Environmental Science-Nano
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2018
·Vol. 5
·期 12
·3004-3010
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IF 6.087
Gaoliang Wei,Xie Quan,Chao Li,Shuo Chen,Hongtao Yu
Membranes have shown excellent performance in water treatment but still suffer from two important technical limitations—the compromise between permeability and selectivity, and membrane fouling. Empirical evidence suggests that ultrathin membranes may achieve the ultimate permeation and the preclusion of irreversible fouling. Considering the atomic thickness of graphene, we present for the first time a direct growth method of molecularly thin porous graphene membranes, through a synchronous thermal conversion and chemical etching process. Such graphene membranes allow for ultrafast water permeation, affording a permeance of up to 182 000 L m−2 h−1 bar−1, which is 2 orders of magnitude higher than that of conventional membranes, with a similar pore size of approximately 50 nm, and comparable to that of the reported state-of-the-art membranes. Additionally, much higher recalcitrance to irreversible fouling (in terms of higher flux recovery after a simple hydrodynamic flush) is observed, compared with polyvinylidene fluoride ultrafiltration membranes, during the filtration of engineered polystyrene nanoparticles and humic acid molecules. Both the high permeability and resistance to irreversible fouling of the graphene membranes can be attributed to their molecularly thin structure, perpendicular pore channels and appropriate surface chemistry.
研究领域:
材料科学
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环境工程
·
纳米技术
✓ 已验证
DOI
高影响因子
DESALINATION
·
2024
·
IF 8.3
Leyao Liu,Yunchen Wu,Luzheng Peng,Yan Lv,Qianqian Lan,Tianxi Liu
Laminar separation membranes stacked by graphene and its derivatives hold the merit of controlled mass transfer behaviors. However, precise ion separation is challenged by the disordered assembly of nanosheets on macroporous substrates with complicated surface properties. Herein, we prepare ultrathin ordered graphene membranes by an intermediate layer assisted stacking method. Nanoporous covalent organic framework (COF) nanosheets are first vacuum-filtered on macroporous substrates, followed by deposition and thermal reduction of graphene oxide nanosheets to deliver ultrathin reduced graphene oxide (rGO) layers. The COF-decorated substrates provide a hydrophilic surface with reduced pores and roughness, facilitating the formation of ultrathin rGO layers with ordered stacking patterns and reduced microporous defects. Consequently, the obtained rGO/COF composite membranes can reject ∼90% of Na 2 SO 4 , ∼50% of NaCl, and >98% of various organic dyes, which are higher than pure rGO membranes. Meanwhile, the rGO/COF composite membranes can maintain good stability in solutions with different pH values and salt concentrations, and can be long-term operated for at least 10 days. This work is expected to deepen the understanding of the structure of laminar membranes and provides new perspectives to design ordered laminar membranes.
研究领域:
材料科学
·
环境工程
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
·
IF 8.4
Yun-Han Ren,Wen-Hai Zhang,Ming-Jie Yin,Zhi-Jie Liu,Quan-Fu An
Graphene oxide (GO) membrane has been considered as a promising approach for harvesting pure water from various wastewater to deal with the current water shortage issue, arising from its distinctive 2D channel features. However, the narrow interlayer distance (0.75 Å) of GO nanosheets hampers the utilization of GO membranes for dye wastewater treatment, which demands superior water permeance, high dyes rejection, and low salts rejection. Herein, an in-situ anchored nanoparticle strategy is designed to fabricate Fe(OH) 3 @GO membrane to enlarge the interlayer distance via the uniform distributed Fe(OH) 3 nanoparticles. Benefiting from the in-situ transformation of Fe 3+ into positively charged Fe(OH) 3 nanoparticles, the interlayer distance of GO membranes can be tailored via changing the Fe: GO mass ratio and hydrolysis time. The optimized Fe(OH) 3 @GO membrane realizes a superior water permeance of ∼90.9 LMH/bar (∼19-fold enhancement compared with GO membranes), with >99% and <4% rejection to Evans blue (EB) and NaCl, respectively. Thus, the membrane can be applied for dye desalination and can be stably running for 85 h. Considering the facile and efficient 2D channel tunability, our strategy provides an innovative approach for construction of high-performance 2D membranes.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2017
