Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
EPSRC "Frontier Engineering" Centre for Nature Inspired Engineering & Department of Chemical Engineering, University College London, London, WC1E 7JE, UK.
Chem Soc Rev. 2021 Nov 1;50(21):11747-11765. doi: 10.1039/d1cs00737h.
Tremendous progress in two-dimensional (2D) nanomaterial chemistry affords abundant opportunities for the sustainable development of membranes and membrane processes. In this review, we propose the concept of mixed dimensional membranes (MDMs), which are fabricated through the integration of 2D materials with nanomaterials of different dimensionality and chemistry. Complementing mixed matrix membranes or hybrid membranes, MDMs stimulate different conceptual thinking about designing advanced membranes from the angle of the dimensions of the building blocks as well as the final structures, including the nanochannels and the bulk structures. In this review, we survey MDMs (denoted D/2D, where is 0, 1 or 3) in terms of the dimensions of membrane-forming nanomaterials, as well as their fabrication methods. Subsequently, we highlight three kinds of nanochannels, which are 1D nanochannels within 1D/2D membranes, 2D nanochannels within 0D/2D membranes, and 3D nanochannels within 3D/2D membranes. Strategies to tune the physical and chemical microenvironments of the nanochannels as well as the bulk structures based on the size, type, structure and chemical character of nanomaterials are discussed. Some representative applications of MDMs are illustrated for gas molecular separations, liquid molecular separations, ionic separations and oil/water separation. Finally, current challenges and a future perspective on MDMs are presented.
二维（2D）纳米材料化学的巨大进展为膜和膜过程的可持续发展提供了丰富的机会。在这篇综述中，我们提出了混合维度膜（MDM）的概念，它是通过将 2D 材料与不同维度和化学性质的纳米材料集成制造而成的。与混合基质膜或杂化膜不同，MDM 从构建块的维度以及最终结构（包括纳米通道和体相结构）的角度激发了关于设计先进膜的不同概念性思维。在这篇综述中，我们根据成膜纳米材料的维度以及它们的制造方法来综述 MDM（表示为 D/2D，其中 为 0、1 或 3）。随后，我们重点介绍了三种纳米通道，即 1D/2D 膜中的 1D 纳米通道、0D/2D 膜中的 2D 纳米通道和 3D/2D 膜中的 3D 纳米通道。讨论了基于纳米材料的尺寸、类型、结构和化学性质来调节纳米通道和体相结构的物理和化学微环境的策略。还举例说明了 MDM 在气体分子分离、液体分子分离、离子分离和油水分离方面的一些代表性应用。最后，提出了 MDM 当前面临的挑战和未来展望。
