ACS Applied Materials & Interfaces
·
2017
·
IF 7.504
Xueyi He,Guangwei He,Anqi Zhao,Fei Wang,Xunli Mao,Yongheng Yin,Li Cao,Bei Zhang,Hong Wu,Zhongyi Jiang
Nafion, as a state-of-the-art solid electrolyte for proton exchange membrane fuel cells (PEMFCs), suffers from drastic decline in proton conductivity with decreasing humidity, which significantly restricts the efficient and stable operation of the fuel cell system. In this study, the proton conductivity of Nafion at low relative humidity (RH) was remarkably enhanced by incorporating multifunctional graphene oxide (GO) nanosheets as multifunctional fillers. Through surface-initiated atom transfer radical polymerization of sulfopropyl methacrylate (SPM) and poly(ethylene glycol) methyl ether methacrylate, the copolymer-grafted GO was synthesized and incorporated into the Nafion matrix, generating efficient paths at the Nafion–GO interface for proton conduction. The Lewis basic oxygen atoms of ethylene oxide (EO) units and sulfonated acid groups of SPM monomers served as additional proton binding and release sites to facilitate the proton hopping through the membrane. Meanwhile, the hygroscopic EO units enhanced the water retention property of the composite membrane, conferring a dramatic increase in proton conductivity under low humidity. With 1 wt % filler loading, the composite membrane displayed the highest proton conductivity of 2.98 × 10–2 S cm–1 at 80 °C and 40% RH, which was 10 times higher than that of recast Nafion. Meanwhile, the Nafion composite exhibited a 135.5% increase in peak power density at 60 °C and 50% RH, indicating its great application potential in PEMFCs.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2023
·
IF 3.3
Xinjia Zhang,Yanchao Li,Jianguo Mi,Xiuqing Kang,Junsu Jin
Atmospheric water adsorption at low humidity is considered to be a major challenge in solving global water problems. As a routine water adsorbent, the University of Oslo-66 (UiO-66) powder has been restricted by its limited low-pressure water absorption capacity, the need for powder molding, and insufficient adsorption rates. To overcome these problems, this work prepares E-UiO-66@PAA spherical composites by crystallizing UiO-66 on the surface of macroporous polyacrylate, i.e. PAA porous spheres, through in situ confined growth and ligand exchange strategies. The average size of the crystals has been reduced by 4 times vtihe nanoscale roughness of the polymer substrate surface and the interfacial enrichment of the precursor solution to lower the energy barriers of heterogeneous nucleation. In addition, the coordination of the hybrid ligand with Zr 4+ creates a unique cavity structure and gives rise to novel micropores as a result of ligand defects, which can be fitted into the lattice as binding sites for water. In the water vapor adsorption test at 298 K, E-UiO-66@PAA was able to operate at 4.9 times the capacity at low pressure (0.1 < P/P 0 < 0.2) and advanced the adsorption saturation time by 30.7% of the pristine UiO-66. Especially, the relative pressure of the sudden change in water vapor uptake was reduced from 0.3 to 0.1, which could greatly save the energy required for vapor regeneration and reduce its operating cost. This study provides an effective method to improve the adsorption capacity, mass transfer rate, and workability of composites by designing a nanoporous structure and confined growth nuclei as adsorption sites.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2021
·
IF 3.171
Jianhui Li,Yi Wang,Yang Chen,Qizhao Xiong,Jiangfeng Yang,Libo Li,Jinping Li
Harvesting water from the atmosphere is an important process to solve the extreme lack of water resources in arid regions. Adsorption-based atmospheric water harvesting (AWH) takes advantage of solar thermal energy to harvest water from air. This technique is particularly suitable for arid regions characterized by low humidity and an abundance of sunshine. Nonetheless, under low humidity conditions, AWH is highly dependent on water-adsorbing materials exhibiting excellent performance. In this work, a metal–organic framework (MOF), namely [Zn 2 (bpy)(btec)(H 2 O) 2 ]·2H 2 O, also denoted as MWH-1, was investigated for application in water harvesting under low humidity conditions (<20%). Notably, MWH-1 displayed outstanding water and thermal stability. At temperatures of 293–333 K and low pressure, activated MWH-1a exhibited competitive water uptake (relative humidity (RH) = 5%, uptake>200 cm 3 ·cm −3 ; RH = 10%, uptake>250 cm 3 ·cm −3 ). This ensured effective water harvesting at high temperatures during the day. In situ powder X-ray diffraction and Fourier-transform infrared analyses confirmed the sensitive water adsorption process of MWH-1a. The X-ray single-crystal study further demonstrated that single-crystal structures could be completely restored following water harvesting. MWH-1 showed good structural stability and enabled water harvesting under low humidity and high temperature conditions. Thus, it has the potential for application in round-the-clock water harvesting in extremely arid regions.