ACS Applied Materials & Interfaces
·
2016
·
IF 7.145
Hongjiao Nie,Chi Xu,Wei Zhou,Baoshan Wu,Xianfeng Li,Tao Liu,Huamin Zhang
Free-standing activated carbon nanofibers (ACNF) were prepared through electrospinning combining with CO2 activation and then used for nonaqueous Li–O2 battery cathodes. As-prepared ACNF based cathode was loosely packed with carbon nanofibers complicatedly overlapped. Owing to some micrometer-sized pores between individual nanofibers, relatively high permeability of O2 across the cathode becomes feasible. Meanwhile, the mesopores introduced by CO2 activation act as additional nucleation sites for Li2O2 formation, leading to an increase in the density of Li2O2 particles along with a size decrease of the individual particles, and therefore, flake-like Li2O2 are preferentially formed. In addition, the free-standing structure of ACNF cathode eliminates the side reactions about PVDF. As a result, the Li–O2 batteries with ACNF cathodes showed increased discharge capacities, reduced overpotentials, and longer cycle life in the case of full discharge and charge operation. This provides a novel pathway for the design of cathodes for Li–O2 battery.
研究领域:
材料科学
·
储能技术
·
纳米技术
·
电化学
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2020
·
IF 3.421
Qiongqiong Jiang,Yali Cao,Xiangyu Liu,Hao Zhang,Hui Hong,Hongguang Jin
Chemical looping combustion (CLC) can achieve the benefits of efficient conversion of hydrocarbon fuels and zero-energy CO2 capture using oxygen carriers (OCs) with facilitated oxygen transport properties. The current study details the use of Cu- and Ca-doped lanthanum nickel perovskite-type materials as the OC in CLC processes. By incorporation of lanthanum nickel oxide with copper and calcium, the oxygen storage capacity and average transport rate of La1–yCayCuxNi1–xO3 are up to 7.8 wt % and 0.82 wt % min–1, respectively, during the methane CLC process at 400 °C, whereas undoped LaNiO3 cannot react with methane at a low temperature. Simultaneously, substituted lanthanum nickel oxides can decrease the oxygen transport temperature by about 70 °C compared to undoped lanthanum nickel oxide. X-ray diffraction, Brunauer–Emmett–Teller, and scanning electron microscopy of the samples were characterized in terms of particle properties and morphology to unveil the rational reasons of the high oxygen transport at lower temperatures. The enhancement of the specific surface area and stable porous morphology in La1–yCayCuxNi1–xO3 can both facilitate the oxygen transport in CLC processes. Experiments were executed to investigate the reactivity of the redox materials on the standpoints of oxygen capacity, stability, and regenerability. Hydrogen and methane as the fuels are both considered in this study. La1–yCayCuxNi1–xO3 showed favorable reactivity and stability in the successive redox cycles at low temperatures. These experimental results indicate that La1–yCayCuxNi1–xO3 can facilitate O2– transport and have the potential to be used as the promising OC for low-temperature CLC processes.
研究领域:
能源化学
·
材料科学
·
化学工程
·
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
ACS Applied Energy Materials
·
2025
·
IF 5.5
Qiang Li,Chuang Shi,Zhiguang Zhang,Hong Sun,Tian Zhang,Jie Li,Zhichao Xue,Tianyu Zhang,Mingfu Yu,Haotian Chen,Peng Zhou
Li–O2 batteries have attracted great attention due to their extremely high theoretical energy density. However, they suffer from a short cycle life and low capacity in practical applications. These problems stem from the inability to fully decompose the Li2O2 generated during the discharge process. In this study, NiFe2O4 catalysts with two different morphologies, octahedral and microflowers, were prepared by a simple hydrothermal method. The effects of NiFe2O4 cathodes with different morphologies on the performance of Li–O2 batteries were investigated. Theoretical calculations reveal that the overpotentials of the oxygen reduction reaction and oxygen evolution reaction of the battery with NiFe2O4 are 0.52 and 0.65 V, respectively. The results show that the octahedral Super-P/NiFe2O4 cathode exhibits high catalytic activity and shows a large specific surface area and a reasonable pore structure, resulting in the reduction in charge/discharge potential difference. The battery equipped with an octahedral Super-P/NiFe2O4 cathode exhibits the best cycle life of 125 cycles at a current density of 500 mA·g–1 and presents the highest discharge capacity of 9427 mAh·g–1 at a current density of 100 mA·g–1.
