Journal of Materials Chemistry A
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2020
·Vol. 8
·期 25
·12586-12593
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IF 11.301
Cuiqin Fang,Dong Zhang
Recently, structural supercapacitors have attracted considerable attention due to their concurrent capability to store electrochemical energy and support mechanical loads. However, the greatest challenge in realizing an integrated electro-mechanical system is the development of highly compatible electrodes and structural electrolytes with superior mechanical and electrochemical performance. Here, a structural supercapacitor assembled with a 3D rGO@MnO2 nickel foam electrode and polyacrylic acid–Portland cement–KOH electrolyte is reported to solve the challenge for the first time. The resulting rGO@MnO2 electrode exhibits a high areal capacitance of 1.84 F cm−2 at 0.5 mA cm−2, with the areal capacitance remaining at 1.13 F cm−2 even at a current density of 40 mA cm−2. The structural electrolyte with 6 wt% polyacrylic acid–Portland cement–KOH shows the best combination of an ionic conductivity of 2.13 mS cm−1 and a compressive strength of 28.5 MPa. The resulting asymmetric structural supercapacitor with an areal capacitance of 51.5 mF cm−2 at 0.1 mA cm−2 is superior to those reported in latest studies based on carbon materials and resin, which suggests its potential application in structural energy storage for civil engineering.
研究领域:
材料科学
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能源工程
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Qun Yu,Yuhang Yang,Yan Xu,Yuqiao Wang,Qingdong Qin
The application of metal doping has emerged as a prominent approach for modifying transition-metal-based heterogeneous catalysts in activating peroxymonosulfate (PMS). Herein, silver-doped α-MnO 2 (Ag-α-MnO 2 ) was synthesized via a one-step hydrothermal approach and utilized for activating PMS to degrade sulfamethoxazole (SMX). The catalyst was systematically characterized and examined to determine that the efficient dispersion of Ag increased the specific surface area and pore volume of α-MnO 2 . The degradation experiments demonstrated that SMX could be efficiently degraded by a combination of PMS and Ag-α-MnO 2 within 60 min. The apparent kinetic rate constant was 0.039 min −1 , which was approximately ten times higher than that of α-MnO 2 . The impacts of external water conditions on catalytic performance and the stability of Ag-α-MnO 2 were subsequently investigated. Density functional theory calculations revealed that Ag as a crucial active center reduced the PMS adsorption energy, promoted electron transfer, and orchestrated electron distribution. EPR spectra, quenching experiments, electrochemical tests, and XPS analysis were performed to validate the radical and non-radical mechanisms, including SO 4 − , OH, O 2 − and 1 O 2 . The two redox cycles of Ag + /Ag 0 and Mn 4+ /Mn 3+ on the surface of Ag-α-MnO 2 contributed to the activation of PMS. Additionally, probable degradation pathways for SMX were presented. This study provides an initially valuable insight into the cooperative mechanism of PMS activation for SMX degradation employing Mn-based catalysts doped with precious metal silver.
研究领域:
环境科学
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催化化学
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材料科学
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DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2020
·
IF 6.551
Wenjing Zong,Zhaoming Guo,Minghuo Wu,Xianliang Yi,Hao Zhou,Siyuan Jing,Jingjing Zhan,Lifen Liu,Yang Liu
Endocrine-disrupting chemicals (EDCs) cause serious threats to human health. Five types of MnO 2 were synthesized and characterized. They exhibited different removal performances for three EDCs, i.e., estrone (E1), ethynylestradiol (EE2) and bisphenol A (BPA). Only δ-MnO 2 can completely remove E1 within 120 min at pH 3.0. Free Mn (III) was determined at the beginning of the reaction and participated in the EDCs removal process. Electron spin resonance (ESR) indicated that δ-MnO 2 could produce superoxide anions (·O 2 − ) and singlet oxygen ( 1 O 2 ) in the existence of methanol. The reactive oxygen species (ROS) quenching experiments showed 1 O 2 have certain contribution to the E1 removal by δ-MnO 2 . The source of ROS is mainly the lattice oxygen from δ-MnO 2 , and can be replenished through the layer structure destruction caused by the reaction between Mn(III) and E1. The ROS dependent EDCs removal by δ-MnO 2 leads to a deep understanding on this well-known oxidant.
