JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2017
·
IF 3.012
Aijuan Xie,Feng Tao,Chao Jiang,Wenliang Sun,Yanfang Li,Lina Hu,Xiang Du,Shiping Luo,Chao Yao
The different crystallographic structures of manganese dioxide (α-MnO 2 , β-MnO 2 , γ-MnO 2 and δ-MnO 2 ) were prepared via simple and feasible methods. Among four crystallographic structures, γ-MnO 2 exhibited the best electrochemical property and was chosen to compound γ-MnO 2 /polyaniline (PANI) composite electrode through in situ synthesis techniques. The as-prepared samples were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD). The electrochemical properties of as-prepared samples influenced by the different mass ratios, scan rates, and current densities were mainly investigated by cyclic voltammetry (CV), galvanostatic charge-discharge, electrochemical impedance spectroscopy (EIS), and cycle life, respectively. The results showed that the specific capacitance can be up to 493 F g − 1 as mass ratio of γ-MnO 2 /PANI was 1:5 at current density of 0.5 A g − 1 , suggesting the γ-MnO 2 /PANI (1:5) composite as an electrode material for super capacitors has great development prospects.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 74
·46529-46535
·
IF 3.108
Hengfa Liu,Bentian Zhang,Wanping Li,Gao Cheng,Jiaxi Han,Bang Lan,Ming Sun,Lin Yu
Hierarchical pine tree-like α-MnO2 architectures are prepared by a facile one-step method without any template. The hierarchical α-MnO2 is composed of branched α-MnO2 short nanorods assembled onto the backbone of an α-MnO2 long nanowire. Time-dependent experiment shows that the growth process of the branched α-MnO2 nanostructures is the formation of β-MnOOH and then the transformation to a α-MnO2 branched structure in a step by step manner. Owing to its specific structure features, the hierarchical pine tree-like α-MnO2 exhibits superior catalytic performance in the catalytic combustion of dimethyl ether with a light-off temperature (T10) at 169 °C and a complete conversion temperature (T90) of 235 °C, which is far better than commercial MnO2.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2025
·
IF 5.5
Qiangshuai Wang,Sengui Liang,Jinshuo Liu,Yuanyuan Xie,Qi Pang,Zhao-Qing Liu,Yibo Chen
Photocatalytic conversion of carbon dioxide (CO2) to carbon-based fuels is a promising approach to alleviating environmental and energy problems. Therefore, designing photocatalysts with morphological structures that favor gas–solid reactions and exhibit exceptional catalytic efficiencies is strongly demanded. In this work, a porous-framed heterostructure, constructed by anchoring Cs4PbBr6 perovskite nanocrystals on MnO2 hollow spheres, exhibits a 1.8-fold enhancement in the total electron consumption rate (95.3 μmol g–1 h–1) for CO2 photoreduction compared to the original Cs4PbBr6 nanocrystals. Detailed optoelectronic characterizations and theoretical calculations demonstrate that the electronic interactions in the heterointerface trigger disproportionation of Mn and help to expose active Mn sites that attract electrons, thus improving the CO2 activation and the following hydrogenation step to produce COOH*. The open and through porous structure also contributes to the enhanced reaction rate by accelerating mass transfer during the photoreduction reaction. This study provides valuable insights for the development of efficient catalysts for CO2 photoreduction in gas–solid reactions.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2022
·Vol. 17
·期 2
·217-225
·
IF 4.803
Xie Jiwei,Liu Guijing,Wang Kaikai,Li Xueming,Bai Yusen,Gao Shanmin,Fan Leqing,Zheng Rundou