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Nan Meng,Fang Lian,Yadi Li,Xiaofeng Zhao,Li Zhang,Shigang Lu,Hong Li
Electrolyte is the key to constructing the ionic transport paths and O2 gas diffusion routes in the cathode as well as maintaining the electrode interfacial stability in view of the complex chemistry of Li–O2 batteries. A novel poly(vinyl formal) (PVFM)-based Janus membrane, which is prepared via coating multiwalled carbon nanotubes (MWCNTs) on the porous side of the cross-linked PVFM membrane, has been proposed herein to achieve membrane-supporting gel polymer electrolyte (GPE) for Li–O2 batteries. Within Li–O2 batteries, the dense side of PVFM-based Janus membrane demonstrates a good compatibility with lithium metal anode, while the other side with MWCNTs coating reserves much more solvent on the surface, assisting the cathode to form enlarged electrolyte-wetted interface. Moreover, the comparative studies indicate that PVFM-based Janus membrane also can provide a conductive pathway, modulate the morphology of the discharge products, and produce accommodation space for the products. So, the Li–O2 batteries containing PVFM-based Janus membrane-supporting GPE not only demonstrate significantly improved discharge capacity and cycling stability, i.e., 150 times at 1000 mAh g–1 capacity limitation, but also a narrow voltage gap of 0.90 V and an excellent rate performance up to 1000 mA g–1.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2017
·
IF 6.844
Kun Zhao,Yan Su,Xie Quan,Yanming Liu,Shuo Chen,Hongtao Yu
Electrochemical synthesis of hydrogen peroxide (H 2 O 2 ) via two-electron pathway of oxygen reduction reaction is a promising alternative to the current anthraquinone process. The H 2 O 2 production from O 2 is a competing reaction with four-electron O 2 reduction to H 2 O, and the selectivity is related to the adsorption energy of the OOH intermediate on electrocatalysts surface. Generally, the properties for binding of OOH intermediate on catalysts can be controlled by changing its electronic structure. Herein, the electronic structure of porous carbon materials was tuned by doping different types and contents of fluorine species. The yield of H 2 O 2 generation depended on the F content and the best catalytic activity toward H 2 O 2 electrosynthesis was obtained with F content of 3.41 at.%. The resultant F-doped porous carbon (FPC) catalysts exhibited good H 2 O 2 selectivity of 97.5–83.0% and the H 2 O 2 production rate could reach 112.6–792.6 mmol h −1 g −1 over the potential range of 0.2 V to −0.3 vs. RHE (pH 1). The density functional theory (DFT) calculations and experiments revealed that the incorporation of CF 2, 3 into carbon plane promotes the activation of O 2 molecule and facilitates desorption of OOH intermediate, which was crucial to H 2 O 2 synthesis.
研究领域:
材料科学
·
电化学
·
环境科学
✓ 已验证
DOI
高影响因子
Biomaterials Science
·
2020
·Vol. 8
·期 14
·3844-3855
·
IF 6.183
Huimin Zhu,Guodong Cao,Chu Qiang,YiKe Fu,Yulian Wu,Xiang Li,Gaorong Han
Nanoparticles presenting promoted catalytic activity, oxygen induction and loading capability are in high demand for effective synergistic tumor therapy. Herein, ferric-tannic acid complex nanocapsules with fine hollow microstructure (HFe-TA) are synthesized and loaded with a photosensitizer (indocyanine green, ICG) for synergistic tumor therapy. In acidic environment, ICG@HFe-TA decomposes and releases Fe3+ ions, TA and ICG molecules. Fe3+, with low catalytic activity, is effectively converted into highly catalytic Fe2+ by the reductant TA, enabling promoted efficacy of ˙OH induction. More importantly, the ROS (1O2) induction by ICG is significantly enhanced under 808 nm laser irradiation due to the O2 byproduct of Fe3+/Fe2+ conversion. In consequence, the ICG@HFe-TA nanoparticles exhibit considerable in vitro and in vivo tumor inhibition owing to the combined effect of ˙OH and 1O2 induced intracellularly. This study has therefore demonstrated a potential platform enabling combined photodynamic and chemodynamic therapy with high efficacy.
