Article
Chemistry, Physical
Chengzhen Sun, Kailin Luo, Runfeng Zhou, Bofeng Bai
Summary: The theoretical model accurately predicts the surface molecular permeation through two-dimensional graphene nanopores, especially for strongly adsorbed molecules. It is competent in describing both the overall permeation flux and detailed density distribution.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Chengzhen Sun, Qiyuan Wang, Keteng Tang, Dong Wei, Bofeng Bai
Summary: Graphene nanopore-based two-dimensional membranes show great promise for gas separation. However, the potential of porous graphene membranes for alkane separations remains underutilized due to the complex effects of molecular chain length on permeation. Through molecular dynamics simulation, we demonstrate that hydrocarbon molecules of different chain lengths exhibit nearly identical permeation behavior through graphene nanopores of varying sizes. This undifferentiated permeation is influenced by factors such as penetration rate, permeation time, molecular incident angle, and density within the pore. Furthermore, we propose a molecular-orientation sieving effect as a means of selectively separating alkanes through graphene nanopores, based on the varying difficulty of hydrocarbon molecules in achieving an upright orientation within the pores.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Engineering, Chemical
Shiqi Huang, Shaoxian Li, Kuang-Jung Hsu, Luis Francisco Villalobos, Kumar Varoon Agrawal
Summary: Etching an ensemble of nanopores in single-layer graphene using a millisecond gasification reactor (MGR) allows for high-performance gas sieving; Analysis of etching conditions on nanopore formation using Raman spectroscopy and scanning tunneling microscope reveals the relationship between etching temperature and pore density; Optimized nanoporous single-layer graphene membranes show extremely attractive CO2 sieving performances with high CO2 permeance and selectivity.
JOURNAL OF MEMBRANE SCIENCE
(2021)
Article
Multidisciplinary Sciences
Shiqi Huang, Shaoxian Li, Luis Francisco Villalobos, Mostapha Dakhchoune, Marina Micari, Deepu J. Babu, Mohammad Tohidi Vahdat, Mounir Mensi, Emad Oveisi, Kumar Varoon Agrawal
Summary: This study reports a millisecond carbon gasification chemistry that incorporates high density of oxygen clusters, evolving into CO2-sieving vacancy defects under controlled and predictable gasification conditions. A statistical distribution of nanopore lattice isomers is observed, and the technique is scalable.
Article
Chemistry, Multidisciplinary
Shuming Zeng, Tian Wang, Yuanbin Zhang, Bruce G. Elmegreen, Binquan Luan, Zonglin Gu
Summary: In this study, we demonstrate the unprecedented separation efficiency of CO2/C2H2 using a graphene membrane embedded with crown ether nanopores. Through molecular dynamics simulation and density functional theory, we found that the electrostatic gas-pore interaction allows fast transport of CO2 while completely prohibiting C2H2 transport, resulting in remarkable permeation selectivity. Our findings show the potential application of graphene crown pores for CO2 separation with outstanding performance.
Article
Chemistry, Multidisciplinary
Binquan Luan, Bruce Elmegreen, Marcelo A. Kuroda, Zonglin Gu, Guojun Lin, Shuming Zeng
Summary: With the growing concerns about global warming, it has become urgent to capture carbon dioxide from various sources. Recent research shows that crown nanopores embedded in graphene can efficiently allow CO2 to pass while blocking other flue gas components.
Article
Green & Sustainable Science & Technology
Guozhao Ji, Xian Yin, Weng Fu, Xiaonan Kou, Dachamir Hotza, Yinxiang Wang, Aimin Li, Gianni Olguin, Weijian Wang
Summary: This study aimed to improve the hydrothermal stability of silica membrane by doping cobalt in silica membrane precursors. A cobalt-doped silica membrane with a cobalt/silicon ratio of 1/4 was fabricated. The membrane exhibited good helium permeance and selectivity at 500℃. It was then used for methane steam reforming, which resulted in increased methane conversion and hydrogen production.
