Batteries & Supercaps
·
2025
·
IF 4.7
Xu Zhang,Heng Xiang,Chuang Pang,Keyu Zhao,Zhongli Zou,Kui Cheng
The development of flexible energy-storage devices is limited by the poor conductivity, limited cycling stability, and slow electron/ion transport of metal oxides. Optimizing their structure and performance is crucial for advancing these technologies. Herein, a hollow cubic core–shell Co 3 O 4 @MnO 2 is synthesized via annealing and hydrothermal approaches. This composite enjoys advantages of the high electrical conductivity of Co 3 O 4 and the excellent pseudocapacitive properties of MnO 2 ; in addition, the hollow structure of the composite effectively mitigates the mechanical stress caused by volume changes during charge–discharge cycles. Owing to its large specific surface area and stable framework, Co 3 O 4 @MnO 2 achieves a high specific capacitance of 670.2 F g −1 and retains 83.18% of its initial capacitance after 10,000 cycles, demonstrating exceptional electrochemical stability and durability. Subsequently, an all-solid-state flexible supercapacitor was assembled using Co 3 O 4 @MnO 2 positive electrode and a negative electrode made of reduced graphene oxide hydrogel. The device achieves a high energy density of 78.2 W h kg −1 and a power density of 11,500 W kg −1 . Further, even after 10,000 charge–discharge cycles, it retained 73.1% of its initial capacitance, demonstrating potential for flexible energy-storage applications. This article highlights the advantages of Co 3 O 4 @MnO 2 in enhancing supercapacitor performance and offers insights for cost-effective cobalt-based energy-storage systems. Graphical The diagram illustrates the synthesis process of Co 3 O 4 @MnO 2 composites, in which a hollow core–shell structure is successfully constructed with Co 3 O 4 cages serving as the core and MnO 2 nanosheets as the shell.
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DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Yanhua Wu,Hong Wang
A CuMoO 4 /MnO 2 /tourmaline (CMT) heterogeneous photocatalyst was successfully constructed by hydrothermal method followed by calcination and applied to activate peroxymonosulfate (PMS) for organic contaminant degradation over a wide pH range under visible light illumination. The CMT catalyst exhibited impressive degradation efficiencies of tetracycline hydrochloride (TC, 93.48%), safranine T (SaT, 100%), acridine orange (AO, 99.46%), methyl orange (MO, 97.47%), neutral red (NR, 94.10%), trypan blue (TB, 93.67%), methylene blue (MB, 90.36%) and rhodamine B (RhB, 89.85%) within 50 min. The influence of related parameters including catalyst dosage, PMS concentration, initial pH value, TC concentration, coexisting ions, humic acid (HA) and different water matrices on TC degradation were systematically investigated. According to quenching experiments and electron paramagnetic resonance (EPR) tests, e − , SO 4 •− , •OH, •O 2 − and 1 O 2 all contributed to TC degradation, and •O 2 − played a predominant role in the photo-Fenton-like process. The reusability of CMT was evaluated by consecutive experiments, and comparable removal efficiencies could be maintained after five cycles. The degradation pathways of TC were deduced and the toxicity of degradation intermediates based on HPLC−MS detection was estimated by Toxicity Estimation Software (T.E.S.T.). Moreover, the catalytic degradation mechanisms of TC in CMT/PMS/Vis system were further proposed and the role of tourmaline was illustrated. This work opens an avenue for the construction of heterogeneous catalysts based on natural minerals in PMS/Vis coupling system for wastewater decontamination .
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2014
·Vol. 2
·期 48
·20729-20738
·
IF 0
Zhiwei Wen,Wen She,Yuesheng Li,Renchao Che
Enhancement of the electrochemical performances of electrode materials is a great challenge in the electrochemical capacitor field. Herein, a novel paramecium-like α-MnO2 hierarchical hollow structure used as an electrode material has been successfully prepared, which possesses an ultra-high specific surface area (285 m2 g−1), uniform crystal orientation, and high specific capacitance (554.3 F g−1 at 1 A g−1) and exhibits 97.9% capacitance retention after 5000 cycles. The earlier carbonaceous coating transformed from dopamine plays an important role in forming this novel paramecium-like morphology. The shells are constructed of ultra-thin α-MnO2 nanoflakes with highly uniform and preferentially exposed [001] crystal orientation. The high specific surface area increases the electrolyte–electrode contact area and the unique orientated structure effectively facilitates ion transportation. Quasi in situ electron energy-loss spectroscopy (EELS) analysis for both hierarchical hollow structures and commercial products at different charge–discharge stages indicates that Mn in our products can be almost completely restored to its original oxidation valence state due to a complete redox reaction, while there is still a fraction of Mn in the commercial product that cannot be restored, which causes the reduction of specific capacitance and retention. All the results suggest that this novel α-MnO2 hierarchical hollow structure with selective growth orientation might become an attractive type of electrode material.
