Research Progress in Tailoring the Microstructure of Resorcinol-Formaldehyde Organic/Carbon Aerogel

Because of the excellent ablation resistance and physical/chemical properties, phenolic/carbon aerogel has great potential in the fields of acoustic/thermal resistance material, absorption material, energy storage material, sensor, aerospace industry, etc. This mini-review introduced the main factors in the synthesis of resorcinol-formaldehyde organic/carbon aerogel, including catalyst, additives and drying methods. First, the catalytic mechanism of acids/bases, the impact of the catalyst types and solution pH value on the microstructure of the aerogel were discussed. Then, while the interaction mechanism of surfactants was analyzed, how the types and the amount of surfactants influence the microstructure was elucidated. Further, the role of additives, such as carbon nanotubes, graphene oxide, chitosan, salts, etc., was discussed. The effects of different drying methods i.e., supercritical drying, freeze-drying and ambient pressure drying, on the microstructure of the aerogel were compared, with an emphasis on the prerequisites and principles for ambient pressure drying. Finally, the current challenges were summarized and the possible future developments of resorcinol-formaldehyde polymer/carbon aerogel were prospected, such as improvement of mechanical properties, cost-effective, super elastic aerogel and 3D printable aerogel. © 2022, Materials Review Magazine. All right reserved.