High-performance foam concrete containing multi-wall carbon nanotubes and ssDNA

Combining carbon nanotubes and biological macromolecules is expected to improve the properties of foaming agents and prefabricated foams, furthering the performance of foam concrete. The present study utilized hydroxylated multiwalled carbon nanotubes (MWCNTs-OH), single-stranded deoxyribonucleic acid (ssDNA), and sodium dodecyl benzene sulfonate (SDBS) for the preparation of novel stabilized foam and foam concrete. The designed foam was subsequently employed to fabricate foam concrete, and a detailed analysis of its micro/ macroscopic properties was conducted. The findings suggest that the ssDNA/MWCNTs-OH can be uniformly dispersed within the drainage channels amidst the bubbles, thereby significantly enhancing foam stability. Furthermore, the fluidity (up to 251 mm) and compressive strength (increased by up to 174 % compared to the control group) of the Foam concrete containing ssDNA/MWCNTs-OH exhibit a substantial improvement. The Xray computed tomography (X-CT) test results demonstrate a significant increase in the proportion of minuscule pores within the MWCNTs-OH-modified foam concrete, accompanied by a more regular pore shape. Scanning electron microscope (SEM) images reveal that MWCNTs-OH acts as nucleation sites on the pore walls, thereby substantiating the potential of ssDNA/MWCNTs-OH as a foam stabilizer and presenting an innovative pathway for the preparation of high-performance foam concrete.