Metal-Assisted and Solvent-Mediated Synthesis of Two-Dimensional Triazine Structures on Gram Scale
Faghani, Abbas et al. – 2021
Full author list: Faghani, Abbas and Gholami, Mohammad Fardin and Trunk, Matthias and Müller, Johannes and Pachfule, Pradip and Vogl, Sarah and Donskyi, Ievgen and Li, Mingjun and Nickl, Philip and Shao, Jingjing and Huang, Michael R S and Unger, Wolfgang E S and Arenal, Raul and Koch, Christoph T and Paulus, Beate and Rabe, Jürgen P and Thomas, Arne and Haag, Rainer and Adeli, Mohsen Covalent triazine frameworks are an emerging material class that have shown promising performance for a range of applications. In this work, we report on a metal-assisted and solvent-mediated reaction between calcium carbide and cyanuric chloride, as cheap and commercially available precursors, to synthesize two-dimensional triazine structures (2DTSs). The reaction between the solvent, dimethylformamide, and cyanuric chloride was promoted by calcium carbide and resulted in dimethylamino-s-triazine intermediates, which in turn undergo nucleophilic substitutions. This reaction was directed into two dimensions by calcium ions derived from calcium carbide and induced the formation of 2DTSs. The role of calcium ions to direct the two-dimensionality of the final structure was simulated using DFT and further proven by synthesizing molecular intermediates. The water content of the reaction medium was found to be a crucial factor that affected the structure of the products dramatically. While 2DTSs were obtained under anhydrous conditions, a mixture of graphitic material/2DTSs or only graphitic material (GM) was obtained in aqueous solutions. Due to the straightforward and gram-scale synthesis of 2DTSs, as well as their photothermal and photodynamic properties, they are promising materials for a wide range of future applications, including bacteria and virus incapacitation.