One‐Dimensional Covalent Organic Frameworks for the 2e⁻ Oxygen Reduction Reaction

Abstract

Two-dimensional covalent organic frameworks (2D COFs) are often employed for electrocatalytic systems because of their structural diversity. However, the efficiency of atom utilization is still in need of improvement, because the catalytic centers are located in the basal layers and it is difficult for the electrolytes to access them. Herein, we demonstrate the use of 1D COFs for the 2e À oxygen reduction reaction (ORR). The use of different four-connectivity blocks resulted in the prepared 1D COFs displaying good crystallinity, high surface areas, and excellent chemical stability. The more exposed catalytic sites resulted in the 1D COFs showing large electrochemically active surface areas, 4.8-fold of that of a control 2D COF, and thus enabled catalysis of the ORR with a higher H 2 O 2 selectivity of 85.8 % and activity, with a TOF value of 0.051 s À 1 at 0.2 V, than a 2D COF (72.9 % and 0.032 s À 1 ). This work paves the way for the development of COFs with low dimensions for electrocatalysis.

Molecular Design of Porous Organic Polymer-Derived Carbonaceous Electrocatalysts for Pinpointing Active Sites in Oxygen Reduction Reaction

“…(2) Inducing the reaction based on non-linear edges and suitable high-symmetry vertices [ 89 ]. Encouraged by this structural concept, Hu’s group recently synthesized two 1D COPs, based on 4,4′-(2,2-diphenylethene-1,1-diyl) dibenzaldehyde (TPEDH) linkers [ 90 ]. Restricted by the molecular symmetry, the dibenzaldehyde in the TPEDH guaranteed that the TPEDH-based COP only extend along the 1D direction.…”

Modulating the Oxygen Reduction Reaction Performance via Precisely Tuned Reactive Sites in Porphyrin-Based Covalent Organic Frameworks

“…However, the high-temperature treatment process often leads to energy consumption and uncontrollable structural changes, resulting in poorly defined active sites that restrict a more detailed understanding of the ORR mechanism. As such, several pyrolysis-free COFs with precise skeleton structures and exact active sites have been explored as catalysts for ORR [ 33 , 34 , 35 , 36 , 37 ]. Despite these advances, the research on porphyrin-based COFs with various transition metals (Co, Ni, Fe) as electrocatalysts for ORR is still in its early stages due to the difficulty in synthesizing metal porphyrin monomers.…”

A cobalt metalized polymer modulates the electronic structure of Pt nanoparticles to accelerate water dissociation kinetics

“…16,17 One-dimensional (1D) polymer structures in coordination chemistry have gained interest for their ability to elucidate the role of non-platinum atomic co-catalysts. 18 When stacked orderly, they provide more exposed edge sites, enhancing substance transport and enabling the study of synergistic mechanisms. 19–23…”