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Jiyan Li,Guoyu Xing,Min Qiao,Silu Du,Tao Zhou,Shuo Gao,Hanxue Sun,Rui Jiao,An Li
Solar-driven atmospheric water harvesting (SAWH) has been recognized as a promising strategy to alleviate the freshwater crisis. Herein, we developed an efficient porous polymeric foam, LiCl@CCP-PPy, which has low preparation cost, strong adaptability and portability, and is very suitable for use as a wicking material in SAWH systems. LiCl@CCP-PPy contains abundant –NH 2 and –OH groups. These hydrophilic groups and excellent pore structure (porosity is 80.22 %) make it have a good moisture absorption effect even in low humidity environment. The moisture absorption capacity can reach 2.86 g/g at 35 % RH and 25 °C, and 4.48 g/g at 25 °C and 90 % RH. The saturated water absorption effect was 27.48 g/g. LiCl@CCP-PPy can be scaled up for production. In addition, LiCl@CCP-PPy has a high light absorption rate of more than 90 %, and the strong photothermal conversion ability of Polypyrene (PPy) enables the material to warm up rapidly under natural light, thereby accelerating the desorption process (96 % desorption rate at 1 kW/m 2 for 3 h). Based on the above properties, LiCl@CCP-PPy was applied to the Tengger desert in northwest China. The final water production efficiency was 0.64 L/m 2 /d, and the collected water quality met the international drinking water standard.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2023
·
IF 9.5
Lili Liu,Linxing Shi,Jianzhou Lv,Qingqiang Sun,Yuanyuan Zhang,Zengguang Huang,Zhaoxia Hu,Shouwen Chen
Two-dimensional (2D) nanosheets possessing large specific surface area and high aspect ratio can serve as proton-conduction accelerators owing to their continuous proton transport feature. Herein, phosphotungstic acid (HPW) is chemically grafted to mesoporous carbon nitride nanosheets (CN) via a hydrothermal process to produce water-insoluble HPW/CN (PCN) nanofillers, and subsequently embedded into sulfonated poly(arylene ether sulfone) (SPAES) to develop a long-range proton transport channels for high-performance composite membranes . The loading of hydrophilic HPW enhances the dispersivity and compatibility with the SPAES polymer and improves the mechanical-dimensional-chemical stability of the composite membranes. The formed hydrogen-bonding networks and acid-base interactions between fillers and polymers could endow the SPAES/PCN membranes with favorable water-absorption ability and proton-conducting performance. Besides, the excellent interfacial interactions working as a “bridge” facilitates the formation of well-defined phase-separation structure and constructs long-range ionic/water channels at the SPAES-PCN interface. Moreover, the strong acidic HPW on surface and mesoporous structure of CN enhance effectively water-retention ability of the composite membranes, which is specially contribute to rapid proton transport at low humidity. The proton conductivity of the SPAES/PCN-7.5 membrane reaches up to 250 mS cm −1 at 90 °C, hydrous condition, and 46 mS cm −1 at 80 °C, 50 % RH, which are 42 % and 84 % higher than those of the control SPAES membrane, respectively. The SPAES/PCN-7.5 membrane achieves highest maximum power density of 404–824 mW cm −2 at 80 °C and 50%–100 % RH, exceeding that of the SPAES membrane (207–546 mW cm −2 ) and Nafion® 112 (359–723 mW cm −2 ). It still remains stable cell performance, as well as undergoes lower voltages loss and hydrogen permeation after the durability test (144 h, 80 °C/60 % RH). In addition, molecular dynamics simulation analysis is performed to offer new insight into elucidating the structure-property relationships of the composite membrane. These results indicate that the SPAES/PCN composite system is an advanced membrane for the practical applications of fuel cells.
