Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Pijun Gong,De Fang,Feng He,Junlin Xie,Haitao Wu
Cake-like MnO 2 @CeO 2 catalyst with hierarchical nanosheets structure has been successfully constructed by in situ methods. The relationship between structure and activity of the MnO 2 @CeO 2 catalyst was characterized using various analytical techniques. It is identified that rich surface oxygen species and better reducibility were generated due to the strong synergistic effect between MnO 2 and CeO 2 , and hence nearly T 90 toluene conversion can be obtained for the 10%-MnO 2 @CeO 2 catalyst under 240–300 °C. In addition, it is found that after loading MnO 2 on the multi-layer CeO 2 support to form a hierarchical cake-like structure, the oxygen vacancies, Ce 3+ /Ce 4+ and BET surface area of MnO 2 @CeO 2 increased significantly, which is beneficial to toluene adsorption and reaction. Furthermore, the in situ DRIFTS study demonstrated that the lattice oxygen and surface oxygen both participate in the toluene oxidation , whereas surface active oxygens adsorbed on the oxygen vacancies will lead to deep oxidation by forming abundance intermediates.
研究领域:
催化化学
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环境科学
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产品关联
DOI
高影响因子
Biosensors-Basel
·
2025
·Vol. 15
·期 1
·49
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IF 5.6
Yijiong Xue,Chengqi Bao,Hui Liu,Fanghui Ma,Minghui Yang,Xiaoqing Li
A fluorescence probe for “switch-on” detection of alkaline phosphatase (ALP) was developed based on Au nanoclusters anchored MnO2nanosheets (Au NCs-MnO2NSs), which were synthesized using bovine serum albumin (BSA) as template through a simple one-pot approach. In the sensing system, MnO2NSs function as both energy acceptors and target identifiers, effectively quenches the fluorescence of Au NCs via fluorescence resonance energy transfer (FRET). The presence of ALP catalyzes the hydrolysis of L-ascorbic acid-2-phosphate (AAP) to ascorbic acid (AA), reducing MnO2NSs to Mn2+and facilitate the fluorescence recovery of Au NCs. The fluorescence assay offers the advantages of facile preparation, cost-effectiveness, good specificity, and high sensitivity. Moreover, the assay exhibits a broad linear range (0.005 U/mL to 8 U/mL) for ALP detection with a remarkable limit of detection of 0.0015 U/mL. Notably, this assay demonstrates promising applicability for detection ALP in human serum samples, thereby providing valuable potential for clinical applications.
研究领域:
生物化学
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分析化学
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医学检测
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2020
·Vol. 167
·期 6
·066515
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IF 3.721
Wenjing Liu,Zhiyuan Wu,Pei Dong,Feifei Lin,Meng Zang,Shuai Qiao,Yingying Gu,Jinqiang Zhang,Shuaijun Wang,Chaocheng Zhao
Developing effective and economical materials for emerging electrochemical remediation of persistent organic pollutants has attracted significant research interest. In this study, a heteromorphic self-standing nickel foam@Ni(OH)2/MnO2 (NF@Ni(OH)2/MnO2) electrode was synthesized by a simple solvothermal method and employed for the remediation of persistent organic pollutants. The prepared NF@Ni(OH)2/MnO2 electrode exhibited better performance for the electro-catalytic degradation of tetracycline (TC) than that of the NF and NF@Ni(OH)2. In optimized conditions, the NF@Ni(OH)2/MnO2 electrode exhibited the highest TC degradation efficiency (90%) and total organic carbon(TOC) removal (59.02%) among the prepared electrodes. In addition, a higher mineralization current efficiency (MCE) and lower energy consumption (EC) for the NF@Ni(OH)2/MnO2 electrode was achieved. The enhancement occurs primarily because the active MnO2 anchored to the porous and highly conductive Ni foam substrate surface boosts the electron transfer and the generation of hydroxyl radicals, as proved by a free radical trapping experiment and fluorescence spectrum analysis. This study suggests the possibility of a new paradigm in designing effective and practical electro-Fenton electrodes for environmental remediation.