研究领域:
材料科学
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电化学
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DOI
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Muhammad Arif,Ayaz Mahsud,Amjad Ali,Shipeng Liao,Jiawei Xia,Hai Xiao,Mohammad Azam,Tahir Muhmood,Zhansheng Lu,Yinjuan Chen
The construction of visible-light-driven hybrid heterostructure photocatalysts is of great significance for environmental remediation, although the utilization of strong visible-light response photocatalysts with high efficiency and stability remains a major challenge. On the other hand, defect engineering is an excellent way to introduce metal cation vacancies in materials, thereby ensuing in highly enhanced catalytic performance. Inspired by this, we effectively constructed a built-in interface α-MnO 2 /Bi 2 WO 6 heterostructure with abundant intimate interfaces and defective Mn 3+ /Mn 4+ active sites for photocatalytic tetracycline hydrochloride (TC-HCl), hexavalent chromium Cr 6+ reduction, and Escherichia coli ( E. coli ) inactivation. The experimental results, such as the active species test and X-ray photoelectron spectroscopy, indicated that the defective sites Mn 3+ /Mn 4+ , surface oxygen vacancies, and Bi (3+x)+ boosted the visible light absorption, and highly enhanced the photoinduced charge separation/transfer. Furthermore, experimental and DFT calculations reveal the high charge density at the built-in interface heterostructure and the Z-scheme charge transfer mechanism during the photocatalytic process. The results further reveal that O 2 − and 1 O 2 are the main reactive active species contributing to the photocatalytic reaction. The exceptional TC-HCl decomposition activity of the α-MnO 2 /Bi 2 WO 6 heterostructure (97.56%, 2.31, and 2.04 times higher than bulk), enhanced reaction kinetics (K app = 0.041 min −1 , 6.4, and 5.2 times higher than bulk), removal rate of 80.3%, Cr 6+ reduction to Cr 3+ (98.56%, K app = 0.0599 min −1 ), and almost 100% bacterial inactivation compared to bulk α-MnO 2 (42.22%) and Bi 2 WO 6 (47.76%), were mainly due to the enhanced charge separation/transfer at the built-in interface and high charge density. This study opens new horizons for constructing Z-scheme MnO-based interface heterostructures with abundant defect sites for exceptional photocatalytic applications.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2021
·Vol. 46
·期 3
·2737-2747
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IF 5.164
Yueheng Fan,Aiming Wu,Xiaohui Yan,Shuiyun Shen,Zhang Junliang
Summary Both the activity and structure of a cathode, when it is used in non-aqueous Li-O 2 batteries, play a prominent role in the aspects of durability and capacity. In this work, α-MnO 2 /prGO hybrid nanocomposites with a three-dimensional (3D) porous structure are proposed to act as the cathode to improve the battery performance. Highly active α-MnO 2 /prGO nanocomposites with different mass ratios are synthesized through a two-step template method and a subsequent annealing process. It is found that the optimal 50% α-MnO 2 /prGO cathode exhibits outstanding discharge capacity of 13 294 mAh g −1 under the condition of 100 mA g −1 . Meanwhile, with the limited capacity and currency density of 1000 and 100 mA g −1 , respectively, the battery maintains excellent durability for 239 cycles. Significantly, it is clear that the excellent electrochemical performance of the nanocomposites is strongly associated with the synergistic effect of their distinct porous architecture and the ORR/OER catalytic activity.
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
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
·
IF 9.136
Huihui Zhang,Sisi Xiao,Yansheng Du,Shilin Song,Kun Hu,Yuyue Huang,Huijuan Wang,Qiangshun Wu
Herein, dielectric barrier discharge (DBD) plasma and MnO 2 -cellulose acetate (MnO 2 /CA) composite films was coupled together to degrade sulfamethoxazole (SMX) in water. The MnO 2 /CA composite films were firstly prepared successfully though heating blending method in this study and then characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Raman spectra, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TG). Catalytic effect of the MnO 2 /CA films was investigated by comparing the removal percentages, the kinetic constants, the energy utilization efficiencies ( G 50 ) as well as the COD and TOC removal during the SMX degradation in the DBD plasma system with or without the MnO 2 /CA films addition under different reaction conditions. The optimal catalytic performance was obtained by adding the 3% MnO 2 /CA films into the DBD plasma system and the alkaline solution condition was favorable for the SMX degradation. After four times using, the MnO 2 /CA composite films still maintained the catalytic activity. Catalytic mechanism of the MnO 2 /CA films was speculated by analyzing the changes of solution pH and conductivity during the reaction, concentrations of the formed O 3 and H 2 O 2 in water and the generated active species ( 1 O 2 and ·OH) in both the DBD plasma system and the DBD-MnO 2 /CA films system. The quenching test was also carried out to figure out the important effect of the ·O 2 − , 1 O 2 and ·OH for the SMX degradation in the synergistic system. Finally, LC-MS was used to analyze the main intermediates generated during the SMX degradation and the possible degradation pathways were accordingly speculated. The research could provide a new direction for the development and application of the DBD plasma technology as well we the composite films catalyst.
