Carbon aerogels with improved flexibility by sphere templating.

Miralem Salihovic,Johannes Bernardi,Michael S Elsaesser,Nicola Hüsing,Volker Presser

doi:10.1039/c8ra04848g

Abstract

Mechanically reversible compressible resorcinol–formaldehyde (RF) aerogels can be converted into mechanically reversible compressible carbon aerogels (CA) by carbonization in an inert atmosphere. By incorporation of polystyrene spheres into the RF gels as a sacrificial template, it is possible to create macropores with controlled size within the carbon framework during carbonization. The resulting templated carbon aerogel shows enhanced mechanical flexibility during compression compared to pristine samples. In addition, the presence of hierarchical porosity provides a porous architecture attractive for energy storage applications, such as supercapacitors.

Highlights

Carbon aerogels (CAs) are fascinating solids with a unique combination of material properties, such as electrical and thermal conductivity, low density, and high surface area.[1,2] carbon aerogels (CA) are attractive for many applications, including supercapacitors,[3] thermal insulation,[4] and ltration/separation.[5]
Subsequent carbonization of the RF/PS composite aerogels caused the thermal decomposition of the PS spheres, resulting in the formation of hollow spheres throughout the nal monolithic carbon aerogel network
As PS decomposes during carbonization, the PS spheres become hollow with a wall thickness of approximately 10 nm, they retain 95% of the initial diameter, and are embedded in the globular carbon network (ESI, Fig. S6†)

Summary

Introduction

Carbon aerogels (CAs) are fascinating solids with a unique combination of material properties, such as electrical and thermal conductivity, low density, and high surface area.[1,2] CAs are attractive for many applications, including supercapacitors,[3] thermal insulation,[4] and ltration/separation.[5]. We used polystyrene (PS) as a template for macropores in the ligree materials network to obtain mechanically reversible compressible carbon aerogels.

Results

Conclusion