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
CERAMICS INTERNATIONAL
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2019
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IF 3.45
An-Nan Chen,Jing-Yan Chen,Jia-Min Wu,Li-Jin Cheng,Rong-Zhen Liu,Jie Liu,Ying Chen,Chen-Hui Li,Shi-Feng Wen,Yu-Sheng Shi
Novel double-shell mullite powders with good flowability and formability for selective laser sintering (SLS) were prepared for the fabrication of porous mullite ceramics with enhanced mechanical properties. The inner MnO 2 shell was prepared by the co-precipitation reaction between MnC 4 H 6 O 4 ·4H 2 O (Mn(Ac) 2 ·4H 2 O) and KMnO 4 , and the outer phenolic resin shell was obtained via the solvent evaporation method. The influence of Mn(Ac) 2 ·4H 2 O solution content on phase composition, microstructure, pore size distribution and mechanical properties of porous mullitie ceramics was investigated. With increasing Mn(Ac) 2 ·4H 2 O content from 0 to 48 mL, the compressive strength and fracture toughness of porous mullite ceramics increased from 0.8 ± 0.1 MPa to 22.1 ± 1.0 MPa and from 0.03 ± 0.01 MPa m 1/2 to 0.53 ± 0.01 MPa m 1/2 , respectively. It was found from TEM analysis that the remarkable mechanical property enhancement was attributed to the pinning effect of the presence of MnO 2 sintering additive precipitated between the interwoven mullite grains. Correspondingly, the shrinkage increased sharply from 5.27 ± 1.3% to 23.5 ± 1.4%, while the open porosity decreased dramatically from 64.1 ± 0.6% to 48.7 ± 1.2% with the gradual reduction of open pore size distribution from 17.25 to 11.33 μm. Finally, the honeycomb mullite ceramics with very complex shapes of intersecting pore tunnels were successfully prepared by SLS. This paper provide a novel and feasible route to dramatically improve the mechanical properties of SLS-formed porous ceramic products.
研究领域:
材料科学
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陶瓷工程
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2016
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IF 3.014
Mingtao Qiao,Xingfeng Lei,Yong Ma,Lidong Tian,Wenbin Wang,Kehe Su,Qiuyu Zhang
Functional composite microspheres with porous Fe 3 O 4 cores and hierarchical MnO 2 shells have been synthesized successfully via a two-step hydrothermal method . X-ray diffraction was employed to determine the crystal forms of samples. The morphologies and microstructures of Fe 3 O 4 nanoparticles and Fe 3 O 4 @MnO 2 composite microspheres were observed by the scanning electron microscope and transmission electron microscope. It can be seen that hierarchically structured MnO 2 shells have coated Fe 3 O 4 nanoparticles, and the shell thickness is about 140–160 nm. The BET specific surface area and porosity were estimated by the N 2 absorption-desorption isotherms and the magnetic properties were measured by the vibrating sample magnetometer . As-synthesized Fe 3 O 4 @MnO 2 composite microspheres have a BET specific surface area of 167 m 2 /g, and the pore width is mainly distributed in the mesoporous range, especially from 2.0 nm to 12.0 nm. Investigations of microwave absorbing properties manifest that Fe 3 O 4 @MnO 2 composite microspheres with loading 10% weight fraction possess the strongest RL peak of −42.6 dB (5.7 GHz) at the matching thickness 4.0 mm, and Fe 3 O 4 @MnO 2 composite microspheres with loading 20% weight fraction have a broader absorbing bandwidth (10.2–15.0 GHz and 15.5–17.3 GHz) at the matching thickness 1.5 mm. Achieving the advantages of intensive absorption, wide effective absorbing bandwidth band and intrinsic lightweight feature, porous core-shell Fe 3 O 4 @MnO 2 composite microspheres are believed to be more promising in the application of microwave absorption.
