Coordination Shell Dependent Activity of CuCo Diatomic Catalysts for Oxygen Reduction, Oxygen Evolution, and Hydrogen Evolution Reaction

Abstract

Challenges in rational designing dual‐atom catalysts (DACs) give a strong motivation to construct coordination‐activity correlations. Here, thorough coordination‐activity correlations of DACs based on how the changes in coordination shells (CSs) of dual‐atom Cu,Co centers influence their electrocatalytic activity in oxygen reduction reaction(ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) is constructed. First, Cu,Co DACs with different CSs modifications are fabricated by using a controlled “precursors‐preselection” approach. Three DACs with unique coordination environments are characterized as secondary S atoms that directly bond to Cu,Co‐N6 in lower CSs, indirectly bond in neighboring CSs, and are doped in higher CSs, respectively. Then, experimentally and theoretically, a coordination correlation resembling a planet‐satellite system, where satellite coordinated atoms (heteroatom N, S) surround Cu‐Co dual‐atom entity in various orbitals CSs. By evaluating electrocatalytic activity indicators, differences are identified in electronic structure and electrocatalytic performance of Cu and Co centers in ORR, OER, and HER. Interestingly, initial CSs modifications for DACs may not always be advantageous for electrocatalysis. This work offers valuable insight for designing DACs for diverse applications.

Graphitic Carbocatalysts with Pentagon Defects Synthesized from Polyperylene for Electrocatalytic Oxygen Reduction and Flexible Zinc-Air Batteries

“…Given this extremely low level of Fe, it is evident that such a trace amount is insufficient to contribute to the catalytic properties of the fabricated carbocatalysts. Of note, methanol tolerance is also an important performance parameter in the electrocatalytic ORR process, which is crucial for the use of electrodes in fuel cells . GDHfCN electrode exhibits almost no change in current density upon the addition of 0.5 M methanol solution (Figure S11), whereas the commercial Pt/C electrode exhibits a significant decay in current density, implying the potential advantage of GDHfCN as an ORR cathode catalyst in practical fuel cells.…”

Role of Heteroatom Doping in Enhancing the Catalytic Activities and Stability of Atomically Dispersed Metal Catalysts for Oxygen Evolution Reaction

“…Hu et al found that FeCoN 7 and FeCoN 8 possess better catalytic activity and stability compared with FeCoN 6 both for ORR and OER . Chen et al found that the initial modifications in the first nearest neighbor coordination for CuCo DACs may not always be advantageous for electrocatalysis in OER . Even though DACs have made great achievements as electrocatalysts in the OER, the role of the local coordination environment of the active sites in enhancing the OER activity has not yet been fully understood, especially the regulation of the OER catalytic performance by the second nearest neighbor coordination of the active sites in atomically dispersed metal catalysts.…”