the charge distribution around Mn and O atoms will be changed to improve the conductivity of the MnO 2 cathode by the Ni 2+ intercalation. However, the intercalation of metal cations will lead to the production of more Mn 3+ . which will lead to further manganese dissolution. Therefore, we prepared a polyindole (PIn) coating layer with high conductivity and can effectively prevent cathode erosion by in-situ polymerization. The formation of a heterogeneous interface between PIn and MnO 2 surface not only provides more active electrochemical sites, but also enhances the conductivity of the cathode and reduces the occurrence of manganese dissolution, which greatly improves the cycle performance and specific capacity of the cathode. Ni-MnO 2 @PIn delivers a discharge capacity of 385 mAh g −1 at a current density of 0.1 A g −1 , and maintains a capacity of 278 mAh g −1 after 200 cycles at a current density of 0.3 A g −1 , with a capacity retention of 95 %.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2024
·
IF 3.7
Jing Li,Hui Sun,Dewei Zhang,Xiaodong Yang,Zhuan Fu,Bin Yu
Previous studies have confirmed that MnOx removes heavy metal ions and organic pollutants from water with dual effects of adsorption and oxidation coupling, significantly improving the ability to remove impurities. Nanometal oxides have a highly reactive surface but tend to agglomerate during preparation and are challenging to recycle after use. A common method is to combine nano-MnO2 with Fe3O4 to prepare magnetic materials for easy recycling. Our previous research has confirmed that catechol (CA) and (3-aminopropyl) triethoxysilane (KH550) can be co-deposited on the surface of polypropylene nonwovens to form a stable CK coating under alkaline conditions. In addition, the coating has many active groups, including hydroxyl groups, amino groups, etc. This study further investigates the secondary reactivity of CK coatings. The coordination of catechol groups and metal ions was used to anchor manganese ions to the coating. Meanwhile, the hydroxyl and amino groups were used to reduce manganese ions to Mn4+ in situ to prepare PP-(CK-MnO2). We found that the sample had an excellent decolorization effect on cationic dyes but was limited to anionic dyes. The decolorization mechanism of cationic dyes was further discussed. The results showed that the decolorization of cationic dyes had a dual effect of adsorption and oxidative degradation. Under acidic conditions, its oxidation properties were enhanced. It can be used as a highly effective decolorizing agent for cationic dyes, and the decolorization behavior is consistent with the first-order kinetics. As the pH increases, its oxidation properties gradually decrease. Although the electrostatic adsorption effect was enhanced, the overall decolorization performance was significantly reduced. Recycling experiments have proved that it can maintain >90% removal rate after five cycles. This study also demonstrated that the CK coating has dopamine-like properties, which can coordinate with metal ions to prepare metal–organic hybrid materials.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Jianhui Zhao,Jie Liu,Ning Li,Wei Wang,Jun Nan,Zhiwei Zhao,Fuyi Cui
In this study, magnetic Fe 3 O 4 -MnO 2 nanoplates were successfully synthesized by a facile hydrothermal process in order to remove bivalent heavy metals from water. The Fe 3 O 4 part facilitated the reclamation of the adsorbent. Meanwhile, the modification by amorphous MnO 2 could significantly enhance the specific surface area of Fe 3 O 4 -MnO 2 and decrease the point of zero charge, thus ensured the good adsorption capacity for metal cations. The adsorption isotherms and kinetics of the five metal ions on Fe 3 O 4 -MnO 2 and the pH effect on removal efficiency were detailedly investigated. Sips isotherm was the most suitable model to describe Pb 2+ , Cu 2+ , Cd 2+ and Zn 2+ adsorption on Fe 3 O 4 -MnO 2 , while Temkin, Redlich-Peterson and Langmuir models showed a higher fitting degree for Ni 2+ . The adsorption capacities of Pb 2+ , Cu 2+ , Cd 2+ , Zn 2+ and Ni 2+ on Fe 3 O 4 -MnO 2 were 208.17, 111.90, 169.90 100.24 and 55.63 mg/g, respectively. Kinetic data were better fitted to pseudo-second-order model ( R 2 > 0.99), indicating a dominant role of chemisorption. Further analysis of infrared spectra demonstrated that the adsorption process was achieved mainly by ion exchange and complexation. The adsorption rates and preference ranking of metal ions on Fe 3 O 4 -MnO 2 were in the same order: Pb 2+ > Cu 2+ > Cd 2+ > Zn 2+ > Ni 2+ . Moreover, the adsorbent showed good recyclability and excellent ability of neutralizing the solutions by surface protonation and deprotonation. Overall, the reported results here have significant implications for removing metal cations from water in practice.
