Tunability of the Electronic Properties of Covalent Organic Frameworks

Research on carbon-based covalent organic frameworks (COFs) is a fascinating area in the field of material science due to their excellent performance and broad range of applications in technology. COFs have extraordinary features like a well-defined highly symmetric periodic structure, large porosity and surface area, rigid frame, etc. However, despite their exceptional properties, it is difficult to regulate and tune their electronic properties, thus hindering the potential implementation in the electronic devices and nanotechnology purposes. Here, we have developed seven new types of COFs consisting of triboronate ester along with 2,4,6-triphenyl-1,3,5-triazine (TPT) linkers and carbon-containing C6H4 linkers with the intercalation of Fe atoms between two layers of the COFs. The equilibrium crystal structures, intrinsic properties, and the electronic properties of the newly developed COFs were studied by applying the first-principles-based DFT-D method. This study reveals that the d-subshell electrons of the intercalated iron atoms regulate and tune the electronic properties of the COF materials. These findings suggest that the electronic properties of the COFs can be finely altered by the intercalation of transition metal (here, Fe) atoms, which affects the state of the material from a conductor to semiconductor. This study opens a new approach to design organic porous materials with tunable properties for application toward nanoelectronics and other applications.