Aqueous zinc-ion batteries are attracting considerable attention because of their high safety compared with conventional lithium-ion batteries. Manganese-based materials have been widely developed for zinc-ion batteries cathode owning to their low cost, high security and simple preparation. However, the severe volume expansion and poor stability during charging and discharging limit the further development of manganese-based cathodes. Herein, superior α -MnO 2 @g-C 3 N 4 was successfully prepared for stable zinc-ion batteries (ZIBs) cathode by introducing g-C 3 N 4 nanosheets. Compared with pure α -MnO 2 , α -MnO 2 @g-C 3 N 4 has a specific capacity of 298 mAh·g –1 at 0.1 A·g –1 . Even at 1 A·g –1 , the α -MnO 2 @g-C 3 N 4 still retains 100 mAh·g –1 (83.4% retention after 5000 cycles), implying its excellent cycling stability. The α -MnO 2 @g-C 3 N 4 -based cathode has the highest energy density (563 Wh·kg –1 ) and power energy density (2170 W·kg –1 ). This work provides new avenues for the development of a wider range of cathode materials for ZIBs.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
·
2025
·
IF 4.7
Meng-si WANG,Yan ZHANG,Xiao-gang LUO,Lin TANG,Shan XIANG,Ru GUO,Xue-fan ZHOU,Ke-chao ZHOU,Dou ZHANG
MnO 2 -doped Ca 0.97 Bi 2.03 Nb 2 O 9 ceramics with greatly improved piezoelectric performance were prepared via conventional solid state sintering method. The effects of MnO 2 doping on the microstructure and electrical properties of Ca 0.97 Bi 2.03 Nb 2 O 9 ceramics were studied. X-ray diffraction (XRD) analysis and Rietveld refinement revealed a reduction in orthorhombicity with MnO 2 doping, which contributed to the enhancement of the piezoelectric properties. Furthermore, the introduction of MnO 2 lowered the sintering temperature, thereby reducing the formation of oxygen vacancies in the ceramic. The optimal performance was achieved in the Ca 0.97 Bi 2.03 Nb 2 O 9 −0.3wt.%MnO 2 sample, exhibiting a piezoelectric coefficient ( d 33 ) of 13.6 pC/N, a DC resistivity of 3×10 6 Ω·cm at 500 °C, and a Curie temperature of 965 °C. Additionally, all doped samples demonstrated excellent thermal stability over a wide temperature range, from room temperature to 900 °C.
研究领域:
材料科学
·
固态物理
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2022
·
IF 4.654
Zhuoxun Li,Tao Feng,Peng Zhou,Rubing Zhang,Gang Liu
Zeolitic imidazolate framework (ZIF)-supported flower-like porous MnO2 (ST@ZIF-67/MnO2) was fabricated through SiO2-guided preparation of the ZIF precursor and subsequent in situ synthesis and deposition of MnO2. The specific porous structure can effectively shorten the ion transport channels, expose more active sites, and improve the tolerance toward volume expansion during the cyclic process, thus resulting in enhanced supercapacitive properties. Typically, the ST@ZIF-67/MnO2-based electrode delivered a high specific capacitance of 278.6 F g–1 at 0.5 A g–1, which is almost 10 times that of pristine ZIF-67 and 1.5 times that of the composite without using the SiO2 template (ZIF-67/MnO2). Additionally, the electrode showed good electrochemical cycling stability with 80.3% retention after 10, 000 cycles at 10 A g–1. Our strategy of growing porous transition metal oxides on ZIFs provides a viable pathway for developing efficient electrode materials for energy storage devices.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Yao-Hui Zhang,Wen-Xiu Qiu,Mingkang Zhang,Lu Zhang,Xian-Zheng Zhang
Here, a tumor-targeted MnO2 motor nanosystem (designed as MG/HA) was constructed by the assembly of glucose oxidase (GOD), manganese dioxide (MnO2), and glycoprotein CD44-targeting polymer hyaluronic acid (HA) to elevate cancer-starving therapy efficacy in solid tumor. Upon the specific uptake of MG/HA by CD44 overexpressed cancer cells, GOD catalyzed the oxidation of glucose into gluconic acid and hydrogen peroxide (H2O2) accompanying the consumption of oxygen (O2). Meanwhile, MnO2 would react with H2O2 and acid to generate O2, which is in turn supplied to the glucose-depletion process, running like a loop. As a result, MnO2 is displayed as a motor to promote the rate of glucose depletion that contributed to the starving therapy. In contrast to G/HA, MG/HA could not only achieve effective glucose consumption to depress cancer progression, but also alleviate hypoxia and reduce the expression of Glut1 to inhibit the metabolism for further restraining the tumor aggressiveness and metastasis. The concept of MnO2 motor shows a promising prospect to overcome the restriction of the starving therapy.
