Since the discovery of graphene in 2004, conjugated two-dimensional (2D) 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 more opportunities than graphene in various applications. However, even after years of intensive exploration of 2D materials in science and technology, facile and scalable methods capable of producing stable 2D network polymers with uniformly decorated heteroatoms with/without holes remain limited. To overcome these issues, new layered 2D network polymers have been designed and synthesized. They have uniformly distributed heteroatoms , holes with heteroatoms  and transition metal nanoparticles on the holes . The structures were confirmed by scanning tunneling microscopy (STM) (Figure 1A and 1B). Based on the stoichiometry of the basal plane, they were, respectively, designated C3N, C2N 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. The results suggest that these newly-developed 2D network polymers offer greater opportunities, from wet-chemistry to device applications.

Since the discovery of graphene in 2004, conjugated two-dimensional (2D) 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 more opportunities than graphene in various applications. However, even after years of intensive exploration of 2D materials in science and technology, facile and scalable methods capable of producing stable 2D network polymers with uniformly decorated heteroatoms with/without holes remain limited. To overcome these issues, new layered 2D network polymers have been designed and synthesized. They have uniformly distributed heteroatoms , holes with heteroatoms  and transition metal nanoparticles on the holes . The structures were confirmed by scanning tunneling microscopy (STM) (Figure 1A and 1B). Based on the stoichiometry of the basal plane, they were, respectively, designated C3N, C2N 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. The results suggest that these newly-developed 2D network polymers offer greater opportunities, from wet-chemistry to device applications.