 This paper presents two new three-dimensional, 3D, covalent organic frameworks, COFs, one based on a rectangular planar topology and the other on a trigonal planar topology. Both structures feature a large pore size of 46a and an extremely low density, making them ideal candidates for use as carbon dioxide adsorbents. Additionally, the rectangular planar COF has a unique feature of being composed entirely of face-enclosed organic polyhedral, while the trigonal planar COF features a precise uniform micropore size of 1 nanometer. These structures expand the range of available 3D COF topologies, providing researchers with additional options when designing these materials. This article was authored by Dongyang Zhu, Yi Fanzhu, Yu Chen, and others.