Robust conjugated two- (2D) and three-dimensional (3D) non-metallic network polymers have attracted immense interest due to their unusual electronic, optoelectronic, magnetic and electrocatalytic properties. In addition, their tunable structures and properties promise to offer many opportunities in various applications. However, even after years of intensive exploration in science and technology, facile and scalable methods capable of producing fused-aromatic based stable non-metallic network polymers with uniformly decorated heteroatoms with/without holes remain limited. To overcome these issues, stable organic network polymers have been designed and synthesized. They have uniformly distributed heteroatoms,1 holes with heteroatoms2 and transition metal nanoparticles in the holes.3 Their network structures were confirmed using various characterization techniques, including scanning tunneling microscopy (STM, Figure 1). Based on the stoichiometry of 2D layered network polymers, they were, respectively, designated C2N, C3N, C4N, and M@C2N (M = Co, Ni, Pd, Pt, Ru). Their electronic and electrical properties were evaluated by electrooptical and electrochemical measurements along with density-functional theory (DFT) calculations. Furthermore, robust 3D cage-like organic network polymers have also been constructed and they show high sorption properties.4,5 The results suggest that these newly-developed 2D and 3D organic network polymers offer greater opportunities, from wet-chemistry to various device applications.
 Mahmood, et al. Two-dimensional polyaniline (C3N) from carbonized organic single crystals. Proceedings of National Academy of Sciences, USA 2016, 113, 7414.
 Mahmood, et al. Nitrogenated holey two-dimensional structure. Nature Communications 2015, 6, 6486.
 Mahmood, et al. An efficient and pH-universal ruthenium-based catalyst for the hydrogen evolution reaction. Nature Nanotechnology 2017, 12, 441.
 Bae, et al. Forming a three-dimensional porous organic network via explosion of organic single crystals in solid-state. Nature Communications 2017, 8, 159-Highlighted in Nature Nanotechnology 2018, 13, 4.
 Mahmood, et al. A robust 3D cage-like ultramicroporous network structure with high gas uptake capacities. Angewandte Chemie International Edition 2018, 57, 3415.
Figure 1. STM images: A, C3N; B, C2N. C, Schematic representation of Ru@C2N.