Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States.
James Franck Institute, University of Chicago, Chicago, Illinois 60637, United States.
J Am Chem Soc. 2023 Mar 8;145(9):5261-5269. doi: 10.1021/jacs.2c12853. Epub 2023 Feb 27.
Generating electricity from a salinity gradient, known as osmotic power, provides a sustainable energy source, but it requires precise nanoscale control of membranes for maximum performance. Here, we report an ultrathin membrane, where molecule-specific short-range interactions enable giant gateable osmotic power with a record high power density (2 kW/m for 1 M∥1 mM KCl). Our membranes are charge-neutral two-dimensional polymers synthesized from molecular building blocks and operate in a Goldilocks regime that simultaneously maintains high ionic conductivity and permselectivity. Molecular dynamics simulations quantitatively confirm that the functionalized nanopores are small enough for high selectivity through short-range ion-membrane interactions and large enough for fast cross-membrane transport. The short-range mechanism further enables reversible gateable operation, as demonstrated by polarity switching of osmotic power with additional gating ions.
从盐度梯度中发电，即渗透能，提供了一种可持续的能源，但它需要对膜进行精确的纳米级控制，以实现最大性能。在这里，我们报告了一种超薄膜，其中分子特异性短程相互作用使渗透能具有巨大的可调节性，创下了记录的高功率密度（1 M∥1 mM KCl 时为 2 kW/m）。我们的膜是由分子构建块合成的电荷中性二维聚合物，其工作在一个同时保持高离子电导率和选择性的“金发姑娘”区域。分子动力学模拟定量证实，功能化纳米孔足够小，通过短程离子-膜相互作用实现高选择性，同时又足够大，实现快速跨膜传输。短程机制进一步实现了可调节的可逆操作，如通过外加门控离子实现渗透能的极性转换。