研究领域:
环境科学
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化学工程
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水处理
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DOI
PubMed
高影响因子
MICROCHIMICA ACTA
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2021
·Vol. 189
·期 1
·1-10
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IF 5.833
Xing Yanyan,Chen Meiling,Zhao Yunkun,Xu Jiabi,Hou Xiaohong
Novel Fe 3 O 4 @C@MnO 2 composites were successfully synthesized for the first time via an interfacial reaction between magnetic porous carbon and KMnO 4 , in which the magnetic porous carbon was derived from the pyrolysis of Fe-MIL-88A under N 2 atmosphere. Interestingly, the obtained Fe 3 O 4 @C@MnO 2 composites were found to have triple-enzyme mimetic activity including peroxidase-like, catalase-like, and oxidase-like activity. As a peroxidase mimic, Fe 3 O 4 @C@MnO 2 composites could catalyze the oxidation of TMB into a blue oxidized product by H 2 O 2 . As a catalase mimic, Fe 3 O 4 @C@MnO 2 could catalyze the decomposition of H 2 O 2 to generate O 2 and H 2 O. As an oxidase mimic, Fe 3 O 4 @C@MnO 2 could catalyze the direct oxidation of TMB to produce a blue oxidized product without H 2 O 2 . Reactive oxygen species measurements revealed that the oxidase-like activity originated from 1 O 2 and O 2 − ∙and little∙OH generated by the dissolved oxygen, which was catalyzed by the Fe 3 O 4 @C@MnO 2 in the TMB oxidation reaction. The oxidase-like activity of Fe 3 O 4 @C@MnO 2 was investigated in detail. Under the optimized conditions, a rapid, sensitive, visual colorimetric method for dopamine detection was developed based on the inhibitory effect of dopamine on the oxidase-like activity. The proposed method allows for dopamine detection with a limit of detection of 0.034 μM and a linear range of 0.125–10 μM. This new colorimetric method was successfully used for the determination of dopamine in human blood samples. Graphical abstract
研究领域:
生物化学
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材料科学
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分析化学
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DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2022
·Vol. 33
·期 30
·23607-23622
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IF 2.779
Tong Lin,Wu Chunxia,Hou Junxian,Yan Jiayuan,Zhang Xiaoliang,Mu Jingbo,Wang Zehu,Wang Yanming,Che Hongwei,Zhang Zhixiao
Nano core–shell structured materials have different or better properties than single components, which can realize the design and optimization of nanoscale particle structure and properties. Additionally, hollow core–shell materials have the advantages of large specific surface area, abundant active sites, low density, short mass transfer path, and wide cavity structure, which are widely used in the fields of electrochemistry, biomedicine, and environmental protection. Herein, hollow core–shell FeOOH@MnO 2 nanorod composites were prepared by easiest hydrothermal method. Due to the synergy and versatility between the hollow FeOOH nanorods core and the MnO 2 nanosheets shell, the FeOOH@MnO 2 composite exhibits outstanding electrochemical characteristic as an electrode material with specific capacitance of 924 F g −1 at 1 A g −1 , admirable rate capability (capacitance retention of 75.9% from 1 to 10 A g −1 ), and remarkable cycling stability (91.2% of initial capacity retained after 5000 charge/discharge cycles). Notably, the assembled FeOOH@MnO 2 //activated carbon (AC) asymmetric supercapacitor facility possessed an energy density of 53.4 Wh kg −1 and a power density of 722 W kg −1 , indicating that the hollow core–shell FeOOH@MnO 2 nanorod nanocomposite is a viable electrode material that can be used in supercapacitors.