JOURNAL OF CLEANER PRODUCTION
(2023)
Article
Chemistry, Physical
Peng Lin, Yinggan Zhang, Xiaolin Tan, Rui Xiong, Baisheng Sa, Qilang Lin
Summary: This study introduces a simple and efficient method to synthesize graphene nanosheets from coal-tar pitch, which has been validated through both experimental and theoretical approaches. The research reveals the microscopic origin of Al4C3 decomposition and the occurrence of chemical etching process.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Energy & Fuels
Wei Li, Kang Yang, Dong Deng, Changxin Zhao, Shilong Yang, Yuanping Cheng, Shouqing Lu
Summary: Gas flow in coal is complex and influenced by multiple mechanisms and pore structures. Understanding gas flow behavior in coal is crucial for predicting coalbed methane production and preventing gas-induced disasters in coal mines. This study uses the lattice Boltzmann method to construct a model that considers surface adsorption and diffusion effects, revealing various flow mechanisms including viscous flow, enhanced gas slippage, and surface diffusion.
Article
Chemistry, Multidisciplinary
Wan-Chi Lee, Anshaj Ronghe, Luis Francisco Villalobos, Shiqi Huang, Mostapha Dakhchoune, Mounir Mensi, Kuang-Jung Hsu, K. Ganapathy Ayappa, Kumar Varoon Agrawal
Summary: This study demonstrates that placing angstrom-sized oxygen-functionalized graphene nanopores at the liquid-vapor interface can greatly enhance water evaporation rates. The presence of these nanopores decreases the free energy barrier for water evaporation and increases the rotational and translational dynamics of water molecules, leading to a significant increase in evaporation flux. These findings have potential applications in energy-efficient technologies relying on water evaporation.
Article
Chemistry, Multidisciplinary
Archith Rayabharam, Haoran Qu, YuHuang Wang, N. R. Aluru
Summary: The study demonstrates that nanosized pores with controlled pore sizes can separate ethanol-water mixtures through molecular sieving at room temperature and pressure, eliminating the need for energy-intensive and expensive distillation. A selectivity ratio as high as 6700 for water/ethanol separation was achieved with a (6,4) nanotube, which diminishes as the pore size increases beyond 0.306 nm.
Article
Chemistry, Multidisciplinary
Tobias Foller, Lukas Madauss, Dali Ji, Xiaojun Ren, K. Kanishka H. De Silva, Tiziana Musso, Masamichi Yoshimura, Henning Lebius, Abdenacer Benyagoub, Priyank V. Kumar, Marika Schleberger, Rakesh Joshi
Summary: Research shows that high-density in-plane pores in graphene oxide membranes do not necessarily result in higher water permeability. Membranes with high in-plane pore density but low oxygen functionalities may completely block water, but exhibit enhanced permeation when using water-ethanol mixtures.
Article
Engineering, Environmental
Leila Dehdari, Penny Xiao, Kevin Gang Li, Ranjeet Singh, Paul A. Webley
Summary: One option for economical storage and transportation of hydrogen is to add it to the existing natural gas pipelines. This study experimentally assesses the production of high purity hydrogen and/or natural gas products using vacuum swing adsorption process at low pressure terminals.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Energy & Fuels
Gizem Nur Bulanik Durmus, C. Ozgur Colpan, Yilser Devrim
Summary: In this study, the purification of hydrogen from a H-2:CO2:CO mixture using a high-temperature electrochemical purification system was investigated. It was found that the operating temperature had the greatest impact on performance, with hydrogen purity reaching 99.999% at 160 degrees C. Gas mixtures containing CO showed better performance at 180 degrees C, while the gas mixture without CO performed best at 160 degrees C.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Energy & Fuels
Yuxin Yan, Ying Qi, Marc Marshall, W. Roy Jackson, Andrew Stanger, Quang Anh Tran, Rohan Stanger, Alan L. Chaffee
Summary: The study utilizes a mineral-separation process to produce density fractions of low-rank coals with varying maceral group proportions for analysis of their physical and chemical properties. The findings aim to suggest new ways of utilizing the vast Victorian brown coal resource.
