CRYSTENGCOMM
·
2021
·Vol. 23
·期 43
·7602-7614
·
IF 3.545
Chao Feng,Gaoyan Xiong,Yaping Li,Qianqian Gao,Yuan Pan,Zhaoyang Fei,Yanpeng Li,Yukun Lu,Chenguang Liu,Yunqi Liu
Determining the effect of crystal facets on reaction performance is essential for designing an efficient propane oxidation catalyst. Herein, α-MnO2 nanowires with exposed (110), (211), (310) and (200) facets were proposed, and their crystal facet-dependent reactivity to propane oxidation was investigated. The resultant α-MnO2 nanowires with predominantly exposed (110) facets showed the maximum propane oxidation activity (T90 = 262.1 °C), oxidation rate, and turnover frequency (at 230 °C), and high stability during the oxidation of propane. In situ diffuse reflectance infrared Fourier transform spectroscopy revealed that the oxidation to form carboxylates is the decisive step; therefore, the production of reactive oxygen species is very important. The results from density of states computations revealed that the lowest electron energy was present in the (110) facet, which helps in the generation of reactive oxygen species and the regulation of the surface valence of Mn. The characterization and calculation results indicated that the (110) facets are conducive to forming oxygen vacancies, which allowed the activation and adsorption of O2 and propane, resulting in significantly enhanced propane oxidation activity. Apart from offering new insights about the structure–activity relationship of α-MnO2 with different facets exposed for short-chain volatile oxidation reactions, this study proposes a technique that can be used for improving other manganese-based catalyst oxidation systems.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
NANOTECHNOLOGY
·
2018
·Vol. 29
·期 19
·195603
·
IF 3.404
Sisi Dai,Bin Quan,Xiaohui Liang,Jing Lv,Zhihong Yang,Guangbin Ji,Youwei Du
Increasing efforts have recently been devoted to the artificial design and function of nanostructures for their application prospects in catalysis, drug delivery, energy storage, and microwave absorption. With the advantages of natural abundance, low cost, and environment friendliness, a one-dimensional (1D) MnO2 nanowire (MW) is the representative dielectric-loss absorber for its special morphology and crystalline structure. However, its low reflection loss (RL) value due to its thin thickness limits its wide development and application in the microwave absorption field. In this work, artificially designed MnO2@AIR@C (MCs), namely, 1D hollow carbon nanotubes filled with nano-MnO2, were designed and synthesized. It is found that the RL value of the MC is almost lower than −10 dB. Furthermore, the RL value was able to achieve −18.9 dB with an effective bandwidth (−10 dB) of 5.84 GHz at 2.25 mm. Simultaneously, the dielectric and interfacial polarization became stronger while the impedance matching was much better than in the single MWs. Hence, the rational design and fabrication of micro-architecture are essential and MC has great potential to be an outstanding microwave absorber.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2019
·
IF 3.45
Xuejie Yue,Tao Zhang,Dongya Yang,Fengxian Qiu
Flexible ceramic material, as a fundamental component of a toolset for the design of multifunctional materials, is very desirable, but a simple and effective preparation strategy is still missing. Herein, a flexible Si 3 N 4 /MnO 2 ceramic membrane was fabricated by facile vacuum filtration progress using hard Si 3 N 4 particles and soft ultralong MnO 2 nanowires as building blocks. The Si 3 N 4 particles were uniformly anchored into the porous flexible membrane, depending on the mechanical entanglement from ultralong MnO 2 nanowires, resulting in the excellent interface stability between them. Thanks to the flexibility of MnO 2 nanowires and interface stability, the as-prepared flexible membrane achieves superior flexibility including bending, folding, and twining. The flexible ceramic membrane can broaden the application range beyond the traditional ceramic use as hard structural materials. Moreover, the design strategy developed herein is applicable to other hard ceramic with similar issues.
研究领域:
材料科学
·
纳米技术
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2019
·
IF 6.393
Xue Hu,Xidong Liu,Xiaodan Zhang,Haiyan Cao,Yuming Huang
By tuning the photoluminescence of alloy Cu/Ag nanoclusters (NCs) and thiamine (VB 1 ) simultaneously through MnO 2 nanowires, we report a simple and label-free ratiometric fluorescent platform for sensitively and selectively sensing of glutathione (GSH). Ag doping of Cu NCs significantly enhances the quantum yield (QY, about 2-fold enhancement), oxidation resistance to air, storage stability (60 days versus 1 day), photostability and salt stability of the resultant Cu/Ag NCs. Impressively, MnO 2 nanowires quench the fluorescence of Cu/Ag NCs, while they enhance the fluorescence of nonfluorescent VB 1 via oxidation reaction between VB 1 and dissolved oxygen to produce oxVB 1 as a nanozyme catalyst. Upon introduction of GSH as a target, the MnO 2 nanowires are reduced to Mn 2+ and lose their quenching capacity and oxidase-like activity, resulting in FL recovery of Cu/Ag NCs and fluorescent decrease of oxVB 1 . Hence, a ratiometric luminescence signal is obtained, providing a novel ratiometric fluorescent strategy for detecting GSH through target induced regulation of the catalytic activities and quenching ability of MnO 2 nanowires. The sensor exhibited a wide linear concentration range (10 nM to 70 μM) for GSH with a detection limit of 6.5 nM. The ratiometric sensor was successfully used for GSH detection in biological samples.