研究领域:
材料科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
Marine Drugs
·
2024
·Vol. 22
·期 10
·443
·
IF 4.9
Hengjie Su,Xiaoqi Chen,Linna Mao,Ting Li
The electrospinning of pure chitosan nanofibers is highly sensitive to environmental humidity, which limits their production consistency and applicability. This study investigates the addition of sodium chloride (NaCl) to chitosan solutions to enhance spinnability and mitigate the effigurefects of low humidity. NaCl was incorporated into the electrospun chitosan solution, leading to increased conductivity and decreased viscosity. These modifications improved the electrospinning process. Comparative analyses between chitosan membranes (CM) and sodium-chloride-added chitosan membranes (SCM) revealed no significant differences in chemical structure, mechanical strength, or in vitro cell proliferation. This indicates that the addition of 1% (w/v) NaCl does not adversely affect the fundamental properties of the chitosan membranes. The findings demonstrate that NaCl addition is a viable strategy for producing electrospun chitosan nanofibers in low-humidity environments, maintaining their physicochemical properties while enhancing spinnability.
研究领域:
材料科学
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生物医学工程
·
高分子科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2020
·
IF 7.1
Yong Zhang,Jianxu Ren,Yiwei Wu,Xiangli Zhong,Tao Luo,Juexian Cao,Mengqi Yin,Mingpeng Huang,Zhiyong Zhang
Ultra-low humidity detection is significant in some important industrial fields, such as integrated circuit manufacturing, chip packaging. However, the traditional ionic-type humidity sensor is not competent for the detection of ultra-low humidity, but can only realize the detection of medium humidity to high humidity. Here, moisture-induced discoloration material Nickel(II) iodide (NiI 2 ) is found to be highly sensitive to moisture, and both its electrical properties and color will change with environmental humidity variation. Especially, NiI 2 exhibits the largest impedance change to date in the ultra-low humidity range compared with state of the art. The impedance variation is up to 2 orders of magnitude in the range of 0.4 %–11 % RH, which means that NiI 2 can realize the detection of ultra-low humidity. The excellent performance of NiI 2 in ultra-low humidity is attributed to the material transition characteristics susceptible to humidity rather than the traditional surface mechanism of water adsorption. Moreover, combining the reversible black-to-transparency moisture-induced discoloration behavior with humidity sensing properties, a flexible wristband based on NiI 2 is developed to realize the dual-mode detection of wide range environmental humidity. These results demonstrate that NiI 2 has great application prospects in professional ultra-low humidity detection and wearable humidity detection equipment.
研究领域:
材料科学
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
TOXICOLOGICAL AND ENVIRONMENTAL CHEMISTRY
·
2018
·
IF 0.972
Zhiyong Xiong,Bing Li,Lin Li,Xiaolong Peng,Yongpo Yin,Longmei Weng
Acrylamide (AA) is a potential human carcinogen, genotoxicant, and neurotoxicant. Thus, the aim of this study was to examine the ability of mercapto flavor compounds to remove AA released from consumer packaging into food products. Four mercapto flavor compounds including 1,2-ethanedithiol, 1-butanethiol, 2-methyl-3-furanthiol, and 2-furanmethanethiol were employed to extract AA in model system using high temperature and low humidity. Our study showed that mercaptans were effective in eliminating AA in our model system. In order to remove 0.2 μmol AA, the optimal conditions in the reaction system were mercaptan flavor chemicals at 5 μmol, temperature 180 °C, and reaction time 25 min. In the presence of a higher pH, the greater was the amount of AA eliminated. Evidence indicates that employment of mercapto flavor chemicals under certain temperature and pH conditions is a reliable method to remove any unwanted AA from food products.
