Small Methods
·
2024
·Vol. 8
·期 7
·2301233
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IF 10.7
Xiaolin Ye,Ningxin Xiong,Shaopei Huang,Qixing Wu,Hongning Chen,Xuelong Zhou
Tin-based hybrid flow batteries have demonstrated dendrite-free morphology and superior performance in terms of cycle life and energy density. However, the quick accumulation of electrodeposits near the electrode/membrane interface blocks the ion transport pathway during the charging of the battery, resulting to a very limited areal capacity (especially at high current density) that significantly hinders its deployment in long-duration storage applications. Herein, a conductivity-activity dual-gradient design is disclosed by electrically passivating the carbon felt near the membrane/electrode interface and chemically activating the carbon felt near the electrode/current collector interface. In consequence, the tin metals are preferentially plated at the region near electrode/current collector, preventing the ion transport pathway from being easily blocked. The resultant gradient electrode demonstrated an unprecedentedly high areal capacity of 268 mAh cm −2 at a current density of as high as 80 mA cm −2 . Numerical modeling and experimental characterizations show that the dual-gradient electrode differs from conventional electrodes with regard to their reaction current density distribution and electrodeposit distribution during charging. This work demonstrates a new design strategy of 3D electrodes for hybrid flow batteries to induce a desirable distribution of electrodeposits and achieve a high areal capacity at commercially relevant current densities.
研究领域:
电化学储能
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材料科学
·
能源化学
·
电池技术
·
功能材料
·
电化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2016
·
IF 2.196
Peizhu Zheng,Dongxing Cai,Jihua Zhao,Weiguo Shen
The mixed surfactants of dodecyltrimethylammonium bromide (DTAB) and 1-dodecyl-3-methylimidazolium bromide (C 12 mimBr) in aqueous solutions were studied by measurement of electrical conductivity and isothermal titration microcalorimetry (ITC). The critical micelle concentrations (cmc) and the degree of dissociations of counter ions were determined for this system at various surfactant compositions, and the thermodynamic properties of micellization were evaluated. A one-parameter Margules equation was used to fit the cmc values to calculate the mole fraction, the activity coefficients of two surfactant components and the excess properties in mixed micelles.
研究领域:
胶体化学
·
物理化学
·
表面化学
·
热力学
·
溶液化学
✓ 已验证
DOI
高影响因子
COMBUSTION AND FLAME
·
2021
·
IF 4.185
Jizhen Zhu,Sixu Wang,Mohsin Raza,Yuan Feng,Jing Li,Yebing Mao,Liang Yu,Yong Qian,Xingcai Lu
Methanol is an attractive oxygenate increasingly used as primary fuel for dual-fuel combustion technology yielding beneficial thermal-efficiency and emissions in modern engines. As such, it is significant to fundamentally understand the autoignition behavior of methanol/diesel mixtures. This study measured the ignition delay times (IDTs) of methanol/diesel blends with different mixing ratios (30%, 50%, 70% methanol by mol.) on a heated shock tube and a heated rapid compression machine at temperatures of 650−1450 K, pressures of 6−20 bar, and equivalence ratios of 0.5, 1.0 and 2.0. The typical two-stage ignition characteristics with the negative temperature coefficient response were observed for dual-fuel mixtures. In general, both the total and first-stage IDTs decrease with the increment of pressure and equivalence ratio as well as diesel proportion in mixtures. The simulation results performed with a published detailed mechanism in conjunction with a tri-component diesel surrogate demonstrate generally good agreement with the experimental data at all test conditions. Moreover, a crossover of IDTs occurs at a higher temperature (~1500 K) for varying equivalence ratios, and experiment and simulation both exhibit a non-linear mixing effect of methanol addition on diesel ignition. Interestingly, simulation results clearly suggest a crossover (~940 K) for mixtures with varying methanol content at an intermediate-temperature, where the IDT of the mixture with a lower methanol ratio becomes longer as the temperature is higher than that of the crossover. Furthermore, brute-force sensitivity analyses assisted with reaction path analysis were conducted to gain deeper insights into the autoignition chemistry of dual-fuel mixtures, especially for the chemical interaction between both fuels during the low-temperature oxidation process . It is found that methanol hardly generates •OH, whereas •OH is mainly produced by the low-temperature reaction pathways of diesel. Thus, •OH is the bridge for both fuels during the ignition process. At the high methanol ratio, the H-abstraction of diesel is mainly via •HO 2 while CH 3 OH consumes a large percentage of •OH. Consequently, the competition between methanol and diesel for •OH radicals inhibits the overall reactivity of reaction network. In addition, the original data reported here lay a foundation for the development and validation of more accurate and robust dual-fuel kinetic schemes.