研究领域:
材料科学
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纳米技术
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Yuan Zhang,Dong Wang,Gaili Liu,Kun Wang,Shaomin Shuang,Chuan Dong
2-Mercaptobenzothiazole (MBT), commonly employed in the rubber and metal industries, poses a significant environmental hazard, detrimental effects on aquatic ecosystems and potential carcinogenicity in humans. Urgent measures are warranted to develop practical strategies for MBT analysis and mitigation. This study introduces a novel nanozyme sensor, orderly consistent with dendritic mesoporous silica nanoparticle (DMSN), CuO nanoparticle cargo, and MnO 2 shell (designated as DMC), engineered for both MBT detection and degradation. By harnessing oxidase-like MnO 2 and peroxidase-like CuO mediated singlet oxygen ( 1 O 2 ), superoxide anion radicals (O 2 •- ), and hydroxyl radicals (•OH) generation, combining with the MBT-triggered colorimetric change of 3,3′,5,5′-tetramethylbenzidine (TMB), the absorbance and colorimetric methods with a broad linear detection range spanning 0.25 to 30 μM and 122 nM limit of detection are established. Furthermore, leveraging the evident ROS production by the nanozymes, DMC exhibits the advanced capability to modulate MBT levels and notably mitigate its biotoxicity oxidatively due to the ultrahigh reactive •OH from CuO nanoparticle compare with the MnO 2 . This research presents a facile and cost-effective approach for MBT detection while contributing positively to MBT management and environmental preservation efforts.
研究领域:
环境科学
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分析化学
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纳米技术
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2019
·Vol. 7
·期 9
·4699-4704
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IF 10.733
Jing-Xuan Zhang,Lin-Nan Zhou,Jing Cheng,Xia Yin,Wen-Tao Kuang,Yong-Jun Li
MnO2/C composites are widely used as cathode active materials or electrocatalysts in electrochemical power sources. Compared with a physical mixture of MnO2 and carbon materials, the growth of MnO2 on the surface of carbon can greatly improve the electrochemical performance of MnO2/C, and is usually performed at a temperature higher than 100 °C. From the viewpoint of sustainable development, the room-temperature growth of MnO2 on carbon would greatly reduce the cost and thermal pollution. Herein, at room temperature, we successfully planted MnO2 nanosheets over carbon particles, achieving MnO2/C composites through a redox reaction between MnO4− ions and carbonized zeolitic imidazolate framework-67 (ZIF-67) crystals (CZIF-67). Room-temperature growth of MnO2 may be attributed to the catalytic effect of CoII ions of Co3O4 nanoparticles formed during ZIF-67 carbonization. The resulting MnO2/CZIF-67 composites exhibit excellent catalytic performance towards the oxygen reduction reaction: the onset potential, the half-wave potential, and the electron transfer number are ∼0.88 V, ∼0.79 V and 3.6, respectively, which are close to the corresponding values of the state-of-the-art Pt/C. Also, the resulting MnO2/CZIF-67 shows better long-term durability and methanol tolerance than Pt/C, indicative of its potential applications in fuel cells and metal–air batteries.
研究领域:
材料科学
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电化学
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可持续能源
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2021
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IF 5.316
Zhiquan He,Yuhang Wang,Yan Li,Junjie Ma,Yimeng Song,Xiaoxu Wang,Fengping Wang
Two-dimensional (2D) MXene materials have significant potential applications in electrochemical energy storage. A Ti 3 C 2 T x MXene film can be used as a high-performance electrode for a flexible supercapacitor owing to its flexibility and excellent rate capability. However, Ti 3 C 2 T x is usually only used as a negative electrode material because it can be easily oxidized under positive (anodic) potential. Herein, we report a simple filtration method to fabricate a hybrid cathode by mixing a colloidal solution of 2D Ti 3 C 2 T x nanosheets and 1D MnO 2 nanobelts to form an alternating MnO 2 /Ti 3 C 2 T x stacked structure. Compared with pure Ti 3 C 2 T x , the hybrid cathode has higher electrochemical stability toward anodic oxidation. The MnO 2 /Ti 3 C 2 T x hybrid cathode delivers a high gravimetric capacitance of 315 F g −1 at 10 mV s −1 and a good rate capability of 166 F g −1 at 100 mV s −1 . The high stability of the MnO 2 /Ti 3 C 2 T x hybrid cathode is mainly attributed to the charge transfer-induced work function enlargement at the Ti 3 C 2 T x and MnO 2 heterointerface. Furthermore, a flexible asymmetric supercapacitor assembled using MnO 2 /Ti 3 C 2 T x as the cathode and alkalized Ti 3 C 2 T x as the anode delivers a high-voltage window up to 1.9 V. This work provides new insights for designing high-performance MXene-based cathode materials and devices for wearable electronics.