·Vol. 5
·期 17
·8051-8061
·
IF 8.867
Lei Wang,Xinghua Guo,Kecheng Cao,Bo Li,Yang Li,Meicheng Zhang,Rui Wen,Xing Li,Shoujian Li,Lijian Ma
It has been a major challenge for separation science to separate selectively valuable metal ions from multi-cation aqueous solutions, especially in highly acidic media. In this study, a novel nanodiamond-pillared graphene oxide (NPG) membrane was, for the first time, prepared via intercalation of nanodiamond (ND) into graphene oxide (GO) by using a simple vacuum-assisted self-assembly method. Comprehensive characterization and comparison of GO and its derivative membranes show that after intercalation of ND into GO, the interlayer space and intrastratal nanochannels (similar to “the number of theoretical plates” in chromatography) are markedly increased; the channel-size distribution is profitably narrowed, and the thermal stability and hydrophilicity are enhanced; distinctively, the surface microroughness is significantly improved. The results of ion-sieving experiments demonstrate that the NPG nanofiltration membrane possesses a precise charge-discriminated group separation ability in a strong acidic solution containing 10 coexisting cations. Compared with the unmodified GO membrane, the average filtration rates of the NPG membrane were improved by 76.8% (for monovalent ions), 63.5% (for divalent ions), 118.0% (for trivalent lanthanide ions), 71.0% (for UO22+) and 105.1% (for Th4+) respectively, under the same conditions, meanwhile, the permeation rate of the multivalent cations with same charges shows much better consistency. It’s worth mentioning that UO22+ has the largest hydrated diameter among the cations used in this work, but the filtration rate of UO22+ is actually similar to that of the trivalent lanthanide cations, which may be attributed to the effective charge near +3 of UO22+, as reported in the literature. Finally, the reusability of the as-prepared nanofiltration membrane was investigated in 4 M nitric acid solution. After 5 runs of recycling tests, the group separation ability of the NPG membrane was basically maintained, and the filtration rate was reduced by up to 15.2% (for K+). These findings suggest that the as-prepared carbonaceous nanofiltration membrane could be among the most attractive membrane materials for the separation of valuable metal ions and have great potential applications in not only the nuclear power industry, but also the metallurgical, chemical manufacturing, electroplating and metal finishing industries.
研究领域:
材料科学
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环境科学
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化学工程
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DOI
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 69
·39769-39776
·
IF 2.936
Yang Puheng,Wang Wenxu,Zhang Xiaoliang,Li Honglei,Zhang Shichao,Xing Yalan
Lithium-rich transition-metal layered oxides (LROs), such as Li1.2Mn0.6Ni0.2O2, are promising cathode materials for application in Li-ion batteries, but the low initial coulombic efficiency, severe voltage fade and poor rate performance of the LROs restrict their commercial application. Herein, a self-standing Li1.2Mn0.6Ni0.2O2/graphene membrane was synthesized as a binder-free cathode for Li-ion batteries. Integrating the graphene membrane with Li1.2Mn0.6Ni0.2O2 forming a Li1.2Mn0.6Ni0.2O2/graphene structure significantly increases the surface areas and pore volumes of the cathode, as well as the reversibility of oxygen redox during the charge–discharge process. The initial discharge capacity of the Li1.2Mn0.6Ni0.2O2/graphene membrane is ∼270 mA h g−1 (∼240 mA h g−1 for Li1.2Mn0.6Ni0.2O2) and its initial coulombic efficiency is 90% (72% for Li1.2Mn0.6Ni0.2O2) at a current density of 40 mA g−1. The capacity retention of the Li1.2Mn0.6Ni0.2O2/graphene membrane remains at 88% at 40 mA g−1 after 80 cycles, and the rate performance is largely improved compared with that of the pristine Li1.2Mn0.6Ni0.2O2. The improved performance of the Li1.2Mn0.6Ni0.2O2/graphene membrane is ascribed to the lower charge-transfer resistance and solid electrolyte interphase resistance of the Li1.2Mn0.6Ni0.2O2/graphene membrane compared to that of Li1.2Mn0.6Ni0.2O2. Moreover, the lithium ion diffusion of the Li1.2Mn0.6Ni0.2O2/graphene membrane is enhanced by three orders of magnitude compared to that of Li1.2Mn0.6Ni0.2O2. This work may provide a new avenue to improve the electrochemical performance of LROs through tuning the oxygen redox progress during cycling.
