Adsorption and reaction of formic acid on Cu(111): The importance of the intermolecular interaction

Formic acid (HCOOH) is known to be catalytically decomposed on low index Cu surfaces into hydrogen and carbon dioxide via the formate (HCOO) intermediate. HCOOH is known to form polymeric (overlayer) structures on a Cu(111) surface. However, the structure of the polymeric HCOOH has been debated and is not yet fully understood. In this work, we use van der Waals inclusive density functional theory calculations in combination with scanning tunneling microscopy / atomic force microscopy and clarify the structural and vibrational properties of the polymeric HCOOH on a Cu(111) surface [1,2]. We also investigate the catalytic dehydrogenation of HCOOH in the overlayer structure and clarify the active site and the role of the edge and hydrogen-bonding formed between HCOOH molecules [1]. Furthermore, we clarify the formation of various chain-like HCOOH-HCOO and HCOO nanostructures, depending on the annealing temperature [2]. Our study reveals the importance of intermolecular interaction and serves as a fundamental step toward full understanding of the catalytic reaction of HCOOH and development of more efficient catalysts.

[1] S. E. M. Putra, et al., Phys. Rev. Materials 5, 075801 (2021).

[2] A. Shiotari, S. E. M. Putra, et al., Small 17, 2008010 (2021).