研究领域:
分析化学
·
生物医学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Minjia Meng,Yi Li,Hui Peng,Binrong Li,Chuanxun Zhang,Jiajia Ren,Qingluola Ren,Yan Liu,Jianming Pan
The selective separation and purification of ART and ARE using molecularly imprinted membrane (MIM) has attracted considerable attention, but most of conventional blending MIM face low adsorption capacity and poor selectivity due to the blockage of imprinting sites. Herein, an alternative ART imprinted MnO 2 nanowires “coating” membrane (MINM) with hydrophilicity was fabricated by vacuum filtration of imprinted MnO 2 nanowires and graphene oxide nanosheets on PVDF membrane surface for selective ART separation. For the MINM, the imprinted MnO 2 nanowires coating offers more available exposed imprinting sites on the MINM surface compared to that of the blending MIM, while the introduction of graphene oxide improves the hydrophilicity of MINM, significantly reducing the non-specific absorption. Consequently, the MINM exhibits ultrahigh ART adsorption capacity and selectivity, with the ART adsorption amount of 335 mg g −1 at 5 min using dynamic cross-flow separation system, about 12.18 times higher than that of ARE (27.5 mg g −1 ), and the separation factor ( a ) value of 12.39. Moreover, the ATR FT-IR dynamic spectrum discloses the in-situ formation of H-bond between ART and MINM, playing a key role in the selective adsorption process. This work provides an alternative strategy to prepare “coating” MIM for high-efficient and selective separation of complex analogue systems.
研究领域:
材料科学
·
药物化学
·
分离技术
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS TECHNOLOGY
·
2021
·
IF 3.846
Liangshuo Li,Shuhua Pang,Xin Fan,Yanfang Wang,Hua Cheng,Dong Fang,Lin Qin,Ming Deng,Zhouguang Lu
Aqueous supercapacitor shows a narrow operating voltage range because of the limitation of the water electrolysis, resulting in low energy density. In this work, a nanoporous MnO2 entangled hierarchical porous carbon skeleton (simplified to MHPC) has been successfully prepared. Aqueous asymmetric supercapacitor has been assembled by employing the MHPC as a positive electrode, a hierarchical porous carbon skeleton (HPC) as a negative electrode, and a neutral Na2SO4 aqueous solution as electrolyte. The assembled asymmetric supercapacitor can be stably charged in an aqueous medium in a wide voltage range of 0–2.5 V and delivers a maximum energy density of 20.8Wh/kg at a power density of 0.25 kW/kg and 25 kW/kg at an energy density of 11.1 Wh/kg in a 1 M Na2SO4 aqueous solution. This strategy provides a new idea for developing high-energy supercapacitor.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
·
2022
·
IF 2.042
Dongyang Zhou,Bin Gu,Jingjing Wang,Lili Ren,Guoguang Chen,Xiaolong Yang,Zhang Tao
In order to enhance the adsorption property of adsorbent, surface modification of existing adsorption materials has always been an interesting and challenging topic. Herein, the flower-like MnO2 nanowires (MNs) with three dimensions surface area and great adsorption property was successfully prepared by two-step hydrothermal route via MnO2 nanosheets in-situ growth on MnO2 nanowires. As an adsorbent, the MNs was evaluated for the removal of methylene blue (MB) from the aqueous solution. The effect of pH value, contact time, adsorbent dose, adsorption equilibrium, kinetics adsorption process, and isothermal models was investigated. The results showed that the maximum adsorption capacity of MNs of 2 g/L attained 34.247 mg/g at 5 minutes, and kinetics of MB were found fitting using the Langmuir model and the pseudo-first-order model, respectively. Furthermore, the adsorption capacity can be kept over 90% after five adsorption cycles. Therefore, the composite material can be a promising tool for developing a large variety of efficient and stable adsorbents by combining with different nanostructures for dyeing wastewater treatment.
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
Chemosensors
·
2023
·Vol. 11
·期 9
·482
·
IF 4.2
Chunmao Zhu,Qi Wu,Fanshu Yuan,Jie Liu,Dongtian Wang,Qianli Zhang
In this paper, a MnO2nanowire (MnO2-NW) modified carbon paper electrode (CP) was developed as a novel electrochemical sensor for the sensitive determination of tetrabromobisphenol A (TBBPA). The MnO2nanowire was prepared by a hydrothermal synthesis method, and the morphology and structure of MnO2were characterized using scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The electrochemical performance of TBBPA on MnO2-NW/CP was investigated by cyclic voltammetry, and the result confirmed that MnO2-NW/CP exhibited excellent sensitivity for the determination of TBBPA due to the high specific surface area and good electrical conductivity of the nanowire-like MnO2. Moreover, the important electrochemical factors such as pH value, incubation time and modified material proportion were systematically studied to improve the determination sensitivity. The interferences from similar structure compounds on TBBPA have also been investigated. Under the optimal conditions, MnO2-NW/CP displayed a linear range of 70~500 nM for TBBPA with a detection limit of 3.1 nM. This was superior to some electrochemical methods in reference. The work presents a novel and simple method for the determination of TBBPA.
