2D Hemiporphyrazine: A new nanoporous material

Crystalline microporous materials are solids formed by interconnected pores of less than 2 nm in size. Typically, they possess large surface areas desirable for versatile applications such as catalysis, gas adsorption, and energy storage. In the present work, we propose a new porphyrin-based 2D nanoporous crystal, named 2D Hemiporphyrazine (2DH), which is formed by topologically assembling H5C13N4 porphyrins. We have considered its monolayer, bi-layer, and molecular crystal (bulk) arrangements. We carried out DFT calculations to investigate 2DH structural and electronic properties. Results show that 2DH is a very stable structure with a direct bandgap of 0.65 eV and significant optical absorption in the visible range. Simulations also showed the existence of proton transfer between nitrogen atoms. It is the first report on the site-specific hydrogen exchange process in 2D crystals.