研究领域:
材料科学
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电化学
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纳米技术
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能源存储
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DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
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2020
·Vol. 167
·期 16
·160536
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IF 3.721
Yizhao Tang,Hao Cheng,Qinggang He,Hanyu Li,Yue An,Jian Xie,Ronghai Liu
Through a facile, stepwise approach that includes electropolymerization, calcination, a hydrothermal method and low-temperature adsorption, a carbon array was coated with RuO2/MnO2 to form a highly efficient composite catalyst (RuO2/MnO2@carbon array) for Li–O2 batteries. The unique, hierarchical, three-dimensional array-type structure facilitates electrode wetting and oxygen transport as well as providing a large volume for Li2O2 loading. The growth of MnO2 nanosheets on the carbon array surface alters the surface roughness and provides attachment sites for the subsequent loading of catalyst nanoparticles. In addition, the introduction of RuO2 induces the formation of Mn3+ on the surface of MnO2, which not only improves the electrode conductivity but also the catalytic activity for ORR/OER. As a result, conformal growth of thin layers of Li2O2 on the surface of the RuO2/MnO2@carbon array and reversible decomposition of Li2O2 during cycling were achieved. In comparison with cathodes without a carbon array or catalyst, the Li–O2 cell with a RuO2/MnO2@carbon array cathode exhibits an markedly improved performance with high discharge capacity (10 000 mAh g−1 at 100 mA g−1) and long cycling life (252 cycles at 200 mA g−1 with a limited capacity of 500 mAh g−1).
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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DOI
高影响因子
MICROCHIMICA ACTA
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2020
·Vol. 187
·期 3
·1-10
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IF 6.232
Zhu Wanying,Zhou Ying,Tao Mengdan,Yan Xiaoqiang,Liu Yan,Zhou Xuemin
A novel electrochemical and fluorescence dual-signal assay was developed for the determination of hydrogen peroxide (H 2 O 2 ) based on Fe 3 O 4 @MnO 2 and N-doped carbon dots (NCDs). Fe 3 O 4 @MnO 2 was not only applied as the recognizer for H 2 O 2 but also served as the fluorescence quencher and electrochemical enhancer. This permits the dual-signal readout of the analytical system. In the absence of H 2 O 2 , the NCDs were quenched by Fe 3 O 4 @MnO 2 , and the oxidation of the electrochemical probe ferrocene (Fc) was catalyzed by Fe 3 O 4 @MnO 2 . In the presence of H 2 O 2 , MnO 2 was reduced to Mn 2+ , leading to the fluorescence recovery of NCDs and the reduction in the oxidation signal of Fc. By combining the electrochemical method and the fluorescence assay, more comprehensive and valuable information for H 2 O 2 determination was provided to meet different analytical demands. The method exhibits good repeatability and selectivity with a detection limit of 1.0 μM for the fluorescence assay and 0.6 μM for the electrochemical method. The proposed approach holds great potential for probing released targets from living cells.