研究领域:
材料科学
·
电化学
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DOI
PubMed
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2024
·
IF 5.5
Ziyi Huang,Xiaojia Zhang,Fan Yang,Rajkumar Devasenathipathy,Xinglan Peng,Limin Wang,Dujuan Huang,Youjun Fan,Wei Chen,Du-Hong Chen
Background As a hydrophilic two-dimensional material with oxygen-containing groups on its basal planes, graphene oxide (GO) has been used for the fabrication of GO-based membranes to purify/desalinate water. However, promoting salt rejection of GO-based membranes is challenging while maintaining high water permeability. Methods First, the mercaptoethylamine-modified Ag NWs (Ag-MA) were prepared by mixing Ag NWs and MA to form Ag—S bonds. Then, Ag-MA was deposited on the GO membrane under externally assisted filtration to achieve the GO/Ag-MA membrane, which ensures the well-stacking of GO sheets and the even coating of GO membrane. Therefore, the delicately fabricated membrane possesses great electropositive cations and high swelling-tolerance in water solution. Significant findings We found that a high electrostatic repulsive interaction between the amino group and metal cations in GO/Ag-MA membrane aided the promotion of rejection rates, which was up to 75 % for both K + and Mg 2+ , surpassing that of the previously reported values. This work highlights a new approach for enhancing the electrostatic repulsion with metal cations near the surface/interface of GO-based membranes and their application in the development of water desalination and purification.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2024
·
IF 8.2
Yu Qiang,Siyan Gao,Mengjiao Wu,Xiaoling Lei,Haiping Fang
Traditional mining practices not only cause severe environmental issues , but also face the problem of insufficient production capacity of gold to meet its growing demand. The proposed alternative strategies for gold production, such as the extraction of gold from seawater , still keep a formidable challenge due to their strong dependence on adsorbent materials with high capacity, selectivity , and sensitivity, while also needing to meet the demands of being environmentally friendly and cost-effective. In practice, the direct extraction of gold from seawater is limited by its extremely low yield and high energy expenditure. However, if the combination of gold extraction techniques with seawater desalination can substantially reduce the energy consumption, the extraction of gold from seawater will become economical and feasible. In this paper, we evaluate the feasibility of marine gold extraction using reduced graphene oxide membranes (rGOM) during the seawater desalination process . The rGOM can adsorb almost all Au 3+ from the solutions with trace concentrations of Au 3+ ranging from 10 ppb to 200 ppb. The adsorption quantity is linearly related to the concentration, indicating that the adsorption capacity of rGOM is much higher than the total amount of Au 3+ in the solution. Additionally, the rGOM can selectively adsorb 99 % of Au 3+ in the mixed solution while hardly adsorbing other common elements in seawater. More importantly, the rGOM exhibits the long-term stability over 30 days when being immersed in the solution, making it directly compatible with the existing seawater desalination processes. These specific properties allow the rGOM to be an ideal candidate for combining the extraction of gold from seawater with seawater desalination processes. Our findings provide a methodology for enhancing the economic efficiency of the extraction of gold from seawater and hold promise for addressing the problem of gold scarcity.
研究领域:
环境科学
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材料科学
·
海洋学
✓ 已验证
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2024
·
IF 10.8
Qian Xiao,Zhe Yang,Wanbin Li,Bo Wei,Hao Guo,Shuili Yu,Qimao Gan,Wenyu Liu,Chuyang Y. Tang
Advanced reduction processes (ARPs) are promising for pollutant removal in drinking water treatment. In this study, we demonstrated highly efficient reduction of bromate, a harmful disinfection byproduct, by coupling ARPs with an iron nanoparticles-intercalated graphene oxide (GO@FeNPs) catalytic membrane. In the presence of 1.0 mM sulfite (S(IV)), the GO@FeNPs membrane/S(IV) system achieved nearly complete removal of 80 μg/L bromate in 3 min. The first-order reaction rate constant for bromate removal in this system was 420 ± 42 min–1, up to 5 orders of magnitude faster than previously reported ARPs. The GO@FeNPs catalytic membrane may offer potential advantages of nanoconfinement and facilitated electron shuttling in addition to the high surface area of the fine FeNPs, leading to the remarkable ARP performance. The GO@FeNPs membrane showed excellent stability, maintaining >97.0% bromate removal over 20 cycles of repeated runs. The membrane can also be applied for fast catalytic reduction of other oxyanions, showing >98.0% removal of nitrate and chlorate. This work may present a viable option for utilizing high-performance reductive catalytic membranes for water decontamination.
研究领域:
环境科学
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材料科学
·
水处理技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Advanced Electronic Materials
·
2023
·Vol. 9
·期 5
·2201241
·
IF 6.2
Bingquan Peng,Quan Zhang,Yueyu Zhang,Yimin Zhao,Shengyue Hou,Yizhou Yang,Fangfang Dai,Ruobing Yi,Ruoyang Chen,Jun Wang,Lei Zhang,Liang Chen,Shengli Zhang,Haiping Fang
2D materials are promising nanomaterials for future applications due to their predominant quantum effects and unique properties in optics, electrics, magnetics, and mechanics. However, explorations in unique properties and potential applications of novel 2D materials have been hampered by synthesis and their stability under ambient conditions. Recently, in the graphene, 2D β-CuI is observed experimentally under ambient conditions. Here, it is shown that this 2D β-CuI@graphene possesses unexpected piezoresistive effect and room-temperature ferromagnetism. Moreover, this 2D β-CuI crystal is likely to be stable in a wide range of temperature, that is, below 900 K. Theoretical studies reveal that the unexpected piezoresistive effect is mainly attributable to the convergence of the electrons on Cu and I atoms to the Fermi level with increasing strain. There is a magnetic moment that is ≈0.97 μ B on the edge of β-CuI nanocrystal created by an iodine vacancy, which is considered the origin of such strong room-temperature ferromagnetism. Clearly, the 2D β-CuI@graphene provides a promising nanomaterial in the nano-sensors with low power consumption pressure and magnetic nano-devices with a size down to atomic scale. The discovery in the present work will evoke various new 2D nanomaterials with novel properties in nanotechnology, biotechnology, sensor materials, and technologies.