研究领域:
燃烧化学
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燃料科学
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化学动力学
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内燃机工程
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替代燃料技术
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2016
·
IF 2.196
Rongrong Li,Jiaqi Weng,Cuihong Ye,Anguo Ying,Qizhong Zhou,Aiguo Zhong,Hao Chen,Jianguo Yang
The equilibrium solubility of sodium 2,4-diaminobenzene sulfonate in liquid mixtures (methanol + water, isopropanol + water, and 1,2-propanediol + water) were determined at temperatures ranging from (273.15 to 323.15) K. The solubility of sodium 2,4-diaminobenzene sulfonate increased with temperature increment but decreased with the concentrations of methanol, isopropanol or 1,2-propanediol in liquid mixtures. The obtained solubility data were correlated by Apelblat equation and Sun model. On the base of the measured solubility, the dissolution enthalpy ( Δ H sol o ) of the dissolution process were calculated.
研究领域:
药物化学
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物理化学
·
药剂学
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溶解行为研究
·
热力学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2022
·
IF 9.794
Xiao Yang,Minjian Ma,Chunming Xu,Rongzheng Ren,Jinshuo Qiao,Wang Sun,Kening Sun,Zhenhua Wang
Hybrid direct carbon fuel cells (HDCFCs) present its inherent and unparalleled advantages in converting chemical energy from organic waste, biomass, and coal directly into clean energy with high efficiency. However, the progress of HDCFC technology continues to be hampered by the sluggish anode reaction kinetics. Herein, an effective design strategy for HDCFC anode is proposed, a Cu-modified Sr 2 Fe 1.3 Cu 0.2 Mo 0.5 O 6-δ (SFCM) perovskite oxide is developed to meet the requirements of intermediate-temperature HDCFC anode. The Cu-doping SFCM anode demonstrates excellent redox structural stability and catalytic activity. In addition, the electrolyte-supported single cell with Cu-doping SFCM anode has improved the peak power density from 285.5 mW cm −2 to 489.3 mW cm −2 at 800 °C with activated carbon as the fuel. The significantly enhanced anode catalytic activity is primarily due to the improved interfacial activity and chemical adsorption of CO. Therefore, the present work shows an effective strategy for designing and developing novel high-performance HDCFCs anode materials .
研究领域:
能源材料
·
电化学
·
燃料电池
·
功能材料
·
催化化学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2021
·
IF 6.901
Hua Tian,Kaixin Zhu,Wang Li,Lin Wang,Zhifeng Yu,Yuannan Lai,Yunyi He
Ni-Co layered double hydroxide (NCLDH) with nitrate anions as interlayer counter ions was obtained via an oxidation-induced anion intercalation process. The optimization on the tunable proportion between divalent and trivalent metal cations in NCLDH host layers is realized in the dependence on the regulation of the additive amount of hydrogen peroxide as an oxidizing agent. The increase of trivalent metal cations facilitates the intercalation of nitrate anions into the interlamellar region between NCLDH host layers. Importantly, the electrostatic interaction between NCLDH host layers and interlayer anions results in the formation of hierarchical flower-like morphologies towards the enhancement of specific surface areas. Moreover, the increase in number of interlayer nitrate anions expands effectively interplanar spacing between NCLDH host layers. Remarkably, this unique structure not only accelerates the diffusion process of active hydroxide anions in the bulk phase of LDH, but also strengthens the stability of the hierarchical structure during electrochemical reactions. The electrochemical evaluation shows that NCLDH-16 achieves a superior specific capacity of 802 C g −1 at a current density of 1 A g −1 with a capacity retention of 86.7% as the increase of current densities to 10 A g −1 . The NCLDH-16//AC hybrid supercapacitor delivers a maximum energy density of 37.6 Wh kg −1 at a power density of 800 W kg −1 as well as still retains 87.4% of the initial capacitance after 10 000 cycles, suggesting great potential in practical energy storage devices.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米材料
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功能材料
·
电化学能量存储
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2016
·
IF 5.557
Jiayou Liao,Zhi Wang,Ming Wang,Chengyun Gao,Song Zhao,Jixiao Wang,Shichang Wang
An ion-exchange material – Poly(diallyldimethylammonium carbonate) (PDDACA) containing mobile carbonate has been prepared and it has been blended in a fixed carrier membrane material – polyvinylamine (PVAm) containing abundant amine-group to adjust the carrier microenvironment of the fixed carrier membrane. It makes the mobile carrier cruise around the fixed carrier. On one hand, the CO 2 can be transported continuously in the swing area of fixed carrier through the mobile carriers, the passivity of fixed carrier can be overcome and the utilization efficiency of fixed carrier can be enhanced. On the other hand, a loose and low crystalline system will be obtained by blending two polymers, the number of effective mobile carrier will be increased with mobile carriers unlocking from the crystalline area, and the loose and low crystalline system will provide a good environment for the movement of mobile carriers. These are conducive to enhance the performance of blend membrane in comparision with single polymer membrane. The CO 2 permeance and CO 2 /N 2 selectivity of PVAm-PDDACA membrane, which concurrently contains fixed amine carriers and movable carbonate carriers, can reach 909 GPU and 102 at 0.11 MPa, respectively. The performance of PVAm-PDDACA membrane is enhanced obviously in comparision with PVAm membrane and PDDACA membrane.
研究领域:
膜科学与技术
·
气体分离
·
高分子材料
·
化学工程
·
环境化工
·
能源材料
·
功能材料
✓ 已验证
DOI
高影响因子