Journal of Nanomaterials
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2014
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IF 1.611
Jiancheng Wang,Zhaoliang Peng,Bing Wang,Lina Han,Liping Chang,Weiren Bao,Gang Feng
A series of manganese salts (Mn(NO3)2, MnCl2, MnSO4, and Mn(Ac)2) and silicon materials (silica sand, silica sol, and tetraethyl orthosilicate) were used to synthesize Mn/Si complexes in supercritical water using a tube reactor. X-ray diffraction (XRD), X-ray photoelectron spectrometer (XPS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) were employed to characterize the structure and morphology of the solid products. It was found that MnO2, Mn2O3, and Mn2SiO4 could be obtained in supercritical water at 673 K in 5 minutes. The roles of both anions of manganese salts and silicon species in the formation of manganese silicon complexes were discussed. The inorganic manganese salt with the oxyacid radical could be easily decomposed to produce MnO2/SiO2 and Mn2O3/SiO2. It is interesting to found that Mn(Ac)2 can react with various types of silicon to produce Mn2SiO4. The hydroxyl groups of the SiO2 surface from different silicon sources enhance the reactivity of SiO2.
研究领域:
化学
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材料科学
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DOI
高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
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2019
·Vol. 321
·期 2
·671-681
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IF 1.186
Xiu Taoyuan,Liu Zhirong,Yang Lingfang,Wang Yun
The hydrated manganese dioxide (HMO) was synthesized by hydrothermal process using MnSO 4 and KMnO 4 . The adsorption of HMO for Th(IV) and U(VI) were investigated by batch static adsorption experiments. The HMO and MnO 2 were characterized by FT-IR, XRD and SEM. At the same time, the adsorption mechanism is discussed. The adsorption process was in line with the pseudo-second-order kinetic model and Langmuir isothermal model. The maximum adsorption capacities were Th ( T = 308 K, C 0 = 200 mg L −1 , q max = 218.34 mg g −1 ) and U ( T = 308 K, C 0 = 200 mg L −1 , q max = 55.19 mg g −1 ).
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
MICROCHEMICAL JOURNAL
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2020
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IF 3.594
Yong Li,Xuan Li,Hongliang Tan,Zhen-Zheng Huang
In this work, a turn-on fluorescent assay based on carbon dots/manganese dioxide nanosheet (CDs/MnO 2 ) assembly was developed for the detection of glucose. The fluorescence of CDs was first quenched by the addition of MnO 2 nanosheet to form CDs/MnO 2 assembly, which leads to a fluorescence resonance energy transfer (FRET) process from CDs to MnO 2 nanosheet. When H 2 O 2 was introduced into the quenched CDs solution, the MnO 2 nanosheet was destroyed due to the redox reaction between H 2 O 2 and MnO 2 nanosheet, and the fluorescence of CDs was recovered accordingly. On this basis, by coupling with the oxidation reaction of glucose catalyzed by glucose oxidase, which produces gluconic acid and H 2 O 2 , a fluorescent assay for the quantitative analysis of glucose can be proposed. Under optimal conditions, the fluorescent intensity of CDs increased linearly with increasing concentrations of glucose from 2 to 200 μM, and the detection limit towards glucose was calculated to be 0.83 μM. In addition, the proposed fluorescent assay was successfully applied to the determination of glucose in serum samples with satisfactory results. This proposed fluorescent assay is simple, cost-effective and environmentally friendly, and thereby holding great potential for diabetes management and biosensing applications.
研究领域:
生物化学
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医学诊断
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DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
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2019
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IF 9.518
Ying Gan,Ning Hu,Chuanjiang He,Shuqi Zhou,Jiawei Tu,Tao Liang,Yuxiang Pan,Dmitry Kirsanov,Andrey Legin,Hao Wan,Ping Wang
Urolithiasis commonly occurs in kidney and ureteral, and may cause local organ/tissue damage, even kidney failure. The incidence of this disease is increasing worldwide, in which calcium oxalate is the major composition forming the urinary calculus. Therefore, to monitor this disease for the prevention and treatment, measuring the oxalate in the urine is of great significance. Here, a rapid and sensitive colorimetric method was developed based on 3,3',5,5'-tetramethylbenzidine-manganese dioxide (TMB-MnO 2 ) nanosheets for oxalate detection. MnO 2 nanosheets acted as an efficient biomimetic oxidase to catalyze the reaction with TMB and oxalate. Pale yellow TMB can be oxidized to blue oxide TMB catalyzed by BSA-stabilized MnO 2 nanosheets, and oxalate can selectively inhibit this reaction by consuming and reacting with MnO 2 nanosheets, thus achieving the quantitative detection of oxalate. Moreover, a home-made bionic electronic-eye (E-eye) system was developed as a portable in-situ detection platform to efficiently measure the oxalate concentrations in 10 s by direct photographing. By optimizing experimental conditions, this method shows a wide linear range (7.8 μM to 250 μM) and a low detection limit (0.91 μM) for oxalate detection. Besides, this method exhibits high selectivity even with 80-fold interfering chemicals. Furthermore, the performance of the method was validated by testing the artificial urine samples, indicating its great potential for monitoring and diagnosis of urolithiasis in point-of-care applications.