研究领域:
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
Surfaces and Interfaces
·
2022
·
IF 6.137
Lang Wang,Xinyu Wang,Binxin Song,Zhe Wang,Linlin Zhang,Qiongqiong Lu
MnO 2 is a type of ideal cathode material for aqueous zinc-ion batteries (ZIBs) owing to reasonable price, innocuity, and environmental friendliness. Nevertheless, it plagued by the dissolution of manganese ions and poor electrical conductivity . Therefore, designing and fabricating high-performance MnO 2 based cathode materials are essential for the development of ZIBs. In this work, poly(3,4-ethoxylenedioxythiophene) coated MnO 2 (MnO 2 @PEDOT) is in situ fabricated by mixing 3,4-ethoxylenedioxythiophene (EDOT) and KMnO 4 solution to restrain the dissolution of manganese ions, enhance the electronic conductivity and structural stability. As a result, MnO 2 @PEDOT composite possesses superior electrochemical performance . An outstanding capacity of 242 mA h g –1 at 0.2 A g –1 was reached, and eminent long-term stable cycling performance above 1000 cycles with the capacity retentions of 85.1% at 2 A g –1 was achieved. This study demonstrated a facile in situ synthesis strategy of MnO 2 @PEDOT, and it showed a promising potential for practical application.
研究领域:
材料科学
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电化学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
Progress in Natural Science-Materials International
·
2023
·
IF 4.7
Siyi Wang,Yuxuan Bai,Zhixiong Zhang,Chengde Xie,Wenhui Song,Chen Wang,Zhuoyu Ji,Jianjun Wang
In this study, the one-dimensional nanomaterial α-MnO 2 @ZIF-8 was satisfactorily fabricated using a simple hydrothermal method by modifying ZIF-8 on α-MnO 2 nanowires for high-performance extraction of U(VI) out of water solution. The experimental data indicated that the adsorption of U(VI) on α-MnO 2 @ZIF-8 was intensely dependent on solution pH but not on ionic strength . The maximum adsorption of U(VI) on α-MnO 2 @ZIF-8 at pH = 5.0 and T = 298 K was 802.36 mg/g, substantially higher than the adsorption on α-MnO 2 (22.32 mg/g) or ZIF-8(551.31 mg/g) under the same conditions, indicating that the performance of the modified α-MnO 2 was greatly enhanced. Attaining adsorption equilibrium within 45 min, the analytical kinetic process of α-MnO 2 @ZIF-8 indicated that its adsorption on U(VI) was monolayer chemisorption . The adsorption experiments and XPS analyzed the possible adsorption mechanism of U(VI) in the reaction with α-MnO 2 @ZIF-8 during the adsorption process , namely intra-sphere surface complexation, chemisorption and electrostatic interaction . The simple preparation and high removal efficiency of α-MnO 2 @ZIF-8 indicated that this adsorbent had good prospects for application in wastewater.