研究领域:
材料科学
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电化学储能
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柔性电子
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DOI
高影响因子
ACS ES&T Water
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2020
·
IF 0
Limei Dong,Yiming Li,Dafan Chen,Xiuping Chen,Dan Zhang
The hierarchically structured Fe3O4-MnO2-ZIF-8 composite was successfully synthesized and applied to activate peroxymonosulfate (PMS) for the degradation of bisphenol A (BPA) and other organic pollutants for the first time. Catalytic experiments revealed that the as-prepared Fe3O4-MnO2-ZIF-8 showed highly efficient catalytic activity and deep mineralization for BPA because of the loading of ZIF-8. When 60 mg/L BPA was degraded by the Fe3O4-MnO2-ZIF-8/PMS system, the removal efficiency of BPA reached 100% within 15 min and the TOC removal efficiency reached 80% within 9 min, values that were much higher than those of the catalysts reported recently. Fe3O4-MnO2-ZIF-8 can be separated conveniently from the aqueous phase under magnetic field control and shows better recyclability. Simultaneously, the Fe3O4-MnO2-ZIF-8/PMS system shows an excellent removal capability for other organic pollutants, such as phenol, tetracycline, p-hydroxybenzoic acid, and rhodamine B. Through radical quenching experiments and electron paramagnetic resonance tests, the mechanism of activation of PMS by Fe3O4-MnO2-ZIF-8 was investigated. ZIF-8 loaded on the surface of the Fe3O4-MnO2 composite can accept electrons generated from the Mn(II)/Mn(III)/Mn(IV) redox conjugate triplet and react with PMS to generate more •OH and SO4•–, thus significantly enhancing the catalytic performance. Additionally, on the basis of GC-MS analysis, the intermediates in the process of BPA degradation were tested and the possible degradation pathway was determined. This study indicates that Fe3O4-MnO2-ZIF-8 is a highly efficient catalytic material for PMS-based AOPs for the removal of various pollutants from water.
研究领域:
环境科学
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催化材料
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水处理技术
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DOI
SCIENCE OF THE TOTAL ENVIRONMENT
·
2020
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IF 6.551
Hao Zhou,Xiaoying Zhu,Baoliang Chen
A novel magnetic catalytic composite (MBM) was developed by compositing α-MnO 2 with a magnetic biochar containing Fe 3 O 4 . XRD and EDS confirmed the crystalline structure and the chemical composition of MBM, while the one-dimensional α-MnO 2 nanorods were observed on MBM by SEM. 4-chlorophenol as a typical toxic chlorinated organic compound was selected as the model pollutant. Even the MBM composite (MnO 2 content: 0.2 g/L) needed the same time (120 min) as the pure α-MnO 2 nanorods (0.2 g/L) to completely remove the 4-chlorophenol (10 mg/L) with overdosed peroxydisulfate (PDS), MBM indicated faster pollutant removal rate than the pure α-MnO 2 nanorods in the first 100 min. It is possible that the adsorption of 4-chlorophenol by biochar might shorten the migration pathway of the generated active species to the pollutants, resulting the boosted removal rate. MBM was stable in the neutral environment which was desirable for the efficient pollutant removal. Both the radical quenching tests and the EPR spectra identified the main active specie generated by activation of PDS through MBM was singlet oxygen possibly generated by recombination of superoxide ions from the metastable manganese intermediates at neutral pH. TOC data of the effluent ensured 63.5% of the pollutant molecules were completely mineralized after the degradation. The applied magnetic field could recover MBM easily for reuse. This work shed lights on the preparation of highly efficient and environmentally friendly catalytic composites for PDS activation in persistent pollutant removal.