研究领域:
食品安全
·
食品科学
✓ 已验证
产品关联
DOI
高影响因子
HIGH PERFORMANCE POLYMERS
·
2020
·
IF 1.568
Xiang Sun,Fan Zhu,Xiaoyang Liu,Hongqian Ren,Minglong Xia,Mengjie Yang,Yi Feng,Huili Ding
The development of a proton exchange membrane (PEM) that can avoid rapid decay of proton conductivity under low humidity is of great significance for the practical application of PEMFC. In this study, acid–base core–shell microspheres (PCSMs-MA@TAC) with a carboxylic acid core and a triazine shell were synthesized by distillation-precipitation polymerization using cross-linked carboxylic acid microspheres (PMAA) as seeds. These PCSMs were then incorporated into a sulfonated poly(ether ether ketone) matrix to make hybrid membranes. Incorporation of PCSMs microspheres can not only strengthen the vehicle mechanism by increasing the water uptake of the membrane, but also the acid–base pairs formed at the SPEEK/PCSMs interface provide a new low-energy barrier pathway for proton hopping, thereby enhancing the proton conduction of the Grotthuss mechanism. The results show that when the content is 10 wt%, the proton conductivity of the SPEEK/PCSMs-MA@TAC composite membrane can reach 0.161 S cm−1 at 80°C and 100% RH, which is 19.3% higher than the SPEEK control membrane (0.135 S cm−1). In particular, even at 60% RH, the proton conductivity of the SPEEK/PCSMs-MA@TAC-10 composite membrane is still 67 mS cm−1, which is 3.16 times higher than that of the SPEEK membrane. Therefore, the SPEEK/PCSMs-MA@TAC composite membrane can maintain superior performance even under high temperature and low humidity conditions.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
FlatChem
·
2023
·
IF 6.2
Shao-Zhen Luo,Zhi-Hua Fu,Jian-Ze Xiao,Xiao-Liang Ye,Qian Liu,Guan-E Wang,Gang Xu
Acid-base pairs synergistic strategy is one of the most effective ways to improve the proton conductivity of materials at low humidity. However, the random distribution of acid or base functional groups on the surface of the materials are difficult to form long-range ordered proton transfer channels, which hinders the proton conductivity. Herein, two organic metal chalcogenides (OMCs), Ag(SPh-NH 2 ) and Ag(SPh-COOH) nanosheets were self-assembled into composite membranes by vacuum filtration. Benefiting from the long-range ordered acid-base functional groups on the surface of OMCs, the proton conductivity was significantly enhanced. As a result, the proton conductivity of the Ag(SPh-NH 2 )/Ag(SPh-COOH) composite membrane is greatly improved at a low humidity condition of 45% RH, reaching the level of the single membrane at high humidity. In addition, the proton conductivity of Ag(SPh-NH 2 )/Ag(SPh-COOH) composite membrane is 47 times higher than that of Ag(SPh-NH 2 ) membrane and 10 times higher than that of Ag(SPh-COOH) membrane under high-temperature hydration state. Collectively, this study broadens the avenue for designing proton-conducting materials that can work under low humidity conditions.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2020
·
IF 7.489
Jiarui Du,Guangli Yu,Huiming Lin,Pengfei Jie,Feng Zhang,Fengyu Qu,Chen Wen,Lei Feng,Xiaoqiang Liang
A series of composites have been fabricated by introducing ionic liquid (IL) (ship) into chromium terephthalate MIL-101 (bottle) by ship-in-bottle method (IL@MIL-101s), the resulting IL@MIL-101s are endowed to high water retention, which is essential to proton conducting on multiple energy-involved applications at the low relative humidity (RH). The humidifying IL can lower water loss and increase water uptake, and thus improves water retention properties of the composites aided by the mesoporous MIL-101 at low RH. The hydropenic proton transfer pathways are modeled inside MOF and between IL–MOF, diminishing energy barrier routes for proton hopping, and thus a promotive proton transfer is rendered via Grotthuss mechanism. Specially, the IL@MIL-101 (SIB-3) unfolds a high proton conductivity (σ = 4.4 × 10 −2 S cm −1 ) at RH as low as ~23%, five orders of magnitude increase than that of parent MIL-101 (1.1 × 10 −7 S cm −1 ) at 323 K. Besides, IL@MIL-101s as fillers are incorporated into polymer blends to form hybrid membranes, appearing the relatively high proton conductivity (4.3 × 10 −3 S cm −1 ) under ~23% RH at 323 K.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Ke Wu,Zhimin Yang,Sen Liu,Xishuang Liang,Teng Fei,Tong Zhang
Numerous applications require low humidity sensors that not only sensitive but also stable, small hysteresis, high resolution and fast response. However, most reported low humidity sensors cannot possess these properties at the same time. In this work, inspired by sea urchin , we developed an ionic liquid (IL) modified metal organic framework (UiO-66) based low humidity sensor. Owing to the synergistic effect of the hydrophilicity and ionic conductivity of IL and the steric hindrance effects of UiO-66, the optimized low humidity sensor simultaneously exhibits high response (47.5), small hysteresis (0.3 % RH), ultrafast response speed (0.2 s), high resolution (1 % RH), and excellent long-term stability (>120 days). In particular, the sensor has been proved to have potential applications in visual humidity detection and water source location. This work provides a preliminary design principle that will contribute to the preparation of high-performance low humidity sensing materials.
研究领域:
材料科学
·
传感器技术
·
仿生学
✓ 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）