COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2013
·
IF 2.108
Pei Zhang,Hui Wang,Xia Liu,Xuefeng Shi,Jian Zhang,Guang Yang,Keji Sun,Jinben Wang
The dynamic surface tension and dilational viscoelasticity properties of amphiphilic polyamidoamine (PAMAM) dendrimers were investigated to probe the hydrophobic chain effect on the interfacial properties and the demulsification behaviors. The values of dynamic parameters n and t * representing diffusion speed of the molecules obtained according to the Rosen equation decreased with the increasing of bulk concentration. Taking the hydrophobic effect into consideration, the t * values decreased and n values increased with the increase of alkyl chain length, suggesting easier adsorption and faster diffusion for longer hydrophobic chain which was opposite to the tendency of traditional surfactants. Further dilational viscoelasticity studies demonstrated that the properties referring to adsorption and exchange-diffusion were probably affected by the aggregates conformation at the interface. Subsequently, from the demulsification experiments a conclusion can be drawn that the amphiphilic dendrimers with branched dendritic structure possesses superior properties of breaking W/O crude oil emulsions, showing a certain correlation to the dilational viscoelasticity properties.
研究领域:
胶体与界面化学
·
石油化学
·
高分子科学
·
流变学
·
表面活性剂化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Ruihan Wang,Nanxi Dong,Guofeng Tian,Gang Liu,Bo Zhou,Shengli Qi,Dezhen Wu
In order to allow polyimide (PI) to resist the erosion of atomic oxygen (AO) in Low Earth Orbit to extend the life of the aircraft, an in-situ precursor network approach was proposed to manufacture the inorganic gradient microstructure across the organic/inorganic transition interface and simplify the process, which create a three-tier microstructure film and lead the dense SiO 2 protective layer firmly grasps the PI film. Benefiting from the integrated structure, SiO 2 -coated PI film shows remarkable surface and interface state after 3000 times mechanical bending, which able to delay the initial AO corrosion caused by the defect of the protective layer, resistance to AO reported as AO erosion yield of 2.39 × 10 −26 cm 3 O atom −1 under 7 × 10 21 O atoms cm −2 AO fluence. This work proposes a novel approach for the fabrication of high-performance and AO resistant PI to enable the aircraft to complete more efficient and highly integrated flight missions and shows great potential in the general preparation of organic-inorganic interface.
研究领域:
高分子材料科学
·
航天材料工程
·
表面与界面化学
·
空间环境效应
·
功能涂层技术
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 1
·51418
·
IF 3.125
Lan Hao,Xulin Cui,Xiaoli Wu,Jingtao Wang,Yifan Li,Wenpeng Li,Xingzhong Cao,Haoqin Zhang
Efficient separation of aromatic-aliphatic hydrocarbon mixtures has long been an important topic in chemical industries. Organic nanofiltration (OSN) has been revealing great promise in separating solvent mixtures that has not been effectively resolved by the state-of-the-art technologies. Herein, novel OSN membranes are designed for the separation of toluene and n -heptane. Polyamide active layer with diaminonaphthalene as the aqueous phase monomer is prepared by interfacial polymerization for the first time. The addition of polydimethylsiloxane gutter layer, as well as the combination of spin coating technique and macroporous substrate, renders the membranes with loose and defect-free architectures. The as-designed membranes achieve a rather high selectivity of toluene over n -heptane (>4) together with ultra-high toluene permeance (>180 L m −2 h −1 bar −1 ). These membranes also present excellent stability in the long-term operation.
研究领域:
材料科学
·
膜分离技术
·
化学工程
·
纳米技术
·
高分子化学
·
工业催化
·
绿色化学
✓ 已验证
DOI
高影响因子
Small
·
2023
·Vol. 19
·期 39
·2302691
·
IF 13.3
Jing Yu,Guodong Zhou,Yueqing Li,Yuhao Wang,Dengjie Chen,Francesco Ciucci
Composite polymer-ceramic electrolytes have shown considerable potential for high-energy-density Li-metal batteries as they combine the benefits of both polymers and ceramics. However, low ionic conductivity and poor contact with electrodes limit their practical usage. In this study, a highly conductive and stable composite electrolyte with a high ceramic loading is developed for high-energy-density Li-metal batteries. The electrolyte, produced through in situ polymerization and composed of a polymer called poly-1,3-dioxolane in a poly(vinylidene fluoride)/ceramic matrix, exhibits excellent room-temperature ionic conductivity of 1.2 mS cm −1 and high stability with Li metal over 1500 h. When tested in a Li|electrolyte|LiFePO 4 battery, the electrolyte delivers excellent cycling performance and rate capability at room temperature, with a discharge capacity of 137 mAh g −1 over 500 cycles at 1 C. Furthermore, the electrolyte not only exhibits a high Li + transference number of 0.76 but also significantly lowers contact resistance (from 157.8 to 2.1 Ω) relative to electrodes. When used in a battery with a high-voltage LiNi 0.8 Mn 0.1 Co 0.1 O 2 cathode, a discharge capacity of 140 mAh g −1 is achieved. These results show the potential of composite polymer-ceramic electrolytes in room-temperature solid-state Li-metal batteries and provide a strategy for designing highly conductive polymer-in-ceramic electrolytes with electrode-compatible interfaces.
研究领域:
材料科学
·
电化学
·
能源存储
·
固态电池
·
高分子化学
·
无机非金属材料
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2024
·
IF 8.1
Zhengwu Wang,Yannan Zhang,Bao Zhang,Dong Yang,Kai Zhou,Yixue Huang,Fei Wang,Jianguo Duan,Xianshu Wang,Peng Dong,Yingjie Zhang
Spinel LiNi 0.5 Mn 1.5 O 4 (LNMO) has gained significant attention as a promising cathode material for lithium-ion batteries due to its high working voltage (>4.7 V) and energy density . However, challenges such as electrolyte decomposition-induced material interface erosion and transition metal dissolution under high operating voltage hinder its commercial use. In this study, a thin and uniform Sm 2 O 3 layer has been successfully deposited on the surface of LNMO using a wet chemical method . A comprehensive investigation of surface morphology , crystal structure, and electrochemical performance of the modified LNMO is conducted. The results demonstrate that the Sm 2 O 3 surface modification acts as a robust multifunctional protective layer, effectively shielding against hydrofluoric acid-induced chemical attack and enhancing the migration efficiency of lithium ions . Notably, the capacity retention rate of LNMO@Sm 2 O 3 (3 wt%) remains up to 88 % after 280 cycles, significantly surpassing the uncoated counterpart. The coated material exhibits a capacity of 114 mAh g −1 even under 10 C rate conditions. Moreover, the AC impedance values and manganese dissolution of the modified material in the organic electrolyte are considerably lower than those of the uncoated counterpart. Theoretical calculations strongly support the experimental findings, revealing higher Mn vacancy formation energy and density of states at the Fermi energy level for the Sm 2 O 3 -modified electrodes. This research contributes to the field of surface modification and paves the way for further enhancements in the electrochemical performance of other high-voltage manganese-based lithium-ion batteries (LIBs).
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
纳米技术
·
表面工程
·
锂电池
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）