DFT study on a fluorine-functionalized nitrogen- and boron-doped triangulene as an electrocatalyst for the oxygen reduction reaction

Abstract

Developing catalyst materials alternative to platinum (Pt) for proton exchange membrane fuel cells (PEMFCs) is a necessary ongoing research direction. In this work, we used metal-free catalysts namely, fluorine (F)-functionalized nitrogen (N) and boron (B)-doped triangulene (C₂₂H₁₂), as electrocatalysts to enhance the oxygen reduction reaction (ORR) as an alternative to expensive Pt catalysts. The minimum energy barrier of the most favorable pathway for the initial step (*O₂ adsorption) is 0.31 eV and the *OOH and *OH intermediate steps are 0.29 and 0.06 eV, respectively. The free energy (ΔG) values are highly exothermic and energetically favorable. The F-functionalized N-doped triangulene (F–N-tri) has the highest stability and excellent catalytic activity in comparison to F-functionalized B-doped triangulene (F–B-tri). The minimum overpotential of F–N-tri is 1.16 V which demonstrates superior catalytic activity and hence can be utilized for PEMFC applications.