研究领域:
肿瘤学
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生物医学工程
·
药剂学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yanlin Zheng,Fei Li,Xiaohui Zhu,Min Wang,Yuantao Wen,Tao Zeng,Wukun Zhong,Chao Xing,Chunhua Lu
Photodynamic therapy (PDT) holds great promise for treating various types of cancer. However, its clinical advancement is hindered by the intrinsic hypoxic tumor microenvironment, which reduces PDT efficacy, and safety concerns related to the biological specificity of photosensitizers. Here we constructed a MnO 2 nanosheet based DNA tetrahedron-photosensitizer (TMPyP4) nanoplatform (TPM), which integration with tumor targeting (aptamer), gene drugs (DNAzyme) and photosensitizer agents for enhanced PDT. Once the TPM entered cancer cells through aptamer targeting, the MnO 2 nanosheet reacts with endogenous acidic and H 2 O 2 to generate Mn 2+ and oxygen (O 2 ), thereby alleviating the tumor hypoxic. Subsequently, TMPyP4 further converts the generated O 2 into singlet oxygen ( 1 O 2 ) under near-infrared light, enhancing PDT efficacy both in vitro and in vivo. Specifically, the generated Mn 2+ activates the DNAzyme and accelerate tumor target mRNA cleavage, resulting in effective PDT-gene synergistic therapy for tumors. This work offers novel perspectives on advancing precise and highly effective gene-PDT systems.
研究领域:
生物医学工程
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肿瘤学
·
纳米医学
✓ 已验证
产品关联
DOI
高影响因子
ChemistrySelect
·
2024
·Vol. 9
·期 40
·e202403768
·
IF 1.9
Dadaso D. Mohite,Sachin S. Chavan,Vijay K. Kurkute,P. E. Lokhande,Vishal Kadam,Chaitali Jagtap,Udayabhaskar Rednam,Mushtaq Ahmad Ansari,Yedluri Anil Kumar
Graphical MnO 2 -doped PAN carbon nanofibers are created via electrospinning and subsequent carburization, with the resultant fibers serving as electrodes in supercapacitors. The individual electrode derived from these CNFs demonstrates exceptional specific capacitance and cyclic stability. Moreover, the fully solid-state asymmetric supercapacitor assembled with this electrode material exhibits remarkable electrochemical behavior. Supercapacitors (SCs) are crucial for high-performance energy storage, offering high power density, swift charge–discharge rates, and durability. The enhancement of their performance hinges on the development of advanced electrode materials. This study presents an innovative method involving polyacrylonitrile (PAN) nanofibers adorned with manganese dioxide (MnO₂) nanoparticles (NPs), created through electrospinning and subsequent thermal treatment. This synergy exploits the extensive surface area and electrical conductivity of PAN nanofibers along with the substantial capacitance of MnO₂. The MnO₂-coated PAN nanofibers reached an impressive specific capacitance of 247 F g −1 at a scan rate of 10 mVs −1 , markedly boosting the efficacy of all-solid-state asymmetric SCs. The SCs, incorporating a polyvinyl alcohol (PVA)/potassium hydroxide (KOH) gel electrolyte, exhibited an energy density of 8.2 Wh kg −1 at a power density of 700 W kg −1 , preserving 80.4% of their original capacitance after 5000 cycles. This research is pioneering in combining MnO₂ with PAN nanofibers, marking a significant leap forward in supercapacitor technology with enhanced energy storage capacity and prolonged stability. These findings underscore the promise of these composite materials in future energy storage solutions.
