A simple molecular design for tunable two-dimensional imine covalent organic frameworks for optoelectronic applications†
Abstract
Two-dimensional covalent organic frameworks (2D-COFs) belong to a new class of molecular materials that have attracted huge attention in recent years due to their analogous nature to graphene. In this work, we present a systematic study of the electronic structure, carrier mobility and work function of imine based 2D-COFs. We identify these 2D-COFs as a new class of semiconducting materials with tunable electronic/optoelectronic properties and significant mobility. The results show that by rationally doping 2D-COFs at the molecular level, it is possible to control their structural and optoelectronic responses. Cohesive energy calculations revealed that all the studied 2D-COFs are thermodynamically stable. Also, the calculated binding energy of 2D-COFs on HOPG was found to be less than 1 eV, which indicates that the COFs do not interact strongly with HOPG, and it will not affect their electronic properties. Additionally, we have synthesized a 2,4,6-pyrimidinetriamine based 2D-COF and experimentally measured its band gap using scanning tunnelling spectroscopy. The experimentally measured band gap is found to be in good agreement with theoretical results.
Please wait while we load your content...