研究领域:
分析化学
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2021
·
IF 8.198
Muhammad Sultan Irshad,Xianbao Wang,Misbah Sehar Abbasi,Naila Arshad,Zihe Chen,Zhenzhen Guo,Li Yu,Jingwen Qian,Jun You,Tao Mei
Solar-driven steam generation is anticipated as one of the most promising and inventive technologies to address the primitive issues of water shortage. Although extensive attempts have been made to develop highly efficient solar steam generators, hindrances are faced to integrate all desired functions in a single evaporating system. Herein, we designed semiconductive in situ-polymerized MnO2 nanowires/chitosan (SPM-CH) hydrogels as flexible, built-in, vertically aligned, macropore-based water channels (∼0.5 μm pore size) for enhanced solar water generation (17.02 kg m–2 in 1 day). The nonradiative relaxation-dependent defect engineering of SPM-CH hydrogel promotes more lattice vibrations, and its polymeric network endorses the formation of enhanced intermediate water clusters for vapor generation. The self-floating and salt-resistant device possesses an excellent evaporation rate (1.78 kg m–2 h–1) during a single sunny day along with efficient solar energy conversion efficiency (90.6%) under 1 sun intensity, good solar absorption (94%), and good compressing flexibility (42% compressive strain). Moreover, COMSOL Multiphysics simulations of SPM-CH hydrogels under experimental conditions reveal its superior centralized heat accumulation within the top-interface matrix. The single-step execution for a freshwater supply purified from various contaminations including industrial wastewater and oil-emulsified water shows its potential as a reusable device toward real-life applications.
研究领域:
材料科学
·
能源技术
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Lidong Sun,Nian Li,Shudong Zhang,Xinling Yu,Cui Liu,Yongqiang Zhou,Shuai Han,Wenbo Wang,Zhenyang Wang
Porous carbon composite electrodes have attracted extensive attention due to their excellent electrochemical performance toward energy storage applications. In this work, hierarchical nitrogen-containing porous carbon (HNPC) and α-MnO 2 nanowires composite electrode is prepared through a template method. The as-prepared composite electrode, characterized as one-dimensional nanowires inserted into three-dimensional interconnected porous structures, exhibits high specific capacitance of 204.6 F g −1 at 1 A g −1 and excellent cycling stability (97.2% remains after 5000 cycles). Moreover, the fabricated asymmetric supercapacitor based on HNPC//HNPC/MnO 2 achieves a wide working voltage window of 1.8 V and a high energy density up to 30.1 Wh kg −1 at a power density of 900.0 W kg −1 . The results indicate that the HNPC/MnO 2 composite electrodes with excellent electrochemical performance have promising perspective in supercapacitor applications.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Physics
·
2022
·
IF 11.021
Yue Liu,Zirui Jia,Jixi Zhou,Guanglei Wu
One-dimensional (1D) nanomaterials allow reflection of electromagnetic (EM) waves due to large anisotropy and aspect ratio. It is still a challenge to optimize the impedance matching characteristic for strong EM dissipation of 1D nanomaterials. Herein, we propose a strategy of incorporating two-dimensional (2D) layered double hydroxides (LDHs) sheets with 1D nanowires to reinforce interactions with EM waves. Wherein, 1D MnO 2 nanowires are used to support the LDH nanosheets , which facilitates the EM waves capture and impedance matching characteristics. Moreover, the heterogeneous interfaces and vacancies contributes to the polarization loss as well. As a consequence, the minimum reflection loss ( RL min ) of MnO 2 @ZnCoNi-LDHs demonstrates −56.3 dB at 2.4 mm and the broad effective absorption bandwidth ( f E ) reaches 4.56 GHz at 2.1 mm. This heterogeneous structure assembly strategy can be served as a reference for refining the absorption performance of 1D EM absorbers.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2021
·
IF 3.764
Yongfang Chen,Bin Gu,Yuqi Li,Dongya Yang,Fengxian Qiu,Tao Zhang
Controllable and reliable fabrication of wearable materials with tunable structures and integrated functionalities is urgently required for personal thermal management. Here, MnO2 nanowires@Ag/cellulose laminated membranes with infrared insulation, antibacterial, and unidirectional liquid penetration properties assembled were fabricated by hydrophobic cellulose, hydrophilic cellulose, and ultralong MnO2 nanowires@Ag in vacuum filtration and magnetron sputtering methods. The results indicated that nanosilver coating with high infrared radiation reflectivity and excellent electrical conductivity was successfully fabricated onto MnO2 nanowire surfaces, resulting in infrared insulation properties of the laminated cellulose membranes. In addition, the laminated membranes exhibit unidirectional liquid penetration properties that can enhance the wearing comfort. In antibacterial tests against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, the high antibacterial activity is revealed. These results indicate the promising potential of the laminated cellulose membranes for tackling personal thermal management issues related to wearable applications.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
DOI
高影响因子
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