JOURNAL OF ALLOYS AND COMPOUNDS
·
2016
·
IF 3.014
Huajun Sun,Saihong Duan,Xiaofang Liu,Dawei Wang,Huiting Sui
Lead-free Ba 0.98 Ca 0.02 Zr 0.02 Ti 0.98 O 3 -xmol% MnO 2 (BCZT-xMn) (x = 0.1, 0.2, 0.3, 0.4, 0.5) ceramics were prepared by conventional solid-state reaction method and the effects of MnO 2 doping content and sintering temperature on microstructure and electrical properties of BCZT ceramics were studied. The ceramics samples with all MnO 2 doping contents exhibit pure perovskite structure and similar Curie temperature of approximately 120 °C. Among all, the sample with 0.3 mol. % MnO 2 doping content sintered at 1400 °C exhibits improved ferroelectricity with a relatively high remnant polarization ( P r ) and low coercive electric field ( E c ) of 15.7 μC/cm 2 and 180 V/mm, respectively, which can be attributed to the fact that an appropriate doping content of MnO 2 does favor to the grain growth, with the favorable effect on domain motion. Accordingly, excellent piezoelectric property with piezoelectric coefficient ( d 33 ) of 308 pC/N can be obtained. Besides, the sample shows a relatively low dielectric loss (tanδ) of 1.04%. As a result, the BCZT-xMn ceramic exhibits the potential to be used in memory and transformer applications.
研究领域:
材料科学
·
电子工程
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DOI
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2016
·Vol. 34
·期 8
·839-846
·
IF 1.872
Zheng Liu,Weiliang Chen,Xin Fan,Jianyang Yu,Yu Zhao
MnO 2 /polyaniline/graphene composite as a supercapacitor electrode material was synthesized through an interfacial polymerization approach in the interface of oil/water phase. The as-synthesized MPG is characterized by infrared spectroscopy, XRD, XPS, SEM and TEM, and its electrochemical performance is measured by cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy. The 3D nanostructure of MPG and loose nanorod structure of polyaniline (PANI) coated with round MnO 2 pellets could be clearly observed. The maximum energy density of MPG is 45.4 Wh/kg (at a power density of 67.8 kW/kg) and the highest power density is 229.2 kW/kg (at an energy density of 25.7 Wh/kg). The capacitance retentions after 500 cycles at the scan rate of 5 mV/s for MGP composite and PANI/graphene are 70.4% and 59.1%, respectively, and the capacitance values after 500 cycles are 158.4 F/g and 114.8 F/g, respectively. The improved performance of MPG is due to the 3D nanostructure, loose nanorod structure of PANI and stable support of graphene, which prevent the mechanical deformation effectively during the fast charge/discharge process and facilitate the diffusion of the electrolyte ions into the inner region of active materials. The composite material is very promising for the next generation of high-performance supercapacitors electrode.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2021
·Vol. 27
·期 1
·135
·
IF 4.412
Zhengwei Qu,Yi Wang,Pingan Yang,Wei Zheng,Nan Li,Jingying Bai,Youwei Zhang,Kailin Li,Dashuang Wang,Zhaohui Liu,Kexin Yao,Rui Li,Yuxin Zhang
In this work, spherical flower-shaped composite carbonyl iron powder@MnO2(CIP@MnO2) with CIP as the core and ultrathin MnO2nanosheets as the shell was successfully prepared by a simple redox reaction to improve oxidation resistance and electromagnetic wave absorption properties. The microwave-absorbing properties of CIP@MnO2composites with different filling ratios (mass fractions of 20%, 40%, and 60% after mixing with paraffin) were tested and analyzed. The experimental results show that compared with pure CIP, the CIP@MnO2composites have smaller minimum reflection loss and a wider effective absorption bandwidth than CIP (RL < −20 dB). The sample filled with 40 wt% has the best comprehensive performance, the minimum reflection loss is −63.87 dB at 6.32 GHz, and the effective absorption bandwidth (RL < −20 dB) reaches 7.28 GHz in the range of 5.92 GHz–9.28 GHz and 11.2 GHz–15.12 GHz, which covers most C and X bands. Such