Wu Keliu, Chen Zhangxin, Li Jing, Xu Jinze, Wang Kun, Wang Shuhua, Dong Xiaohu, Zhu Zhouyuan, Peng Yan, Jia Xinfeng, Li Xiangfang
Department of Chemical and Petroleum Engineering, University of Calgary, Alberta, T2N 1N4, Canada.
School of Petroleum Engineering, China University of Petroleum, Beijing, 102249, China.
Angew Chem Int Ed Engl. 2018 Jul 9;57(28):8432-8437. doi: 10.1002/anie.201712915. Epub 2018 Jun 7.
The manipulation of a nanoconfined fluid flow is a great challenge and is critical in both fundamental research and practical applications. Compared with chemical or biochemical stimulation, the use of temperature as controllable, physical stimulation possesses huge advantages, such as low cost, easy operation, reversibility, and no contamination. We demonstrate an elegant, simple strategy by which temperature stimulation can readily manipulate the nanoconfined water flow by tuning interfacial and viscous resistances. We show that with an increase in temperature, the water fluidity is decreased in hydrophilic nanopores, whereas it is enhanced by at least four orders of magnitude in hydrophobic nanopores, especially in carbon nanotubes with a controlled size and atomically smooth walls. We attribute these opposing trends to a dramatic difference in varying surface wettability that results from a small temperature variation.
纳米受限流体流动的操控是一项巨大挑战，在基础研究和实际应用中都至关重要。与化学或生化刺激相比，利用温度作为可控的物理刺激具有巨大优势，如成本低、操作简便、可逆且无污染。我们展示了一种巧妙、简单的策略，通过调节界面阻力和粘性阻力，温度刺激能够轻松操控纳米受限水流。我们发现，随着温度升高，亲水性纳米孔中的水流动性降低，而在疏水性纳米孔中，尤其是在尺寸可控且壁面原子级光滑的碳纳米管中，水流动性增强了至少四个数量级。我们将这些相反的趋势归因于由微小温度变化导致的表面润湿性的显著差异。
