A joint research team (consisting of our department members Prof. Jung-Woo Choi, Prof. Byung-Jin Cho, and Ph.D. candidate Choong-Sun Kim, members of the Department of Materials Science and Engineering Prof. Sang-Wook Kim and Ph.D. candidate Kyung-Eun Lee, and Ph.D. Jung-Min Lee of the Department of Mechanical Engineering) has successively developed an ultra-slim thermoacoustic speaker on September 9th, 2016 that acquires electrical energy from 3D graphene aerogels to generate sounds without vibrating a thin membrane-like film.
This thermoacoustic speaker relies on the fundamental basis of air vibrations transferred from graphene generated thermo-waves. Compared to the conventional voice-coil speakers, this speaker generate sounds without film vibrations, having an advantage of making the speaker ultra-slim.
The joint team used 3D graphene aerogels acquired from n-doping and reducing aerogels after freeze-drying oxidized graphene solutions, rather than using carbon nanotube (CNT) or 2D graphene that show high resistance and low mechanical stability.
From this process, a production-friendly, adhesive, and highly efficient thermoacoustic speaker was developed.
This research was presented in IEEE Spectrum news, ACS weekly news, and ACS Advanced Materials & Interfaces (AMI) journal.
The joint study was supported by Samsung Science & Technology Foundation and National Research Foundation of Korea.
[ACS weekly news]
Bringing graphene speakers to the mobile market
[IEEE Spectrum Magazine]
Graphene Enables Flat Speakers for Mobile Audio Systems
[N-doped 3D large rGO graphene loudspeaker]
1. Fabrication Process