The Functional Chameleon of Materials Chemistry—Combining Carbon Structures into All‐Carbon Hybrid Nanomaterials with Intrinsic Porosity to Overcome the “Functionality‐Conductivity‐Dilemma” in Electrochemical Energy Storage and Electrocatalysis

Abstract

Nanoporous carbon materials can cover a remarkably wide range of physicochemical properties. They are widely applied in electrochemical energy storage and electrocatalysis. As a matter of fact, all these applications combine a chemical process at the electrode–electrolyte interface with the transport (and possibly the transfer) of electrons. This leads to multiple requirements which can hardly be fulfilled by one and the same material. This “functionality‐conductivity‐dilemma” can be minimized when multiple carbon‐based compounds are combined into porous all‐carbon hybrid nanomaterials. This article is giving a broad and general perspective on this approach from the viewpoint of materials chemists. The problem and existing solutions are first summarized. This is followed by an overview of the most important design principles for such porous materials, a chapter discussing recent examples from different fields where the formation of comparable structures has already been successfully applied, and an outlook over the future development of this field that is foreseen.

Real-Space Identification of Non-Noble Single Atomic Catalytic Sites within Metal-Coordinated Supramolecular Networks

“…One solution is to embed active single metal centers in 2D supramolecular structures, which allows control of their coordination and spatial assembly, e.g. via metal–nitrogen interactions. − Such an approach has been explored as a means to stabilize single copper atoms forming highly active and selective sites to be employed as non-noble metal SACs in electrochemical reactions. − Furthermore, nitrogen-rich organic materials have found importance as starting materials for scientific and industrial electrochemical applications. − Among various 2D supramolecular compounds, nanostructured triazine derivatives have been extensively studied and discussed as promising low-cost, non-noble metal catalysts for sustainable energy conversion and storage systems. ,− Melamine (2,4,6-triamino-s-triazine, Figure a) is a commonly used building block for nitrogen-containing heterocycles. The deamination of melamine during thermal polymerization creates an intermediate product called melem (2,5,8-triamino-tri-s-triazine, 2,5,8-triamino-heptazine, Figure a), − which also has been reported to form supramolecular assemblies capable of achieving a high electrocatalytic activity for the oxygen evolution reaction and oxidation reduction reaction (ORR) . , …”

Tunable Nitrogen-Doping of Sulfur Host Nanostructures for Stable and Shuttle-Free Room-Temperature Sodium–Sulfur Batteries

“…Nevertheless, one viable strategy to maximize both properties is the design of multicomponent hybrid nanostructures comprising both polar and conductive components, with carbonized core−shell structures recently proposed as a promising option. 54 Such hybridization and optimization of the electrode composition will be reported in future studies. Our results demonstrate the importance of polar groups in sulfur−host nanostructures and may further extend to other battery systems which face similar polarity−conductivity dilemmas.…”

“…In fact, lower conductivity can be compensated for using conductive additives. Nevertheless, one viable strategy to maximize both properties is the design of multicomponent hybrid nanostructures comprising both polar and conductive components, with carbonized core–shell structures recently proposed as a promising option . Such hybridization and optimization of the electrode composition will be reported in future studies.…”

Schiff‐bases for sustainable battery and supercapacitor electrodes

“…[ 79 ] More than 80% capacitance retention was achieved after 5000 cycles at 0.1 A g –1 . The performance of TpCOF was further enhanced by the formation of hybrid materials with conductive additives, [ 81 ] allowing for a higher amount of redox‐active centers to be reached by electrons. The hybrid materials were formed by the growth of poly(3,4‐ethylenedioxythiophene) (PEDOT), a conductive polymer in the pores of the COF, [ 82 ] or by the growth of the COF on the surface of conductive carbon materials such as nanotubes, [ 83 ] or graphene aerogels.…”