jp9b05994_si_001.pdf (628.42 kB)
Revisiting Formic Acid Decomposition by a Graph-Theoretical Approach
journal contribution
posted on 2019-10-17, 20:43 authored by Tomonori Ida, Manami Nishida, Yuta HoriFormic
acid (HCOOH) is a suitable hydrogen storage material because
of its high gravimetric and volumetric H2 capacities. Although
H2 is produced by the thermal decomposition of HCOOH (HCOOH
→ H2 + CO2, dehydrogenation), the production
of water and carbon monoxide (HCOOH → H2O + CO,
dehydration) is the major pathway in HCOOH decomposition despite the
thermodynamic favorability of the dehydrogenation process over the
dehydration process. A large number of experimental and theoretical
studies have suggested that both processes are competitive or that
the dehydrogenation process has a lower activation energy in HCOOH
decomposition. In the present work, we revisit the factors hindering
the progress of the dehydrogenation process, using a whole chemical
reaction network based on the graph theory. The calculated chemical
reaction network shows that the factor controlling the dehydrogenation
and dehydration processes is simple and fundamental and can be explained
by the oxidation number of carbon and the betweenness centrality.
Based on this understanding of the factors hindering the progress
of dehydrogenation, the advantage of the dehydration process in HCOOH
decomposition is discussed.