Biomimetic and Biophilic Design of Multifunctional Symbiotic Lichen-Schwarz Metamaterial

Abstract

Noise and environmental problems are significant issues that affect human beings through the triggering of various stressors, including biological, chemical, physical, and psychological stressors. To address these issues, it is essential to develop environmentally friendly strategies, particularly in the field of materials manufacturing. This study presents a novel biomimetic and biophilic design of a lichen–Schwarz metamaterial (SLSM) that achieves multifunctional properties in noise attenuation and humidity control. The SLSM achieves acoustic and air humidifying multi-functions symbiotically through the use of triply periodic minimal surface (TPMS) and naturally occurring organic lichen. To attain partial or complete sound-blocking capabilities at specific frequencies, a Schwarz meta-symbiont in SLSM requires a parametric design of unit cell characteristics prior to 3D printing. The SLSM structure mimics a biomimetic shell and meta-symbiotic exoskeleton that safeguards the inner symbiont lichen by transitioning it from a dry and brittle state to a hydrated and flexible state during humidity control. The symbiotic lichen in SLSM offers superior sound attenuation across a broader frequency range and adds a unique function of humidity control, which is essential for sustainable architecture and multifunctional furniture in the forthcoming era of buildings.