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
PubMed
高影响因子
CHEMOSPHERE
·
2023
·
IF 8.8
Zhenda Liang,Zhiquan Chen,Yongtao Xu,Haiqing Wang,Li Zhou,Bing Yan
Manganese dioxide (MnO 2 ) has been recognized as one of the natural systems' most active mineral oxidants. However, when it comes to catalytic oxidation of antibiotic applications, pure MnO 2 falls short in delivering satisfactory performance. Hence, a set of Fe 3+ -doped porous MnO 2 (0.02Fe–MnO 2 , 0.1Fe–MnO 2 , and 0.14Fe–MnO 2 ) nanoparticles were synthesized here via a convenient and energy-efficient one-step reaction method. A series of experiments revealed that Fe-doping strategy enhances the properties of MnO 2 host by suppressing the crystalline structure, increasing the amount of surface oxygen defects, and modifying the Mn 3+ /Mn 4+ ratio. Specifically, the tetracycline (TC) removal efficiency of 0.14Fe–MnO 2 reaches 92% without the need for any additional co-oxidant, representing a 20% improvement over pristine MnO 2 nanoparticles . Moreover, this process shows a fast dynamic (achieving 70% of TC removal in just 5 min) and demonstrates pH-resistance, maintaining high TC removal efficiency (≥90%) over a wide pH range of 3.0–9.0. Mechanical studies reveal that the degradation of TC can be attributed to the oxidation by reactive oxygen radicals and Mn 3+ , with 1 O 2 being the primary radical involved in the reaction, accounting for 55% of TC removal. Importantly, cytotoxicity testing indicates that the biotoxicity of TC toward organisms can be effectively mitigated using 0.14Fe–MnO 2 nanomaterial . This study presents a readily applicable candidate for economically and conveniently eliminating of environmental TC pollution, thereby reducing the threat posed by TC pollution to the ecosystem.
研究领域:
环境科学
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纳米技术
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化学工程
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材料科学
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产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2021
·Vol. 9
·期 15
·9675-9684
·
IF 12.732
Fei Li,Yi-Lin Liu,Gui-Gen Wang,Dong Yan,Gui-Zhong Li,Hai-Xu Zhao,Hua-Yu Zhang,Hui-Ying Yang
With the increased development of wearable electronics, flexible zinc ion batteries (ZIBs) have attracted widespread attention owing to their low cost, superior safety, and simple fabrication process. Nevertheless, the limited active mass loading and low specific capacity remain challenges to be overcome. Herein, an effective in situ growth strategy is used to boost the mass loading and specific capacity of flexible ZIBs. We employed a mussel-derived polydopamine layer as an inductive catalyst to prompt the growth of flower-like δ-MnO2 on carbon cloth, which demonstrated strong adhesion to the surface, high mass loading, and excellent flexibility. In addition, the formed 3D conductive and supporting networks contribute to the realization of superior long cycle life, as well as a high specific capacity. As a result, the as-obtained flexible cathode can achieve a high initial discharge capacity of 1.3 mA h cm−2 at a current density of 1 mA cm−2 and a reversible capacity of 0.25 mA h cm−2 at 10 mA cm−2 for 10 000 cycles. Moreover, its reaction mechanism in ZIBs was analyzed via a series of ex situ characterization techniques, and the results suggest that the charge–discharge behavior is determined based on the Zn2+ (de-)intercalation in the δ-MnO2 interlayer. Remarkably, the as-developed flexible cathode is assembled into a flexible quasi-solid-state device, which shows excellent flexibility and can easily power one LED-based device, which has significant application prospects in wearable electronics. This work provides a novel tactic for the design of flexible batteries with high active mass loading and excellent electrochemical performance via employing polydopamine as an inductive catalyst.
研究领域:
材料科学
·
能源存储技术
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DOI
高影响因子
危险品化学品经营许可证（带存储）