excellent microwave absorption performance of the spherical flower-like CIP@MnO2composites is attributed to the combined effect of multiple beneficial components and the electromagnetic attenuation ability generated by the special spherical flower-like structure. Furthermore, this spherical flower-like core–shell shape aids in the creation of discontinuous networks, which improve microwave incidence dispersion, polarize more interfacial charges, and allow electromagnetic wave absorption. In theory, this research could lead to a simple and efficient process for producing spherical flower-shaped CIP@MnO2composites with high absorption, a wide band, and oxidation resistance for a wide range of applications.Keywords:spherical flower-like structure;CIP@MnO2;microwave absorption;interfacial polarization
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LUMINESCENCE
·
2020
·Vol. 35
·期 6
·897-902
·
IF 1.855
Keke Ning,Guoqiang Xiang,Cuicui Wang,Feihong Huang,Jinzhi Liu,Lanlan Zhang,Minmin Yan,Bingqian Hu,Wen Lei
A ‘turn-on’ fluorescence method for detection of hydrogen peroxide (H 2 O 2 ) in marine food samples is presented in this article. Using this method, a carbon dots (CDs)–MnO 2 probe was formed in which fluorescence intensity (FI) of CDs was quenched through fluorescence resonance energy transfer by addition of MnO 2 nanosheets. When H 2 O 2 was added into the CDs–MnO 2 solution, the MnO 2 nanosheets formed Mn 2+ ions due to a redox reaction between H 2 O 2 and MnO 2 nanosheets, and CD FI was recovered. Under optimized conditions, the detection limit for H 2 O 2 was 0.87 μM, and analytical linear range was 4–100 μM. Furthermore, this developed fluorescence sensing system was successfully used with satisfactory results to determine trace H 2 O 2 content in marine food samples.
研究领域:
分析化学
·
食品科学
·
海洋生物学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Hao Chen,Jingdong Guo,Shandong Tan,Xueqi Zhang,Zhiyuan Sang,De'an Yang
MnO 2 has outstanding potential for application in cathode materials of zinc ion batteries (ZIBs). However, the poor electrical conductivity , poor ion diffusion kinetics, and structural instability greatly limit its rate performance, specific capacity, and cycling stability. Herein, we prepared PEDOT-coated MnO 2 cathode material with oxygen vacancy defects, namely Vö-MnO 2 @PEDOT, by Dual-modification of MnO 2 nanowires. The PEDOT coating optimizes the electron transfer capability of the material while inhibiting the dissolution of MnO 2 . The oxygen vacancies accelerate ion diffusion. Vö-MnO 2 @PEDOT possesses a joint energy storage mechanism, containing the insertion/extraction of H + /Zn 2+ and dissolution/precipitation of MnO 2 . This joint energy storage mechanism explains the high specific capacity and the increase in capacity. The Vö-MnO 2 @PEDOT displays a high specific capacity of 400 mAh/g at 0.2 A/g. Besides, at 2 A/g, Vö-MnO 2 @PEDOT outputs a high capacity of 213 mAh/g after 2000 cycles. This research provides a feasible research idea for the performance optimization of manganese oxide cathode materials.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Hongdong Liu,Zhongli Hu,Yongyao Su,Rong Hu,Liangliang Tian,Lei Zhang,Haibo Ruan
Manganese dioxide (MnO 2 ) has been studied as an anode material for Li-ion batteries beyond its high theoretical specific capacity and low-cost. In this work, the 1D α-MnO 2 nanomaterials with different morphology were synthesized via a facile and green hydrothermal method. These materials are carefully investigated by XRD, Raman, SEM and BET techniques. The results show that the solution acidity strongly influenced the morphology and the specific surface area of the sample. The electrochemical behaviors of MnO 2 sample were systematically investigated by cyclic voltammetry and galvanostatic charge-discharge. As anode materials for Li-ion batteries, both of 1.2-MnO 2 and 3.6-MnO 2 deliver high initial discharge capacity and relatively excellent cycle performance, indicating that 1D α-MnO 2 is a promising anode material for high-performance lithium ion batteries.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2019