Graphical abstract
研究领域:
分析化学
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电化学
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荧光光谱学
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纳米材料
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产品关联
DOI
PubMed
高影响因子
Journal of Cleaner Production
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2017
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IF 5.715
Chao Zhang,Dongya Yang,Tao Zhang,Fengxian Qiu,Yuting Dai,Jicheng Xu,Zefeng Jing
Oil-absorbing materials with three-dimensional network structure are being actively investigated due to their application in the treatment of oil spills and chemical leakage which result from their controllable porous structures and swelling properties. In this work, the oil-absorbing MnO 2 /poly( n -butylacrylate- co -butyl methacrylate- co -methyl methacrylate) resin composite (MnO 2 /p(BA-co-BMA-co-MMA)) was synthesized by using a combined hydrothermal method and microwave polymerization method , and was successfully applied to absorb oils and organic solvents. In this synthesis, the MnO 2 hollow spheres were prepared via a simple hydrothermal method and modified by γ-methacryloxypropyl trimethoxysilane (KH-570) under microwave irradiation. Then, the MnO 2 /p(BA-co-BMA-co-MMA) hybrid resin with good oil absorption capacity and excellent recyclability were synthesized through suspension polymerization by a microwave polymerization route. The as-prepared samples were characterized by Fourier transmission infrared spectroscopy (FT-IR), X-ray diffraction (XRD), contact angle, scanning electron microscopy (SEM), etc. The as-prepared porous-structured MnO 2 that are comprised of individual microrods possess self-organized shaggy, ball-shaped architectures with sizes ranging from 2 to 4 μm. In order to obtain the hydrophobic surfaces, the surfaces of MnO 2 microspheres were chemically modified by KH-570 under microwave irradiation. And the surface of modified MnO 2 show high repellency towards water with a water contact angle of 135°. Moreover, the absorption properties of the MnO 2 /p(BA-co-BMA-co-MMA) hybrid resins were tested in this work. The results indicated that the oil absorption properties were strongly influenced by the content of MnO 2 hollow spheres. Furthermore, the MnO 2 /p(BA-co-BMA-co-MMA) hybrid resin has a maximum absorption capacities of 34.56 g*g −1 , 31.82 g*g −1 and 25.89 g*g −1 for the absorption of chloroform, carbon tetrachloride and toluene respectively and could selectively remove oils from water which is promising for their potential applications in oil spill cleanup.
研究领域:
材料科学
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环境工程
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产品关联
DOI
高影响因子
ACS Applied Nano Materials
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2022
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IF 6.14
Hongzhi Lu,Shoufang Xu
Nanoparticles are effective tools for signal amplification in chemical sensor construction. Herein, we present molecularly imprinted polymer (MIP)-based sandwich-structured fluorescence sensors for ultrasensitive detection of trace carcinoembryonic antigen (CEA) based on MnO2 nanosheet and MoS2 nanoflower dual signal amplification. MIPs were used as synthetic antibodies and prepared by a surface imprinting method using MnO2 nanosheet-loaded magnetic carbon fibers (CF/Fe3O4/MnO2) as solid supports by the self-polymerization of dopamine. The obtained CF/Fe3O4/MnO2/MIPs can specifically absorb the target CEA from complex samples, which can then be specifically labeled with boronic acid-modified MoS2-curcumin nanotags (BA-MoS2-CUR). Under alkaline conditions, CUR was detached from MoS2 and used as a fluorescence reporter molecule. Due to the high binding capacity of the MnO2 nanosheets and the high loading capacity of the MoS2 nanoflowers, the detection sensitivity of the molecularly imprinted fluorescence sensors was remarkably improved. Specific detection of CEA in the linear range of 0.01 ng/mL–10 μg/mL with a low LOD of 3.5 pg/mL (S/N = 3) was achieved. In addition, based on the MIPs and boronic affinity dual specific recognition ability, the detection selectivity was also improved. Finally, the concentration of CEA in human serum was determined by this approach.
研究领域:
生物化学
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医学诊断
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材料科学
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
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2024
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IF 5.4
Zhen Jin,Yunkai Wang,Miaomiao Han,Li Wang,Fei Lin,Qianfang Jia,Wu Ren,Jiawei Xu,Wenhao Yang,Guo-an Zhao,Xuming Sun,Changqin Jing
Tumor microenvironment (TME)-responsive size-changeable and biodegradable nanoplatforms for multimodal therapy possess huge advantages in anti-tumor therapy. Hence, we developed a hyaluronic acid (HA) modified CuS/MnO 2 nanosheets (HCMNs) as a multifunctional nanoplatform for synergistic chemodynamic therapy (CDT)/photothermal therapy (PTT)/photodynamic therapy (PDT). The prepared HCMNs exhibited significant NIR light absorption and photothermal conversion efficiency because of the densely deposited ultra-small sized CuS nanoparticles on the surface of MnO 2 nanosheet. They could precisely target the tumor cells and rapidly decomposed into small sized nanostructures in the TME, and then efficiently promote intracellular ROS generation through a series of cascade reactions. Moreover, the local temperature elevation induced by photothermal effect also promote the PDT based on CuS nanoparticles and the Fenton-like reaction of Mn 2+ , thereby enhancing the therapeutic efficiency. Furthermore, the T 1 -weighted magnetic resonance (MR) imaging was significantly enhanced by the abundant Mn 2+ ions from the decomposition process of HCMNs. In addition, the CDT/PTT/PDT synergistic therapy using a single NIR light source exhibited considerable anti-tumor effect via in vitro cell test. Therefore, the developed HCMNs will provide great potential for MR imaging and multimodal synergistic cancer therapy.
