Template‐Free Formation of Regular Macroporosity in Carbon Materials Made from a Folded Polymer Precursor

Abstract

Porous carbon materials attract great interest in a wide range of applications such as batteries, fuel cells, and membranes, due to their large surface area, structural and compositional tunability, and chemical stability. While micropores are typically obtained when preparing carbon materials by pyrolysis, the fabrication of mesoporous, and especially macroporous carbons is more challenging, yet important for enhancing mass transport. Herein, template‐free regular macroporous carbons are prepared from a mixture of unfolded (linear) and folded (single‐chain nanoparticles, SCNP) polyvinylpyrrolidone chains. While having the same chemical composition, the different molecular architectures lead to phase separation even before pyrolysis, creating a dense cell architecture, which is retained upon carbonization. Upon increasing the SCNP content, the homogeneity of the pore network increases and the specific surface area is enlarged 3‐5‐fold, until ideal properties are obtained at 75% SCNP, as observed by high‐resolution scanning electron microscopy and N2 physisorption porosimetry. The materials are further investigated as hydrazine oxidation electrocatalysts, demonstrating the link between the evolving morphology and current density. Importantly, this study demonstrates the role of polymer architecture in macroporosity templating in carbon materials, providing a new approach to develop complex carbon architectures without the need for external templating.

Porous organic polymers for drug delivery: hierarchical pore structures, variable morphologies, and biological properties

“…Review templated method, 84 the template-free method, 85 the mechanical methods, and post forming/control methods (such as electrospun methods and 3D printing methods) (Fig. 3).…”

“…The morphologies, pore sizes, and surface area of POPs have significant effects on their performances. Nowadays, the methods to control theses aspects of POPs mainly include the templated method, 84 the template-free method, 85 the mechanical methods, and post forming/control methods (such as electrospun methods and 3D printing methods) (Fig. 3).…”

Reversible Change in Performances of Polymer Networks via Invertible Architecture–Transformation of Cross-Links

“…23,24 With these considerations in mind and inspired by reversible SCNPs synthesis, we wondered if it would be possible to exploit functional and structure transformable SCNPs to drive gelation and yield networks that consist of SCNPs linked together by linear polymers (Scheme 1). Although few literature have reported SCNPs−cross-linked polymer networks, 25,26 no detailed research has been conducted on the changes in network performance caused by introducing SCNPs into networks. Meanwhile, the contribution of the size of the SCNP to the performance of polymer networks is currently unknown.…”

A bimetallic 3D interconnected metal–organic framework with 2D morphology and its derived electrocatalyst for oxygen reduction

“…[13][14][15] There are many strategies to prepare NC materials, such as hetero-atom doping, and the pyrolysis of polymers or metalorganic frameworks (MOFs). [16][17][18][19] Moreover, metal and N codoped carbon (M-NC) materials could be prepared by pyrolyzing MOFs, and show high activity for the ORR. [20][21][22][23][24][25][26] Therefore, designing novel MOFs as precursors to synthesize M-NC materials is important for the development of electrocatalysts with high activity.…”