Osmotic power, also known as ‘blue energy’, is produced by mixing solutions of different salt concentrations, and represents a vast, sustainable and clean energy source. The efficiency of harvesting osmotic power is primarily determined by the transmembrane performance, which is in turn dependent on ion conductivity and selectivity towards positive or negative ions. Atomically or molecularly thin membranes with a uniform pore environment and high pore density are expected to possess an outstanding ion permeability and selectivity, but remain unexplored. Here we demonstrate that covalent organic framework monolayer membranes that feature a well-ordered pore arrangement can achieve an extremely low membrane resistivity and ultrahigh ion conductivity. When used as osmotic power generators, these membranes produce an unprecedented output power density over 200 W m⁻² on mixing the artificial seawater and river water. This work opens up the application of porous monolayer membranes with an atomically precise structure in osmotic power generation.

渗透力，又称“蓝色能源”，是通过混合不同盐浓度的溶液产生的，是一种巨大的、可持续的、清洁的能源。获取渗透力的效率主要取决于跨膜性能，而跨膜性能又取决于离子电导率和对正离子或负离子的选择性。具有均匀孔环境和高孔密度的原子或分子薄膜有望具有出色的离子渗透性和选择性，但仍未得到探索。在这里，我们证明了具有良好有序孔排列的共价有机框架单层膜可以实现极低的膜电阻率和超高的离子电导率。当用作渗透发电机时，^-2混合人工海水和河水。这项工作开辟了具有原子精确结构的多孔单层膜在渗透发电中的应用。