研究领域:
纳米技术
·
癌症治疗
·
材料科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Functional Materials Letters
·
2020
·
IF 2
Kaicheng Yue,Zhaoqian Yan,Zhihao Sun,Anran Li,Lei Qian
In this work, graphitic carbon nitride (g-C 3 N 4 ) was modified by Pd nanoparticles (Pd-CN) to prepare an efficient cathode catalyst for Li-O 2 batteries. The specific surface area of g-C 3 N 4 was improved to 239.56 m 2 /g by two-steps thermal polymerization. Pd nanoparticles were loaded onto the g-C 3 N 4 by K 2 PdCl 4 reduction with NaBH 4 . The resulted Pd-CN composites were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscope, and transmission electron microscope. The results proved that g-C 3 N 4 showed three-dimensional layered and porous structure, and Pd nanoparticles were successfully supported on it. The Li-O 2 batteries using Pd-CN composites as cathode catalysts were assembled and tested. The maximum initial discharge specific capacity reached 26,614 mAh g − 1 at current density of 100 mA g − 1 . The electrodes remained large capacity under high current density, meaning excellent rate capability. Li-O 2 batteries containing Pd-CN cathode were continuously cycled for 70 cycles with no loss of capacity and obvious change in the terminal voltage. These electrochemical results indicated that the loading Pd nanoparticles effectively increased specific capacity, reduced overpotential and improved the cyclic stability. The Pd-CN composites are proved to be the promising cathode catalysts for Li-O 2 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
TALANTA
·
2019
·
IF 4.916
Yue Du,Yonghai Song,Juan Hao,Keying Cai,Nan Liu,Li Yang,Li Wang
A novel ratiometric fluorescent sensor for superoxide radical (O 2 •− ) detection was developed based on Schiff base polymer (SBP)/rhodamine-B (SBP/RDB) nanocomposites. The SBP/RDB was investigated by atomic force microscopy , scanning electron microscopy, transmission electron microscopy , X-ray powder diffraction, Fourier transform infrared spectroscopy, N 2 adsorption/desorption isotherms and fluorescence spectroscopy, etc. The results showed the SBP was two-dimensional (2D) crystalline nanosheet with the thickness of 0.5 nm. RDB could be self-assembled on each of 2D SBP surface to form SBP/RDB due to the hydrogen bond between N atoms of SBP and –COOH of RDB as well as π-π interaction. The SBP/RDB exhibited the characteristic fluorescence emission of both SBP at 485 nm and RDB at 585 nm under an excitation of 270 nm. The 2D SBP was not only acted as template to assemble RDB, but also used as reference fluorescence for O 2 •− detection. The SBP/RDB fluorescence probe for O 2 •− detection demonstrated high sensitivity and selectivity with good linear range (11.1 ± 0.76 nM–8.0 ± 0.36 μM) and low detection limit (3.7 ± 0.42 nM). Because of the low cost and simple operation, the work sheds some new light to construct ratiometric fluorescent sensors based on SBP to detect O 2 •− in drinking water and human blood serum for commercial applications.
研究领域:
生物化学
·
材料科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS A-PHYSICAL
·
2019
·
IF 2.739
Md Mehedi Hasan,Feichao Zhu,Arsalan Ahmed,Nazakat Ali Khoso,Hridam Deb,Lai Yuchao,Md Zahidul Islam,Hui Sun,Bin Yu
Melt blown-Nonwoven Polypropylene based materials have numerous applications, such as nonwoven fabrics, filtration membranes used in clothing and potential industrial use due to its higher breathability, durability, absorbency, and filtration properties. Nonwoven PP-fabrics are very often used to develop wearable articles such as garments. In this research melt blown-nonwoven polypropylene (NW-PP) membranes were functionalized using (O 2 ) cold plasma for the conversion of highly hydrophobic into hydrophilic nature to enhance the absorption and adhesion of graphene films on the fiber surface. The graphene oxide (GO) and NW membrane was successfully introduced on the fibrous mat and reduced into reduced Graphene oxide (rGO) with green chemical and thermal reduction. L-Ascorbic Acid was used as a reducing agent at a low-temperature microwave-assisted reduction at 90 °C. The as developed NW membrane was connected two copper electrodes and used as wearable pressure (WP) sensors. The physical sensor responds with different stretching and bending cycles under dynamic pressure of loading and unloading. The sensitivity of the developed pressure sensor was 0.050 kPa −1 in a wide pressure range (0–60 kPa). The resultant rGO coated NW-PP wearable pressure sensor (RNPWP) is capable of responding to human body movement and motion. The study demonstrates that mass production on an industrial scale graphene-based conductive nonwoven PP fabric potentially replaces the metal-based conductive wearable textiles for physical sensors.