研究领域:
生物化学
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分析化学
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医学诊断
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Guoguang Chen,Shiyu Yan,Chengcheng Ouyang,Lirong Qiu,Jia Liu,Lili Ren
Manganese dioxide (MnO 2 ) nanocrystal, a kind of nanomaterial with excellent enzyme-like catalytic properties, have been widely used in chemical, biological and pharmaceutical fields. It is composed of unique octahedral units that form a variety of tunnels and layered structures, which also lead to the emergence of different crystal forms and properties. In this study, different crystalline types of MnO 2 were synthesized by different methods, and different substrates were used to study MnO 2 catalytic ability of H 2 O 2 . β- MnO 2 nanocrystal had nearly 50% oxygen, among which adsorbed oxygen accounted for nearly 65%, so it exhibited the best catalytic performance and could promote oxidation catalytic reaction well. Furthermore, a functional MnO 2 hydrogel was prepared using β-MnO 2 as antibacterial agent and natural gelatin hydrogel as carrier. The antibacterial performance of the new hydrogel was further studied, and the survival rate of different species of bacteria was<5% after high concentration of MnO 2 functional hydrogel. In the end, MnO 2 functional hydrogel was applied to the wound treatment of mice infected with antibiotic resistant bacteria, and it was found that the wound healing rate of mice was nearly 100% on the 14th day, indicating that it had the potential of a new antibacterial dressing.
研究领域:
材料科学
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生物医学工程
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药学
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伤口护理
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DOI
高影响因子
Journal of Energy Storage
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2023
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IF 9.4
Weitao Shi,Feifan Hong,Renhuan Li,Ruolin Zhao,Sizhi Ding,Ziqi Liu,Peilin Qing,Yi Fan,Haizhen Liu,Jin Guo,Zhiqiang Lan
MgH 2 is a promising high-capacity solid hydrogen storage material. In this work, MnO 2 -doped Ti 3 C 2 (Ti 3 C 2 @MnO 2 ) was synthesized and used as a catalyst to improve the hydrogen storage performance of MgH 2 . We found that the dehydrogenated 10 wt% Ti 3 C 2 @MnO 2 -doped MgH 2 sample exhibited good hydrogen adsorption ability even at room temperature (30 °C), and could absorb 5.13 wt% of hydrogen in 400 s at 75 °C. The re‑hydrogenated Ti 3 C 2 @MnO 2 -doped MgH 2 sample started to release hydrogen at 182 °C and required 484 s to completely release hydrogen at 275 °C with a dehydrogenation capacity of 6.4 wt%. The Ti 3 C 2 @MnO 2 composite did not change the thermodynamic properties of MgH 2 . In the MgH 2 + Ti 3 C 2 @MnO 2 sample, Ti 3 C 2 , TiO 2 , MnO 2 , MnO, and Mn combined with MgH 2 to form Ti 3 C 2 /MgH 2 , TiO 2 /MgH 2 , MnO 2 /MgH 2 , MnO/MgH 2 , and Mn/MgH 2 multiphase interfaces, which improved the hydrogen storage performance of MgH 2 . The findings of this work may provide a new strategy for preparing novel and efficient catalysts for hydrogen storage applications.