研究领域:
环境科学
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材料科学
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化学工程
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DOI
高影响因子
Nanomedicine
·
2021
·
IF 5.307
Xi Li,Qi Wang,Sihui Yu,Minyi Zhang,Xijian Liu,Guoying Deng,Yuan Liu,Sufang Wu
Background: Radiosensitizers that can effectively consume glutathione provide broad prospects for enhancing the efficacy and reducing the side effects of radiotherapy. Aim: To explore the potential role of CuS@mSiO2@MnO2 nanocomposites in synergetic chemoradiotherapy. Methods: Nanocomposites were characterized by transmission electron microscopy, UV-Vis spectrometry and dynamic light scattering and were loaded with doxorubicin (DOX). The uptake and biodistribution of nanocomposites were observed by CCK8 assay, MRI and confocal laser scanning microscopy. The radiosensitization effect of nanocomposites and nanocomposites/DOX was assessed both in vitro and in vivo. Results:In vitro application of nanocomposites, with an average diameter of 30 nm and ζ-potential of 13.2 ± 0.4 mV, in combination with radiotherapy, depleted glutathione and induced ferroptosis and apoptosis. Nanocomposites/DOX exhibited tumor cell damage in vivo. Conclusion: We propose that this glutathione-depleting nanosystem could be a radiosensitizer as well as a drug transporter.
研究领域:
纳米技术
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肿瘤学
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放射生物学
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药学
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产品关联
DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
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2024
·
IF 10.7
Anni Cui,Lihua Dong,Yiting Hou,Xin Mu,Yu Sun,Huan Wang,Xiahua Zhong,Guiye Shan
Sensitive detection and effective inactivation of bacteria are essential in preventing foodborne bacterial infection that poses a significant threat to human health. Herein, a near-infrared (NIR)-driven multifunctional photoelectrochemical (PEC) biosensor was constructed for detection and inactivation of S. aureus . Based on the covalent bonding between amine and carboxyl groups, carboxyl-functionalized SA31 aptamer was immobilized on the PDA/MnO 2 photoelectrode. In the presence of S. aureus , SA31 aptamer can specifically capture S. aureus , causing the decrease of photocurrent signal owing to steric hindrance effect. Leveraging photocurrent-off signal, there existed a satisfied linear relationship between the photocurrent variation and the logarithm of S. aureus concentration, achieving a wide linear range from 10 to 10 7 CFU/mL with a low detection limit of 2.0 CFU/mL. Notably, PDA/MnO 2 with peroxidase-like activity facilitated the catalytic oxidation of S. aureus with assistance of hydrogen peroxide (H 2 O 2 ) to cause the inactivation of S. aureus . Desorption of inactivated S. aureus from the photoelectrode led to a recovery of photocurrent signal, enabling a "signal on" switch. Simultaneously, the excellent photothermal performance of the PDA/MnO 2 converted light energy into heat energy under the irradiation of NIR light (808 nm, 1.5 W/cm 2 ), triggering the synergistic antibacterial effect against S. aureus (97.36%). This work provides a novel strategy for fabricating the detection and inactivation of bacteria in practical applications.
研究领域:
生物传感技术
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微生物学
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食品安全
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医学工程
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产品关联
DOI
PubMed
高影响因子
VACUUM
·
2022
·
IF 4.11
Peng Deng,Hua Fang,Rui Liu,Xueyong Guo,Pengwan Chen
The development of novel catalysts with high-activity to improve the thermal-induced pyrolysis of energetic molecular perovskite is of great importance. In this work, flower-like MnO 2 nanostructure was fabricated by a facile hydrothermal method with KMnO 4 as only precursor, and its thermal-induced pyrolysis performance of energetic molecular perovskite DAP-4 was studied. Results showed the catalysis thermal-induced pyrolysis peak temperature of DAP-4 had reduced by 50 °C from 386 °C (raw DAP-4) to 336 °C (DAP-4/10 wt% MnO 2 ) by the flower-like MnO 2 nanostructure , with rich oxygen vacancy added. The heat release of DAP-4 thermal-induced pyrolysis processes had a trend of increasing from 3423 J/g to 3563 J/g first and then decreasing to 2223 J/g. The apparent activation energy of DAP-4 had been reduced to 144 kJ/mol with addition of 10 wt% MnO 2 . The catalysis mechanism of MnO 2 with flower-like nanostructure on thermal-induced pyrolysis of DAP-4 was provided.