·
IF 5.383
Qi Chen,Wenjing Wei,Jingjing Tang,Jinkun Lin,Songjun Li,Maiyong Zhu
Yolk@shell nanocomposites with delicate composition and tailored structure usually exhibit great potential in various areas. In the present study, the synthesis of yolk@shell Fe 3 O 4 @MnO 2 microspheres was reported using core@shell Fe 3 O 4 @polydopamine (Fe 3 O 4 @PDA) as starting materials. This novel approach is based on the reductive property of the PDA derived carbon shell. The new shell of MnO 2 was synthesized by reaction of PDA derived carbon and KMnO 4 . The Fe 3 O 4 @MnO 2 yolk@shell microsphere was successfully used as electrode material for supercapacitor and delivers a high specific capacitance of 715 F/g at 1 A/g with a good rate capability (450 F/g at 10 A/g). Furthermore, the Fe 3 O 4 @MnO 2 yolk@shell microsphere was also used as the positive electrode for asymmetric supercapacitors (ASC), wherein N doped carbon from PDA was applied as negative electrode. As a result, the energy density of the constructed ASC device was up to 31.3 Wh/kg at a power density of 750 W/kg. Meanwhile, the Fe 3 O 4 @MnO 2 //N-pC (PDA derived N-doped porous carbon) device offers an excellent cycling stability (94.7% of capacitance retention after 5000 cycles). Such distinguish capacitive performance is undoubtedly related to the electrochemical actuation of the yolk@shell microsphere structure and their structural integrity, where the void between the shell and yolk may relieve the volume change of the electrode. Considering the efficiency and simplicity of the synthetic procedure, it is expected that the present method might be suitable for preparation of yolk@shell composite with other components and structures, offering potential in various applications.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2020
·
IF 3.99
Hua Qin,Tengfei Wu,Chuan Du,Li Ren,Lei Chen,Ding Weng,Jiadao Wang
Through a simple self-assembly method, the as-synthesized NaY/MnO 2 nanocomposites were uniformly distributed and immobilized on textile fibers, which make the nanocomposite suit for indoor formaldehyde (HCHO) removal. Compared with NaY-based textiles and MnO 2 -based textiles, the NaY/MnO 2 -based textiles using polyester (PET) as substrate exhibited superior HCHO removal activity and better stability at room temperature. Furthermore, for low-level indoor environment, HCHO removal efficiency of NaY/MnO 2 -based textiles was up to 90 % even after 30 cycles tests under the conditions of original HCHO concentration of 1 ppm. Therefore, the NaY/MnO 2 -based textiles highlighted new avenues to the practical use for low-level indoor HCHO removal.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Lina Wu,Xinjie Wang,Xiangchuan Wu,Shiqi Xu,Ming Liu,Xizhong Cao,Taishan Tang,Xingxu Huang,He Huang
The CRISPR-Cas system was developed into a molecular diagnostic tool with high sensitivity, low cost, and high specificity in recent years. Colorimetric assays based on nanozymes offer an attractive point-of-care testing method for their low cost of use and user-friendly operation. Here, a MnO2 nanozyme-mediated CRISPR-Cas12a system was instituted to detect SARS-CoV-2. MnO2 nanorods linked to magnetic beads via a single-stranded DNA (ssDNA) linker used as an oxidase-like nanozyme inducing the color change of 3,3′,5,5′-tetramethylbenzidine, which can be distinguished by the naked eye. The detection buffer color will change when the Cas12a is activated by SARS-CoV-2 and indiscriminately cleave the linker ssDNA. The detection limit was 10 copies per microliter and showed no cross-reaction with other coronaviruses. The nanozyme-mediated CRISPR-Cas12a system shows high selectivity and facile operation, with great potential for molecular diagnosis in point-of-care testing applications.