研究领域:
材料科学
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能源存储
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DOI
高影响因子
Catalysts
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2019
·Vol. 9
·期 11
·911
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IF 3.444
Tianming Liu,Guobao Yuan,Guocheng Lv,Yuxin Li,Libing Liao,Siyao Qiu,Chenghua Sun
Microwave-induced catalytic degradation (MICD) has been considered as one of the most prospective approaches to remove organic contaminants from water. High-performance catalysts, ideally offering efficient degradation ability, are essential to this process. This work reports the fabrication of manganese oxide on carbon nanotubes (MnO/CNTs) as an efficient catalyst under microwave irradiation (MI) to remove tetracycline (TC) from aqueous solution. The hybrid MnO/CNTs structure shows excellent performance in TC degradation. Combining experimental characterization and theoretical calculations, synergistic mechanisms are revealed: (i) Strong MnO/CNTs interaction stabilizes Mn(II) through interfacial bonding; (ii) high-spin states associated with low coordinated Mn(II) play a major role in MICD; and (iii) superoxide radicals (•O2−) and hydroxyl radicals (•OH) induced by microwave input are identified as the major active species.Keywords:microwave-induced;manganese oxide;catalysts;tetracycline;degradation
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
Nanomaterials
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2023
·Vol. 13
·期 4
·775
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IF 5.3
Hong Su,Jiangping Liu,Yanan Hu,Tianhao Ai,Chenhao Gong,Jichang Lu,Yongming Luo
As a representative sulfur-containing volatile organic compounds (S-VOCs), CH3SH has attracted widespread attention due to its adverse environmental and health risks. The performance of Mn-based catalysts and the effect of their crystal structure on the CH3SH catalytic reaction have yet to be systematically investigated. In this paper, two different crystalline phases of tunneled MnO2(α-MnO2and β-MnO2) with the similar nanorod morphology were used to remove CH3SH, and their physicochemical properties were comprehensively studied using high-resolution transmission electron microscope (HRTEM) and electron paramagnetic resonance (EPR), H2-TPR, O2-TPD, Raman, and X-ray photoelectron spectroscopy (XPS) analysis. For the first time, we report that the specific reaction rate for α-MnO2(0.029 mol g−1h−1) was approximately 4.1 times higher than that of β-MnO2(0.007 mol g−1h−1). The as-synthesized α-MnO2exhibited higher CH3SH catalytic activity towards CH3SH than that of β-MnO2, which can be ascribed to the additional oxygen vacancies, stronger surface oxygen migration ability, and better redox properties from α-MnO2. The oxygen vacancies on the catalyst surface provided the main active sites for the chemisorption of CH3SH, and the subsequent electron transfer led to the decomposition of CH3SH. The lattice oxygen on catalysts could be released during the reaction and thus participated in the further oxidation of sulfur-containing species. CH3SSCH3, S0, SO32−, and SO42−were identified as the main products of CH3SH conversion. This work offers a new understanding of the interface interaction mechanism between Mn-based catalysts and S-VOCs.Keywords:CH3SH decomposition;MnO2;oxygen vacancies;oxygen migration
研究领域:
催化化学
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环境科学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Shining Niu,Qian Chen,Lulu Yu,Xiao Wang,Haipeng Yu,Mei Wen,Zhigang Chen,Nuo Yu,Kun Li
Natural bacteria and bacterial bionics offer significant advantages in the synergistic approach to cancer treatments, while the development of such platforms remains challenging. Herein, bacterial membrane-coated chlorin e6-conjugated bacteriform manganese dioxide platform (BCBM) has been developed for amplifying phototherapeutic efficacy of tumors. The BCBM platform has been prepared by the in-situ growth of manganese dioxide on the surface of silica nanorods and subsequent etching process, photosensitizer conjugation, and bacterial membrane encapsulation. The manganese dioxide and bacterial membrane endow the BCBM with bacteria-like characteristics, enabling a specific response to the tumor microenvironment (TME). The manganese dioxide can react with hydrogen peroxide to produce large amounts of oxygen and manganese ions under acidic conditions. Upon near-infrared irradiation, the BCBM exhibits an excellent ability to generate reactive oxygen species because of sufficient oxygen supply. Furthermore, the released manganese ions activate cGAS-STING pathway, leading to the efficient apoptosis of cancer cells. The process of apoptosis is accompanied by the release of tumor-associated signaling molecules, which enhances therapeutic efficacy. Therefore, this work offers insights into designing biomimetic multifunctional nanoagents against cancers.
