A Pyrolysis‐Free Covalent Organic Polymer for Oxygen Reduction

Abstract

Highly efficient electrocatalysts derived from metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) for oxygen reduction reaction (ORR) have been developed. However, the subsequent pyrolysis is often needed owing to their poor intrinsic electrical conductivity, leading to undesirable structure changes and destruction of the original fine structure. Now, hybrid electrocatalysts were formed by self-assembling pristine covalent organic polymer (COP) with reduced graphene oxide (rGO). The electrical conductivity of the hybridized COP/rGO materials is increased by more than seven orders of magnitude (from 3.06×10 to 2.56×10 S m ) compared with pure COPs. The ORR activities of the hybrid are enhanced significantly by the synergetic effect between highly active COP and highly conductive rGO. This COP/rGO hybrid catalyst exhibited a remarkable positive half-wave (150 mV).

A Phthalocyanine‐Based Layered Two‐Dimensional Conjugated Metal–Organic Framework as a Highly Efficient Electrocatalyst for the Oxygen Reduction Reaction

“…[2,[9][10][11][12] However,g reat challenges still remain for conventional MOFs including electrical insulators and the blockage of metal centers by organic ligands;this leads to inferior activity (halfwave potential E 1/2 < 0.8 Vv s. RHE) and dramatically limits their broader applications in electrocatalysis.P yrolysis of MOFs to provide metal-and heteroatom-doped porous carbons has been widely demonstrated to improve the catalytic activity. [15] In order to address these challenges,t he development of conductive two-dimensional (2D) conjugated MOFs,i .e., atomically ordered, planar metal-organic networks extending in two dimensions with fully in-plane p-delocalization and weak out-of-plane p-p stacking is of great significance in electrocatalysis.This is due to their unique 2D features as well as improved electron transfer capacity and the high utilization of exposed active sites,inaddition to the inherent advantages of traditional MOFs. [15] In order to address these challenges,t he development of conductive two-dimensional (2D) conjugated MOFs,i .e., atomically ordered, planar metal-organic networks extending in two dimensions with fully in-plane p-delocalization and weak out-of-plane p-p stacking is of great significance in electrocatalysis.This is due to their unique 2D features as well as improved electron transfer capacity and the high utilization of exposed active sites,inaddition to the inherent advantages of traditional MOFs.…”

“…[2,13,14] However,w ith this method the welldefined molecular active sites are sacrificed. [15] In order to address these challenges,t he development of conductive two-dimensional (2D) conjugated MOFs,i .e., atomically ordered, planar metal-organic networks extending in two dimensions with fully in-plane p-delocalization and weak out-of-plane p-p stacking is of great significance in electrocatalysis.This is due to their unique 2D features as well as improved electron transfer capacity and the high utilization of exposed active sites,inaddition to the inherent advantages of traditional MOFs. [13,14,[16][17][18][19][20][21][22][23][24] In particular,s uch MOFs can provide an ideal platform for the investigation of the mechanism of the ORR process,w hich is essential for the rational design of electrocatalysts.…”

COF‐Derived N,P Co‐Doped Carbon as a Metal‐Free Catalyst for Highly Efficient Oxygen Reduction Reaction

“…Their molecular designability makes it easy to incorporate active groups and units into the extended frameworks, leading to the good performance on energy conversion, like carbon dioxide reduction reaction . However, the intrinsically poor conductivities and relative lower content of heteroatoms in most of COFs result in limited electroactivities of oxygen reduction reaction (ORR) . Therefore, thermally pyrolyzing COFs into carbon nanomaterials is a rational way to overcome this drawback.…”

“…[7] However, the intrinsically poor conductivities and relative lower content of heteroatoms in most of COFs result in limited electroactivities of oxygen reduction reaction (ORR). [8,9] Therefore, thermally pyrolyzing COFs into carbon nanomaterials is a rational way to overcome this drawback.…”

Heterocyclization Strategy for Construction of Linear Conjugated Polymers: Efficient Metal‐Free Electrocatalysts for Oxygen Reduction

“…These values are among the highest values reported for the ORR with metal-free polymers as catalysts and without the process of pyrolysis and heteroatom doping. [10][11][12][13][14][15][16][17] DFT calculations reveal that the combined structure of N-and Sheterocycles is the key to developing novel electrocatalysts with distinct chemical compositions and molecular structures for efficient ORR catalytic activity.…”