研究领域:
生物技术
·
分子生物学
·
病毒学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
·
2022
·
IF 3.428
Haiyan Lan,Linyu Wang,Suwu Liu,Yong Qian,Tianxiang Jin,LiMin Lu
Herein, MnO 2 nanosheets with good catalytic performance and MWCNTs-NH 2 with good conductivity were combined to form MnO 2 /MWCNTs-NH 2 composite with synergistic conductivity and catalytic performance. Subsequently, a novel PAR electrochemical sensor was constructed based on MnO 2 /MWCNTs-NH 2 composite. Some important conditions such as enrichment time, pH value of PBS and modification volume of MnO 2 /MWCNTs-NH 2 were optimized to obtain the best detection performance for PAR. The synergistic catalytic effect of MWCNTs-NH 2 and MnO 2 endowed the composite with good catalytic performance toward the oxidation of PAR. The sensor presented a wide linear range from 0.001 to 20 μM and a low detection limit of 1 nM. Additionally, the sensor exhibited satisfactory reproducibility, repeatability, stability, selectivity, and was successfully applied for the detection of PAR in urine samples.
研究领域:
分析化学
·
材料科学
·
药物分析
✓ 已验证
DOI
高影响因子
SENSORS
·
2018
·Vol. 18
·期 8
·2525
·
IF 2.475
Zhengjun Huang,Linlin Zheng,Feng Feng,Yuyuan Chen,Zhenzhen Wang,Zhen Lin,Xinhua Lin,Shaohuang Weng
Simple and effective methods for the detection of the level of blood glucose are closely linked to the monitoring of people’s health. In the study, MnO2nanosheets with absorption range of 300 nm~500 nm and obvious yellow color were easily prepared and applied to detect glucose through their absorbance and color. The proposed method is based on the fact that a specific concentration of glucose can be quantitatively transformed into hydrogen peroxide (H2O2) under the catalytic effect of glucose oxidase. Based on the redox reaction of MnO2with H2O2, yellow MnO2can be converted into colorless Mn2+to monitor the concentration of glucose. Under optimal conditions, a simple and effective visual assay for the sensitive and reliable detection of glucose was developed. The linear range was estimated to the range from 0 μM to 100 μM, with a detection limit of 12.8 μM. Furthermore, the proposed colorimetric assay based on MnO2nanosheets can effectively detect blood glucose of clinical serum samples with accuracy and convenience.Keywords:glucose;colorimetric assay;MnO2nanosheets;UV-vis;quantitative determination
研究领域:
生物化学
·
医学检测
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Xinying Ding,Yuanbin Wen,Chen Qing,Yaru Wei,Pengcheng Wang,Jingyi Liu,Zhanhong Peng,Yihui Song,Houyang Chen,Qian Rong
δ-MnO 2 was proposed as a promising cathode material for aqueous Zn-ion batteries. Nonetheless, its potential application has been impeded by its unstable crystal structure and sluggish reaction kinetics with Zn ions. Herein, we utilized Cr to modify δ-MnO 2 by a simple hydrothermal method to develop cathode materials for aqueous Zn-ion batteries with better stability and electron transport properties. The introduction of Cr enhanced the specific capacity and cycling stability of δ-MnO 2 , in particular, the 3% Cr doped δ-MnO 2 electrode exhibited a large specific capacity of 229.2 mAh·g −1 at 0.1 A·g −1 and an excellent capacitance retention of 86.0% after performing 300 cycles. The density functional theory (DFT) calculations indicate that the introduction of Cr decreases the band gap of MnO 2 and enhances electron migration in the electrode material. Meanwhile, the introduction of Cr substantially improved the Zn ion adsorption and enhanced the binding energy of δ-MnO 2 , indicating that the addition of Cr promoted the interaction between the Cr doping δ-MnO 2 (Cr-MnO 2 ) electrode materials with Zn ions, while making the structure of the electrode materials more stable. As a result, this suppresses the Jahn-Teller distortion and reduces the solvation and phase transition of Mn.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）