Polyphenylene superhoneycomb network (PSN) and covalent triazine framework (CTF) are experimentally realized periodically porous graphene derivatives. Such ultrathin layers with homogeneously distributed pores of controllable sizes are highly desirable for applications in molecular separations such as water purification. The permeation energy barrier is expected to be a function of not only the pore size, but also the specific permeation trajectory as determined by hydrogen bonding interactions at the water-pore interface.

Here, we report a detailed first-principles study of permeation of a single H₂O molecule through a monolayer PSN and CTF-0, as well as its diffusion behavior inside a bilayer PSN. The calculated energy barrier of 1.44 eV indicates the infeasibility of using PSN as a water permeation membrane. However, the barrier decreases considerably to 0.94 eV when three C-H pairs at the pore are replaced with N atoms into CTF-0. Inside a bilayer PSN, we find facile interlayer sliding as well as interlayer expansion owing to out-of-plane reorientation of the H₂O molecule. In all cases, the functional groups at the pore significantly alter the orientation of the H₂O molecule and the corresponding barriers. Such atomistic insights at the porous interface would provide a valuable guidance in advancing rational pore design principles.

聚苯撑超蜂窝网络（PSN）和共价三嗪骨架（CTF）是通过实验实现的周期性多孔石墨烯衍生物。这种具有均匀分布的，可控制大小的孔的超薄层对于分子分离例如水净化中的应用是非常需要的。渗透能垒预计不仅是孔径的函数，而且是由水-孔界面处的氢键相互作用确定的特定渗透轨迹的函数。

在这里，我们报告详细的第一原理研究的单个H ₂ O分子渗透通过单层PSN和CTF-0，以及其在双层PSN内的扩散行为。计算得出的1.44 eV的能垒表明使用PSN作为透水膜是不可行的。但是，当孔中的三个CH对被N原子取代成CTF-0时，势垒大大降低至0.94 eV。在双层PSN内，我们发现由于H ₂ O分子的面外重新定向，层间滑动容易，层间膨胀也很容易。在所有情况下，孔中的官能团都会显着改变H ₂的方向O分子和相应的屏障。多孔界面上的这种原子学见解将为推进合理的孔设计原理提供有价值的指导。