Article
Chemistry, Physical
Xuan Sun, Weiwei Chen, Lijun Liang, Wei Hu, Huanhuan Wang, Zhenfeng Pang, Yuxun Ye, Xiurong Hu, Qi Wang, Xueqian Kong, Yizheng Jin, Ming Lei
CHEMISTRY OF MATERIALS
(2016)
Article
Energy & Fuels
Baojian Liu, Yong Peng, Qu Chen
Article
Thermodynamics
Mahinder Ramdin, Sayee Prasaad Balaji, Jose Manuel Vicent-Luna, Ariana Torres-Knoop, Qu Chen, David Dubbeldam, Sofia Calero, Theo W. de Loos, Thijs J. H. Vlugt
FLUID PHASE EQUILIBRIA
(2016)
Article
Chemistry, Physical
Wenhui Zhong, Jinxia Liang, Wei Hu, Xinrui Cao, Chuanyi Jia, Jun Jiang
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2016)
Article
Multidisciplinary Sciences
Lijun Liang, Wei Hu, Zhisen Zhang, Jia-Wei Shen
SCIENTIFIC REPORTS
(2016)
Review
Chemistry, Multidisciplinary
Wei Hu, Sai Duan, Yi Luo
WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE
(2017)
Article
Computer Science, Interdisciplinary Applications
Mahinder Ramdin, Qu Chen, Sayee Prasaad Balaji, Jose Manuel Vicent-Luna, Ariana Torres-Knoop, David Dubbeldam, Sofia Calero, Theo W. de Loos, Thijs J. H. Vlugt
JOURNAL OF COMPUTATIONAL SCIENCE
(2016)
Article
Chemistry, Organic
Xiaoyu Han, Can Ye, Fenfen Chen, Qu Chen, Yongjiang Wang, Xiaofei Zeng
ORGANIC & BIOMOLECULAR CHEMISTRY
(2017)
Article
Chemistry, Multidisciplinary
Cai Yao, Zhengzhong Kang, Bin Yu, Qu Chen, Yingchun Liu, Qi Wang
Article
Chemistry, Physical
Lijun Liang, Hanxing Zhou, Jia-chen Li, Qu Chen, Linli Zhu, Hao Ren
Summary: This study utilized machine learning techniques to analyze the impact of pore shape, pore area, and applied pressure on salt rejection and water permeation in the desalination process. Physical-chemical analysis revealed the key factors affecting these processes. Based on the findings, a graphene pore with a specific shape was designed to achieve high water permeation and salt rejection.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Multidisciplinary
Qu Chen, Lijun Liang, Zhisen Zhang, Qi Wang
Summary: This study found that the successful release of protein/peptide molecules from CNTs depends on the pore width, pore length, and net charges on the peptide, with external electric fields assisting in overcoming potential well barriers. Peptides with more net charges are more likely to be released effectively through the use of electric fields.
Article
Nanoscience & Nanotechnology
Qu Chen, Jianping Zhou
Summary: In this study, molecular dynamics simulations were used to investigate the self-diffusion of fluids in one-dimensional nanopores. The results show that the Bosanquet equation can predict the self-diffusivities of gases in carbon nanotubes but with poor accuracy. The deviations are mainly due to the limited accuracy of the free path model and the underestimation of diffusivity in nanotubes by the Knudsen model. The presence of hydrogen bonding in water violates the mean free path theory, leading to the failure of the Bosanquet equation in predicting its self-diffusivity.
Article
Chemistry, Physical
Qu Chen, Mahinder Ramdin, Thijs J. H. Vlugt
Summary: Several physical solvents, such as methanol, poly(ethylene glycol) dimethyl ethers, n-methyl-2-pyrrolidone, and propylene carbonate, can be used for the removal of acid gas impurities from synthesis gas or natural gas. Monte Carlo simulations in the osmotic ensemble accurately predict the gas solubility trend in these solvents, and the predicted Henry coefficients are in good agreement with experimental results. The solubility of gases in these solvents follows the order: H2S > CO2 > C2H6 > CH4 > CO > N-2 > H-2.
MOLECULAR SIMULATION
(2023)
Article
Chemistry, Physical
Yujin Zhang, Wei Hu
Article
Chemistry, Physical
Yujin Zhang, Wei Hu, Liyun Zhao, Jiancai Leng, Hong Ma