Hierarchically Structured M13 Phage Aerogel for Enhanced Sound-Absorption

Aerogels are a novel type of open-cell porous material. They are particularly suitable for passive sound-absorption due to their high porosity and high-surface areas of the internal structures, but with the drawbacks of limited absorption rate of low-frequency sound and poor mechanical performance. Here, it is first demonstrated that the M13 phage aerogel(M13AG) with hierarchically porous and ribbing structures is beneficial to sound-absorption and the local piezoelectric effect attributed to M13 phages can further improve the sound-absorption ability in the low-frequency. The sound-absorption coefficient of the M13AG with thickness of 20 mm attains peak value of 0.992 at 1600 Hz. In addition, the M13AG is assembled on a metallic foam framework to enhance its mechanical performance. The resulting M13AG/nickel foam exhibits enhanced compressive yield strength up to 0.14 MPa. This study opens up a new opportunity for passive sound-absorption.