Aerosol Gelation: Synthesis of a Novel, Lightweight, High Specific Surface Area Material

Abstract

We demonstrate that an aerosol can gel. This gelation is then used for a one-step method to produce an ultralow density porous carbon material. This material is named an aerosol gel because it is made via gelation of particles in the aerosol phase. The carbon aerosol gels have high specific surface area (200–350 m ² /g), an extremely low density (2.5–5.0 mg/cc) and a high electrical conductivity, properties similar to conventional aerogels. The primary particles of the carbon aerosol gels are highly crystalline with a narrow (002) graphitic X-ray diffraction peak. Key aspects to form a gel from an aerosol are large volume fraction, ca. 10 ⁻⁴ or greater, and small primary particle size, 50 nm or smaller, so that the gel time is fast compared to other characteristic times.

Acknowledgments

We thank Prof. Kenneth J. Klabunde for use of his BET instrument and also thank Dr. Daniel L. Boyle for TEM work. This research was supported by NASA Grant No. NNC04GA74G and NSF Grant No. CTS 0080017.