Metal-Free Molecular Catalysts for the Oxygen Reduction Reaction: Electron Affinity as an Activity Descriptor

Abstract

Heteroatom-doped polyaromatic hydrocarbons (or nanographenes) are promising molecular electrocatalysts for the oxygen reduction reaction (ORR). Here, we use density functional theory to investigate the first step of the ORR pathway (chemisorption) for a set of molecules with experimentally determined catalytic activities. Weak chemisorption is found for only negatively charged catalysts, and a strong correlation is observed between the computed electron affinities and experimental catalytic activities for a range of B-and B,Ndoped polyaromatic hydrocarbons. The electron affinity is put forward as a simple activity descriptor of charged (activated) catalysts on an electrode.

A cobalt harnessed phenanthroline and triphenylamine-based conjugated mesoporous polymer designed by a donor–acceptor approach for trifunctional electrocatalysis

“…Hence, it is anticipated to make a larger contribution to the electrochemical activity among the cobalt-stabilized models. 47–49…”

“…Hence, it is anticipated to make a larger contribution to the electrochemical activity among the cobalt-stabilized models. [47][48][49] Beginning with the ORR, the electrochemical activity of facilely prepared polymers was measured in 0.1 M KOH (pH = 13) using a typical three-electrode cell where an active catalyst lm was deposited on a glassy carbon (GC) electrode. CV (Fig.…”

Exploration of cobalt(ii) modification in a phenanthroline-based conjugated organic polymer towards trifunctional electrocatalysis

“…Similarly, the VIP of 8.29 eV of Co@TBB-phen was also higher than the VIP of TBB-phen. [57][58][59] Co@TBB-phen was also characterized via several physicochemical methods. Beginning with FTIR spectroscopy, the increase in transmittance peak observed at 1418 cm −1 was attributable to bonds arising from Co-phen N, along with stretching peaks at 1602 and 2212 cm −1 arising from aromatic -C-C-/-C-Nbonds, aromatic -C]C-/-C]N-, and -C^Cbonds, respectively.…”

Progress of Nonmetallic Electrocatalysts for Oxygen Reduction Reactions

“…Fuel cells and metal-air batteries are clean, efficient and safe batteries that convert chemical energy directly into electric energy, and they have the advantages of a high energy density, safety and environmental protection compared with traditional energy sources [ 1 , 2 ]. Currently, Pt-based cathode catalysts are widely used as the main catalyst of precious metals; however, high costs and limited reserves become major obstacles to the commercialization of fuel cells [ 3 , 4 , 5 ]. In addition, the fuel usually contains an amount of CO gas, easily making a Pt-based catalyst susceptible to poisoning [ 6 , 7 , 8 ].…”