研究领域:
材料科学
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催化化学
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产品关联
DOI
高影响因子
RSC Advances
·
2023
·Vol. 13
·期 44
·31067-31076
·
IF 3.9
Yaopeng Liu,Wei Zhao,Yi Gao,Qing Zhuo,Tingting Chu,Wensheng Huang,Yin Zheng,Yingru Li
Herein we report the colorimetry and an electrochemical for the determination of dopamine (DA) by using MnO2 nanoparticles and graphene nanosheets composite (MnO2@G) that display oxidase mimicking property. MnO2@G could directly oxidize colorless 3,3′,5,5′-tetramethylbenzidine (TMB) into a blue product (oxTMB) without extra oxidants such as H2O2. Nevertheless, the presence of DA will inhibit the TMB oxidation due to the presence of the competitive reaction of MnO2@G and DA, giving a product color change from blue to colorless. A colorimetric assay for detect the concentration of DA was worked out according to this finding. Response is linear in the 0.1 to 15 μM DA concentration range, and the detection limit is 0.14 μM. Wider detection range is achieved in an electrochemical method which is due to the pronounced electrocatalytic activity of MnO2@G. The MnO2@G was modified on the surface of the glassy carbon electrode in order to fabricate one type electrochemical sensor. The sensor achieves a wide detection two linear ranges from 0.4 to 70 μM, with the detection limit of 1.16 μM. The detection of DA in real serum sample proved that the nanozyme based on MnO2@G could be developed into a colorimetry and electrochemical dual-readout sensing platform.
研究领域:
生物传感器
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纳米材料
·
分析化学
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产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2017
·
IF 7.504
Longhai Jin,Jianhua Liu,Ying Tang,Lanqing Cao,Tianqi Zhang,Qinghai Yuan,Yinghui Wang,Hongjie Zhang
Construction of stimuli-responsive theranostic nanoagents that can increase the accuracy of imaging diagnosis and boost the therapeutic efficacy has been demonstrated for a promising approach for diagnosis and treatment of cancer. Herein, we constructed a novel theranostic agent with Co–P nanocomposites as core, mesoporous silica as shell, and manganese dioxide (MnO2) nanosheets as gatekeeper, which have been employed for pH-activatable T1/T2 dual-modality magnetic resonance imaging (MRI)-guided chemotherapeutical and photothermal combination anticancer therapy in vitro and in vivo. Co–P core-enabled theranostic platform could be applied for both photothermal therapy and T2-weighted MRI in the normal circulation owing to its strong near-infrared absorbance and intrinsic magnetic properties. In the acidic environment of tumors, MnO2 cap could be dissolved into Mn2+ ions to not only realize pH-responsive on-demand drug release but also activate T1-weighted MRI contrast enhancement. Such T1/T2 dual-mode MR imaging provides further comprehensive details and accurate information for tumor diagnosis, and the on-demand chemo-photothermal synergetic therapy greatly improved the therapeutic effectiveness and effectively mitigated side effects. These findings demonstrate that Co–P@mSiO2@DOX–MnO2 are promising as pH-responsive theranostic agents for tumor diagnosis and treatment, and stimulate interest in exploration of novel stimuli-responsive theranostic nanoagents which posssess good potential for clinical application in the future.
研究领域:
肿瘤学
·
纳米医学
·
影像医学
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产品关联
DOI
PubMed
高影响因子
NANO
·
2020
·
IF 1.566
Wentong Yang,Xiansen Yang,Xiang Li,Md. Zahidul Islam,Yubing Dong,Yaqin Fu,Xiangdong Liu,Feiya Fu,Yaofeng Zhu
In this paper, we designed a core@double-shell nanostructure to enhance the electromagnetic wave absorption performance of hybrid nanospheres. Herein, the core@double-shell structured Fe 3 O 4 @polyaniline@MnO 2 nanospheres were successfully prepared by a facile solvothermal process and in situ polymerization methods. The morphology, structure, magnetism and microwave absorption properties were studied. The results reveal that the FPM nanospheres exhibit extraordinary microwave absorbing performance compared to those of either Fe 3 O 4 or Fe 3 O 4 @polyaniline nanospheres. The minimum reflection loss of the FPM nanospheres is − 14.7 dB at 15.76 GHz with the thickness of 3.5 mm, and the corresponding effective absorption bandwidth can reach 4.75 GHz. The perfect EMW absorption of nanospheres can be ascribed to multi-interface polarization, multiple reflections and good impedance matching originated from the core@double-shell nanostructure.
研究领域:
材料科学
·
纳米技术
·
电磁工程
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DOI
高影响因子
危险品化学品经营许可证（带存储）