Bio-aerogels are a class of ultra-lightweight, extremely porous, solid materials derived from biological sources, such as natural polymers, proteins, or peptides, that have great potential in biomedical and environmental applications1, 2. Self-assembling peptides provide an optimal template for the fabrication of aerogels, due to their ease of synthesis, biocompatibility, biodegradability, structural tunability, and ability to be functionalized or mineralized3, 4. Building on from the previous reporting of the versatile self-assembly of the tachykinin neuropeptide Substance P into semi-flexible nanotubes that can catalyze bio-mineralization, we here focus on ultrashort tachykinin derivatives, hypothesized to drive native neuropeptide self-assembly5. Specifically, we report tachykinin-derived pentapeptides that self-assemble into nanofibrils in water and ethanol, resulting in nanostructured alcogels, enabling aerogel formation without the need for lengthy steps of solvent exchange before supercritical drying. The peptides also catalyze silica condensation in ethanol, enabling the fabrication of bio-composite aerogels by supercritical drying of a single-pot reaction mixture. Using a set of biophysical techniques, including fluorescence spectroscopy, infrared spectroscopy, rheology, electron microscopy, and synchrotron small/wide-angle X-ray scattering, complemented by molecular dynamics, we examine solvent influence on peptide nanostructure formation and its effects on the aerogel underlying nanostructure and crystallinity. Additionally, we investigate the composite systems incorporating silica, highlighting how peptide–silica interactions shape network architecture and mechanical behaviour.