研究领域:
肿瘤学
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生物材料
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免疫治疗
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纳米医学
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产品关联
DOI
高影响因子
FUEL
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2024
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IF 6.7
Yang Liu,Shaokai Ma,Shiqing Zhang,Fang Liu,Ying Wang,Xinyu Sun,Ying Li,Yanming Xue,Chengchun Tang,Jun Zhang
Efficient and sustainable hydrogen production via water electrolysis relies on the utilization of highly active electrocatalysts for the oxygen evolution reaction (OER). Birnessite (δ-MnO 2 ), a type of manganese oxide with a local atomic structure similar to the oxygen-evolving complex in photosystem II, has emerged as a highly promising OER catalyst. Despite considerable efforts have been dedicated to enhancing its activity, the crucial aspect of stability has been often overlooked. Herein, Ti ions have been selectively incorporated into the in-layered lattice of δ-MnO 2 nanosheet arrays using a hydrothermal method, aiming to enhance the stability without reducing its activity. The resulting optimal Ti-MnO 2 catalyst demonstrates enhanced OER activity in alkaline electrolyte, exhibiting an impressive 85 mV reduction in overpotential at 10 mA cm −2 , surpassing the initial MnO 2 (495 mV reduced to 410 mV). Remarkably, it shows exceptional durability, with negligible performance decrease observed over the entire 50-hour testing period. It has been demonstrated that the incorporation of Ti serves a dual purpose: it adjusts the electronic structure around Mn, enhancing activity, and simultaneously stabilizes the Mn 3+ active sites, resulting in exceptional durability. Furthermore, density functional theory (DFT) calculations provide additional confirmation of the optimized electronic structure of MnO 2 achieved through Ti doping, leading to a reduction in the free energy of adsorbed intermediates and expediting the kinetics of the OER process. Our findings open a pathway for enhancing OER stability and activity by doping electrocatalytic inert ions into the lattice of MnO 2 , applicable not only to Mn-based oxides but also other non-precious metal-based electrocatalysts.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
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2024
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IF 6.7
Bodong Wang,Shan Pu,Bingxin Ma,Xingyan Zou,Qing Xiong,Xiandeng Hou,Kailai Xu
Hydride generation-based optical sensors have achieved on-site visual selenium (Se) determination with high anti-interference capability, yet they rely on the change of single-color intensity with a narrow linear dynamic range. Herein, we combined selenium hydride (H2Se)-induced activity inhibition of a manganese dioxide (MnO2) nanozyme with different degrees of 3,3′,5,5′-tetramethylbenzidine (TMB) oxidation to realize sensitive multicolor visual detection of Se(IV). Due to its high oxidase-like (OXD-like) activity and sensitive response to H2Se, amorphous/crystalline manganese dioxide (ac-MnO2) was selected to form the headspace single droplet for microextraction and recognition. Via headspace redox reaction with H2Se, ac-MnO2 was reduced into low valence accompanied by in situ generation of Se nanoparticles, leading to the formation of a Se-MnOx aggregate. The experimental results and theoretical calculation indicated that, compared with MnO2, Se-MnOx had decreased active sites for adsorbing O2 to generate •O2–, resulting in the nanozyme activity inhibition that was totally dependent on Se(IV) concentration. The implementation of this strategy enabled accurate Se(IV) detection with a linear range from 10 to 600 μg L–1 and a limit of detection of 1.8 μg L–1. The portable smartphone-based detection for real sample analysis further demonstrated that this assay can be an easy, convenient, and intelligent tool for on-site selenium determination.
研究领域:
分析化学
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环境科学
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生物医学工程
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2021
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IF 5.816
Mengwei Guo,Zhuoming Wei,Qibo Zhang
The rational design and synthesis of highly efficient, precious metal-free electrocatalysts in the promotion of electrochemical water oxidation is essential for the sustainable use of renewable energy. Herein, an integrated, S-doped MnO x /Mn film developed on carbon paper (CP) formed by a two-step transformation approach that includes template-free electrodeposition and in-situ electrochemical oxidation is employed as an efficient oxygen evolution reaction (OER) electrocatalyst. The doping of S and in-situ electro-oxidation lead to a tailored electronic structure and phase composition , which endow the composite electrode with a significantly enhanced OER catalytic performance. This S-doped integrated electrode perfectly combines highly active MnO x outer layers with conductive metallic Mn inner layers to offer abundant catalytic interfaces and electronic paths, leading to favorable reaction kinetics. As a result, the optimal S-doped MnO x /Mn/CP offers a low overpotential of 435 mV at 10 mA cm −2 with a Tafel slope of 89.97 mV dec −1 as well as improved stability. Impressively, a highly intrinsic catalytic activity with a turnover frequency of 0.0112 s −1 is obtained for S-doped MnO x /Mn/CP, which is 4.2-fold higher than that of MnO x /Mn/CP. S doping plays a critical role in stabilizing the Mn III O x active phase and is ultimately responsible for the enhanced catalytic performance. This work provides an integrated design concept and S doping approach suitable for boosting the OER catalytic performance of MnO x .
研究领域:
材料科学
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电化学
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DOI
高影响因子
危险品化学品经营许可证（带存储）