研究领域:
材料科学
·
能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2013
·Vol. 2
·期 7
·2374-2382
·
IF 0
Bo Zhi,Hong Ding,Dongmei Wang,Yu Cao,Ye Zhang,Xue Wang,Yunling Liu,Qisheng Huo
Ordered mesoporous MnO2 nanoarrays were successfully prepared via a vacuum-assisted nanocasting route from an SBA-15 template. To achieve better purification performance for As(III), iron oxides with varied ratios were dispersed into the 2D hexagonal channels, and a series of FeMn-x adsorbents were obtained. Consisting of both iron and manganese oxides, these adsorbents could realize powerful oxidation and effective adsorption of As(III) simultaneously, revealing a synergetic arsenic removal process. The saturation adsorption capacity was 10.55 mg g−1 and >95% adsorption stability could be reached within a relatively short time. Furthermore, owing to the optimum Fe/Mn ratio, the FeMn-2 sample could easily bring the residual concentration down to below 10 ppb, when dealing with trace As(III) concentrations as low as 300 ppb, which provides a convenient method to efficiently capture trace As(III) from water for in-depth purification.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Ling Zhang,Qi Liu,Yuxin Wang,Chunling Xu,Jiaying Bi,Daobin Mu,Borong Wu,Feng Wu
The practical application of high energy density and cost-effective lithium-sulfur batteries is still impeded by such factors as insulation nature of sulfur/lithium sulfides and poor cycling lifespan. Here, an integrated sulfur-containing cathode (S cathode) with modified γ-MnO 2 as the sulfur host is fabricated to address the capacity decline during cycling. When coupled with pre-lithiation and molybdenum doping, the electronic and ionic conductivity of the modified γ-MnO 2 host is enhanced, which reduces the cycling voltage hysteresis of the S cathode. The modified γ-MnO 2 shows strong chemisorption with the intermediate polysulfides that are generated unavoidably during lithium ions intercalation/deintercalation of a S cathode, and presents role of electrochemical catalysis for discharge/charge process to accelerate the redox kinetics of the polysulfides. Consequently, the prepared S cathode demonstrates highly enhanced performance, with an initial specific capacity of 1441 mAh g −1 at a rate of 0.1C, and a maximum areal capacity of 5.37 mAh cm −2 with sulfur loading of 5.8 mg cm −2 . The cycling stability is superior with a capacity retention of 617.2 mAh g −1 at 2C after 500 cycles, and good rate capability is also achieved. This S cathode offers a potential alternative for high-performance lithium-sulfur batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2022
·Vol. 12
·期 10
·1250
·
IF 4.501
Lei Zhao,Tingting Yu,Bing Yang,Huilin Guo,Lifen Liu,Jinlong Zhang,Changfei Gao,Tao Yang,Mingyan Wang,Yu Zhang
Unlike many studies on the preparation of Z-scheme heterojunctions by doping precious metals, in this paper we first prepared a core-shell material obtained by C doping in ZnO and then composite with MnO2to form a heterojunction; that is, a low-cost and highly catalytic ternary composite catalyst was prepared by a simple hydrothermal reaction. Meanwhile, a large amount of experimental data have enabled the heterostructure type as well as the mechanism of photocatalytic performance to be fully demonstrated. It is proven that C as an intermediate medium achieves electron transport while making up the deficiency of ZnO, and constitutes an all-solid state Z-scheme heterojunction, which enables the rapid transfer of photogenerated electron pairs and visible light irradiation to the stream to improve the photocatalytic performance of the composite photocatalyst. In terms of examination of degradation performance, this catalyst showed a high photodegradation rate of tetracycline hydrochloride (TC) of 92.6% within 60 min, and the surface ZnO-C/MnO2catalysts also showed good degradation effect on practical petrochemical wastewater in CODcr degradation experiments.Keywords:ZnO-C/MnO2;Z-scheme heterojunction;wastewater purification;mechanism exploring
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）