研究领域:
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
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Zeming Wang,Zihao Wang,Wei Li,Yeqing Lan,Cheng Chen
The hybrids of Co 3 O 4 anchored on different crystallographic MnO 2 (α-MnO 2 @Co 3 O 4 , β-MnO 2 @Co 3 O 4 , γ-MnO 2 @Co 3 O 4 , and δ-MnO 2 @Co 3 O 4 ) were synthesized and applied in peroxymonosulfate (PMS) activation for the degradation of sulfisoxazole (SIZ). Various characterizations were conducted to explore the physicochemical properties of the hybrids, and their catalytic activities were compared. The SIZ degradation followed pseudo-first-order kinetics, and the rate constants ( k obs ) were 0.1135, 0.0307, 0.1080, and 0.0285 min −1 for α, γ, β, and δ-MnO 2 , respectively. The introduction of Co 3 O 4 greatly improved the catalytic activities of the MnO 2 hybrids, and more than 94.7% of SIZ was degraded within 20 min. The k obs was in the order of γ-MnO 2 @Co 3 O 4 (0.3952 min −1 ) > α-MnO 2 @Co 3 O 4 (0.1573 min −1 ) > β-MnO 2 @Co 3 O 4 (0.1536 min −1 ) > δ-MnO 2 @Co 3 O 4 (0.1319 min −1 ). Obviously, the synergy of Co 3 O 4 and MnO 2 weakened the differences of catalytic performance of MnO 2 caused by their microstructures among α, β, and δ-MnO 2 . Due to its large surface area, γ-MnO 2 @Co 3 O 4 exhibited the most excellent catalytic performance for the SIZ removal. All the hybrids also displayed superior stability and reusability, and the degradation rates of SIZ maintained were above 97% during five consecutive cycles. The reactive oxygen species (ROS) including SO 4 •− , • OH, and 1 O 2 were responsible for the SIZ degradation in the system of MnO 2 @Co 3 O 4 /PMS, which was confirmed by electron paramagnetic resonance (EPR) technique and scavenger tests. Twelve intermediates of the SIZ degradation were identified via HPLC-TOF-MS 2 . Combined with the results of characterizations together with ROS identification, the possible catalytic mechanisms and pathways of the SIZ degradation were proposed. This study may shed some light toward the application of different crystallographic MnO 2 hybridized with other transition metals in PMS activation .
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2025
·
IF 5.1
Bei Li,Xiaoran Zhang,Xincheng Sun,Peng Lei,Ruyu Li,Chuan Dong,Shaomin Shuang
A tumor microenvironment responsive nanoarchitecture was designed for glutathione (GSH) sensing and synergistic photothermal/photodynamic therapy. Using polymer dots as both templates and reductants, MnO 2 was coated on their surface via in-situ reaction to harvest fluorescence PDs@MnO 2 nanoprobes. The photosensitizer methylene blue doped polypyrrole nanocomposites were synthesized by one-pot method, and further modified with silica to prepare PPy@MB-SiO 2 nanocomposites, PPy@MB-SiO 2 /PDs@MnO 2 nanoarchitecture was finally constructed based on electrostatic interaction. MnO 2 was responsible for the fluorescence quenching of PDs through fluorescence resonance energy transfer, while GSH induced the degradation of MnO 2 to promote fluorescence recovery. A fluorescence sensing GSH method was thus established, the fluorescence intensity of this nanoarchitecture exhibited a linearity in GSH concentrations range from 1 to 250 μmol·L −1 with a detection limit of 0.16 μmol·L −1 (3σ). MnO 2 also ensured the amelioration of tumor hypoxia, hence more 1 O 2 was generated to improve photodynamic therapy effect. Polypyrrole was in charge of photothermal performance that bestowed this nanoarchitecture with 31.45 % of photothermal conversion efficiency. Particularly, this platform was able to distinguish cancer cells and normal cells. The overexpression of GSH in HeLa cells stimulated fluorescence recovery, while only weak fluorescence was observed in Raw cells, this platform thus realized the fluorescence imaging recognition of cancer cells. The combined therapy effect was further harvested under 808 and 635 nm laser irradiation. The integration of fluorescence imaging, photothermal and photodynamic therapy in one platform that satisfied the need of cancer diagnosis and treatment. This strategy had reference significance for the assembly of multi-responsive therapy architectures.
研究领域:
生物医学工程
·
肿瘤学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2020
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IF 3.232
Bicheng Liu,Zoujun Peng,Sihao Wu,Tianshuang He,Ping Qiu
In this paper, a novel fluorescence assay has been constructed for the determination of parathion-methyl (PM) by using 4-amino-3-hydroxy-1-naphthalenesulfonic acid (AHNSA) as probe. MnO 2 nanosheets (MnO 2 NS) could quench the fluorescence of AHNSA, while Mn 2+ , the reduction product of MnO 2 NS, has no influence on it, resulting in fluorescence recovery. This is because that MnO 2 NS have oxidized characteristic, and they can react with choline (TCh), which is the product of acetylthiocholine (ATCh) catalyzed by acetylcholinesterase (AChE). In the presence of OPs, the activity of AChE was inhibited, accompanied by the restraint of the redox reaction of MnO 2 NS, therefore the fluorescence of AHNSA was quenched. Under the optimized experimental conditions, a linear range of PM was determined to be 0.4–40 ng/mL (R 2 = 0.997) by the proposed method with the limit of detection for 0.18 ng/mL (S/N = 3). The assay was successfully applied to the determination of PM in lake water, which average recoveries were between 86.5% and 114.4%.
