团队博士刘亦琳关于纳米复合膜水蒸气输运特性的机理研究发表于老牌理科期刊Physical Chemistry Chemical Physics （PCCP），并且被选为该期刊24卷27期封面论文。

Dr. Liu Yilin published a paper titled “Molecular simulation of enhanced separation of humid air components using GO-PVA nanocomposite membranes under differential pressures” in Physical Chemistry Chemical Physics. And the study was selected as the cover paper of the journal (Vol. 24 No. 27, 21 July 2022, p. 16399-16924).

亲水纳米复合膜在空气除湿的核心过程——水蒸气分离方面具有显著的优势。本文着重探讨氧化石墨烯-聚乙烯醇（GO-PVA）纳米复合膜强化水蒸气分离的微观机理。采用分子动力学（MD）和蒙特卡罗（MC）方法研究了水蒸气和氮气在氧化石墨烯-聚乙烯醇膜的吸附和扩散行为。研究表明，将氧化石墨烯（GO）嵌入聚乙烯醇基质（PVA）可以提高玻璃化转变温度和自由体积分数。聚合物链与氧化石墨烯纳米颗粒的相互作用，显著提高了复合膜对水蒸气的吸附能力，抑制了氮气在膜中的吸附。GO-PVA-0.5膜的水蒸气透过率为8844.07 Barrer，分离系数为3.53。本研究可为气体分离膜的优化与合成提供支撑。

Hydrophilic nanocomposite membranes have significant advantages in the separation of water vapor which is the core process of air dehumidification. This paper focuses on exploring the micro-mechanism of enhanced separation by graphene oxide - polyvinyl alcohol (GO-PVA) nanocomposite membranes. The sorption and diffusion behaviors of water vapor and nitrogen in GO-PVA membranes were investigated using Molecular Dynamics (MD) and Monte Carlo (MC) methods. The study showed that embedding GO into PVA matrix results in higher glass transition temperature and fractional free volume. The latter is believed to enhance the diffusivity of gas molecules in polymeric membranes. The interaction between polymer chains and GO nanoparticles notably promotes the adsorption capacity of water vapor and inhibits the nitrogen adsorption in the membrane. A water vapor permeance of 8844.07 Barrer and a separation factor of 3.53 could be achieved by GO-PVA-0.5 membrane. The analysis confirmed that GO has the same effect on single gas and binary gas mixtures, i.e., increasing water vapor permeability and selectivity. The calculated water vapor permeance of binary gas is 83% lower than that of single gas permeation. It is expected that this research could provide fundamentals for the optimization and synthesis of gas separation membranes. 

文章链接：http://doi.org/10.1039/d2cp01411d