研究领域:
材料科学
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纳米技术
·
物理学
✓ 已验证
DOI
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-12
·
IF 15.7
Dai Ziwen,Jin Pengrui,Yuan Shushan,Yang Jiakuan,Agrawal Kumar Varoon,Wang Huanting
Atomically thin graphene membranes with sub-1-nm pores show promise for ion/molecular separation, osmotic energy generation, and energy storage. Narrowing the pore size distribution and controlling the surface charge are essential to achieve these applications. However, nanoporous graphene membranes fabricated via conventional methods possess a broad pore size distribution and inadequately regulated surface charge, limiting their applications. Herein, we present a molecular anchoring approach for scalable synthesis of nanoporous graphene membranes via a bottom-up technique, aiming to narrow the pore size distribution without reducing the pore density while simultaneously adjusting the charge properties of nanopores. By selecting suitable anchoring molecules, the custom-tailored pore size distribution and chemical functionality of nanoporous graphene membranes can be achieved. Leveraging the steric restriction effect, anchoring monomers selectively traverse larger nanopores to form ion-selective plugs, effectively repairing these nanopores. The centimeter-scale nanoporous graphene membrane with an ion-selective plug achieves high separation selectivity (K + /Na + =20, K + /Mg 2+ =330). Theoretical simulations indicate that a smaller pore size, narrow pore size distribution, and positive charge result in a larger energy barrier difference, leading to ultrahigh metal ion selectivity. Furthermore, in treating lithium battery leaching solutions, Li + /divalent ions selectivity exceeds 900. These findings provide a way for designing graphene-based membranes.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials
·
2020
·Vol. 14
·期 1
·146
·
IF 3.057
Yangjinghua Yu,Zhong Wang,Runjun Sun,Zhihua Chen,Meicheng Liu,Xiang Zhou,Mu Yao,Guohe Wang
Graphene stratiform membrane materials have been recently applied to heavy metal removal in aqueous systems via adsorption due to their high mechanical strength, chemical stability, and other properties. We applied reduced graphene oxide (rGO) alone as an adsorbent to remove heavy metal ions from wastewater. Self-supported rGO membrane was prepared using a green reduction method with sodium hydrosulfite. We used the Raman spectra to observe the structure of the rGO membrane. The morphology of the self-supported membrane was measured by a scanning electron microscope. The Cu2+adsorption performance was measured in terms of pH, reaction time, metal ion concentration, and temperature. The maximum Cu2+adsorption capacity of the rGO membrane was found to be 149.25 mg/g. The adsorption process followed a pseudo-second-order kinetic model, and adsorption isotherms were simulated by the Freundlich model.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Boya Wang,Cheng Chen,Wei Yu,Jiujing Xu,Bisheng Li,Leihong Zhao,Liguo Shen,Hongjun Lin
Despite their considerable promise in water treatment, two-dimensional graphene oxide (GO) membranes are still hindered by inadequate structural stability due to weak interlayer interactions and structural defects, along with low permeability due to limited surface water inlets. Here, inspired by the leaf structure of Tillandsia, a stable and ultrapermeable GO-based membrane with Wenzel model hydrophilic surface and robust interior nanochannels was fabricated through interlayer molecular bridge and in-situ growth of covalent organic framework (COF, TP-TTTA) nanocrystals. The incorporation of amine monomer (4,4′,4″-(1,3, 5-triazine-2,4,6-triyl)trianiline, TTTA) molecular bridges for covalent crosslinking of GO nanosheets effectively stabilized the membrane framework. The obtained GO@TP-TTTA membrane resisted structural disassembly under prolonged acidic/alkaline immersion and high-pressure conditions. The in-situ growth of TP-TTTA COF led to a rough membrane surface with numerous selective and hydrophilic inlets. Thus, the water permeability of the obtained GO@TP-TTTA membrane could reach up to 246.9 L·m −2 ·h −1 ·bar −1 –2.6 times larger than that of pristine GO membrane–along with a retained 98.3 % rejection rate for bright blue G (BBG), successfully overcoming the common permeability-selectivity trade-off. Moreover, the resultant membrane demonstrated superior anti-fouling properties than the pure GO membrane. This molecular-scale structural design offers a novel approach for high-performance GO-based membranes, with promising applications in wastewater treatment.
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产品关联
DOI
高影响因子
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