研究领域:
分析化学
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环境科学
·
毒理学
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2020
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IF 3.807
Jing Wu,Xiaowei Chi,Yunzhao Liu,Jianhua Yang,Yu Liu
Aqueous zinc-ion batteries (AZIBs) based on MnO 2 cathode and Zn anode has attracted an increased attention for energy storage for their low cost, high safety and environmental friendliness . However, the essentially poor conductivity and unstable structure change of MnO 2 cathode during electrochemical reaction usually lead to low discharge capacity and rapid fading for AZIBs. To alleviate these problems, a hollow urchin-like MnO 2 was synthesized by a modified one-step hydrothermal method . The as-proposed unique morphology with large surface can effectively shorten the ion diffusion distance and alleviate the collapse of the structure. The urchin-like MnO 2 cathode shows a high reversible specific capacity of 324.9 mAh g −1 at 0.1 A g −1 (0.32C). Meanwhile, a long-term stability up to 5000 cycles with a retained capacity of 124 mAh g −1 at a high current density of 1.5 A g −1 (5C) is obtained, which is obviously superior to a common spherical MnO 2 . Ex-situ analysis reveals a H + and Zn 2+ co-insertion reaction mechanism for the as-obtained cathode. The remarkably electrochemical performance suggests the hollow urchin-like MnO 2 a promising cathode for AZIBs.
研究领域:
材料科学
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电化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2021
·Vol. 50
·期 31
·10838-10844
·
IF 4.39
Xia Xu,Meirong Fu,Penghui Li,Min Yang
While photothermal therapy is widely applied in phototherapy, there are still challenges in developing new generation phototherapy materials with precise diagnostic functions. Here we report the construction of a pH responsive upconversion fluorescence imaging precisely guided photothermal therapy system, namely NaYF4:Yb3+/Er3+@NaYF4@MnO2@Au nanocomposites, which can effectively avoid light damage to non-target tissues. Owing to the fluorescence resonance energy transfer between the upconversion nanocrystal donor and MnO2 and Au acceptor, the upconversion fluorescence is completely quenched. However, in pH 5.3 PBS buffer, MnO2 is gradually broken down, and the upconversion fluorescence is partially recovered, which could be used for upconversion fluorescence imaging to precisely guide photothermal therapy under 980 nm excitation. Simultaneously, due to the absorption of 980 nm excitation light and the emission bands of Er3+ (2H11/2 → 4I15/2 and 4S3/2 → 4I15/2 transition), temperature increment of core@shell@MnO2@Au could reach 35.5 °C under 980 nm excitation at 0.8 W cm−2. The core@shell@MnO2@Au nanocomposites are supposed to contribute significantly in the biological applications of photoluminescence imaging and photothermal therapy.
研究领域:
生物医学工程
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纳米医学
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光疗技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 57
·45646-45653
·
IF 3.84
Suqin Liu,Huizhen Liu,Guanhua Jin,Hao Yuan
A novel flower-like MnO2/BiOI composite has been fabricated by a simple and cost-effective approach. Multiple experiments are carried out to optimize the molar ratio of MnO2/BiOI for the decomposition of methyl orange (MO) and Rhodamine B (RhB). The adsorption property of the as-prepared samples in dark conditions and the photocatalytic activity under visible light and simulated solar light irradiation are investigated in detail. When the MnO2/BiOI molar ratio is 4 : 5, the highest photocatalytic activity for degradation of MO (97.8%) and RhB (91.7%) is achieved under visible light irradiation for 40 min as well as simulated solar light irradiation (93.4% for MO and 88.2% for RhB within 40 min). The excellent photocatalytic performances are attributed to the synergistic effect of BiOI and MnO2 and the unique flower-like morphology of the MnO2/BiOI composite as verified by relative experiments.
研究领域:
材料科学
·
环境科学
✓ 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）