研究领域:
生物医学工程
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纳米医学
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肿瘤治疗
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产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2023
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IF 5.9
Jinyu An,Xue Jiang,Qian Wu,Zhiru Zou,Yingqiao Li,Junpeng Sun,Xiaobang Liu,Ying Xiong,Chao Wu,Xifan Mei,He Tian
Secondary injury following spinal cord injury (SCI) results in a large production of reactive oxygen species (ROS) (e.g., H2O2) in the spinal cord microenvironment, which then leads to an excessive burst of inflammation and ultimately neuronal death. In this study, we prepared manganese dioxide (MnO2) nanoparticles coated by macrophage membranes, named M@MnO2, to cope with early ROS bursts in the SCI microenvironment. The biosafety and targeting ability of the MnO2 nanoparticles were improved through the macrophage membranes. Successful preparation of M@MnO2 was verified by transmission electron microscopy, Western blot, and dynamic light scattering. Small animal imaging showed that M@MnO2 accumulated in large quantities at the site of SCI. In the early stages of SCI, M@MnO2 effectively reduced the ROS content, as well as the hypoxia-inducible factor 1α (HIF-1α) content, malondialdehyde content, and superoxide anion content caused by ROS, further leading to a decrease in some of the proteins associated with inflammation at the site of SCI (CD11b, CD86, COX2, IL-1β, and iNOS), ultimately achieving neuroprotection and recovery of motor function.
研究领域:
纳米技术
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神经科学
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生物材料
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药理学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Yang Zong,Yufei Shao,Wenjie Ji,Yunqiao Zeng,Jun Xu,Wen Liu,Longqian Xu,Deli Wu
Traditional advanced oxidation processes (AOPs) generally suffer from the inevitable deactivation of catalysts and the ineffective consumption of transient reactive species (TRSs) that compromise the efficiency in destructing aqueous contaminants. Herein, it was interestingly found that trace Mn(II) could robustly catalyze the oxidation of organic contaminants by periodate (PI), with the performance was much better than the representative TRSs-dominated AOPs (i.e., the Fe(II)-activated hydrogen peroxide, peroxymonosulfate (PMS), peroxydisulfate and PI processes). Multiple lines of evidence excluded the oxidative contributions of TRSs, instead the stoichiometric formation of colloidal MnO 2 via the condensation of di-μ-oxo-bridged Mn(IV) cluster was confirmed by UV-vis, X-ray absorption near edge structure spectroscopy and density functional theory calculation. Dependent on the structure of substrate, MnO 2 colloids solely or simultaneously served as oxidant and catalyst for the enhanced treatment performance. Benefiting from the non-TRSs-involved oxidation strategy and the catalytic effects of Mn species, the trace-Mn(II)/PI process even outperformed the Co(II)-activated PMS counterpart (i.e., one of the most efficient AOPs known at present) on oxidant utilization efficiency. This study not only elucidated the roles of Mn(II) and colloidal MnO 2 in PI-mediated contaminant degradation, but also signified the superiority of trace catalyst-assisted process without TRSs involvement in avoiding undesired side reactions and maximizing oxidation efficiency.
研究领域:
环境科学
·
化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）