研究领域:
材料科学
·
纺织工程
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2013
·
IF 5.695
Lu-Lu Qu,Da-Wei Li,Li-Xia Qin,Jin Mu,John S. Fossey,Yi-Tao Long
A novel surface-enhanced Raman scattering (SERS) nanosensor was developed by modifying oxidized cytochrome c (Cyt c) on gold nanoparticles (Au NPs) for the sensitive and selective determination of intracellular superoxide anion radical (O2•–). On the basis of the differences in the SERS spectra between the oxidized and reduced form of Cyt c, this nanosensor could be employed to investigate O2•– concentration by measuring the SERS spectra of the reduced Cyt c. Using this SERS nanosensor, a detection limit of 1.0 × 10–8 M for O2•– could be attained. Additionally, the selectivity of the SERS nanosensor for O2•– was examined, showing that other reactive oxygen species (ROS) and biologically relevant species did not influence the detection of O2•–. More importantly, the nanosensor could be delivered to the living HeLa and normal human liver cells and permitted the concentration of O2•– to be monitored in real time and in a noninvasive manner, which indicates that this nanosensor will be suitable for the qualitative and quantitative analysis of O2•– in biosystems, thus leading to a greater understanding of oxidative-stress-related diseases at a cellular level.
研究领域:
生物化学
·
分析化学
·
医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials
·
2019
·Vol. 12
·期 21
·3515
·
IF 2.972
Binqing Sun,Lixin Lu,Yong Zhu
The diffusion of five flavor organic molecules, including D-limonene, myrcene, ethyl hexanoate, 2-nonanone, and linalool in low density polyethylene (LDPE) film were investigated by combined experimental and molecular dynamics (MD) simulation studies. The diffusion coefficients derived from the prediction model, experimental determination, and MD simulation were compared, and the related microscopic diffusion mechanism was investigated. The effects of the presence of the flavor organic molecules on the diffusion of O2and H2O in polyethylene (PE) were also studied by MD simulation. Results show that: The diffusion of five flavor molecules in LDPE is well followed to Fick’s second law by the immersion experiment; MD simulation indicates the dual mode diffusion mechanism of the flavor molecules is in LDPE; the diffusion coefficients from MD simulation are close to those from the experimental determination, but are slightly larger than those values; the presence of the flavor organic molecules hinders the diffusion of O2and H2O, which can be well explained from the fraction of free volume (FFV) and interaction energy calculation results derived from MD simulation.Keywords:flavor organic molecules;LDPE film;molecular dynamics simulation;diffusion
研究领域:
材料科学
·
化学工程
·
高分子科学
·
食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Chun-xian Zhou,Peng-bo Wang,Bao Zhang,Lin-bo Tang,Hui Tong,Zhen-jiang He,Jun-chao Zheng
Li-rich cathode materials are regarded as ideal cathode materials, owing to their excellent electrochemical capacity. However, residual lithium compounds, which are formed on the surface of the materials by reacting with moisture and carbon dioxide in ambient atmosphere, can impair the surface structure, injure the capacity, and impede the electrode fabrication using Li-rich materials. Exposure to air atmosphere causes the formation of residual lithium compounds; the formation of such compounds is believed to be related to humidity, temperature, and time during handling and storage. In this study, we demonstrated for the first time an artificial strategy for controlling time, temperature, and humidity to accelerate exposure. The formation and effect of residual lithium compounds on Li-rich cathode material Li1.35[Ni0.35Mn0.65]O2 were systematically investigated. The residual lithium compounds formed possessed primarily an amorphous structure and were partially coated on the surface. These compounds include LiOH, Li2O, and Li2CO3. Li2CO3 is the major component in residual lithium compounds. The presence of residual lithium compounds on the material surface led to a high discharge capacity loss and large discharge voltage fading. Understanding the formation and suppressing the effect of residual lithium compounds will help prevent their unfavorable effects and improve the electrochemical performance.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）