Sustainable Nanofibril Interfaces for Strain‐Resilient and Multimodal Porous Bioelectronics

Porous soft bioelectronics have attracted significant attention due to their high breathability, long‐term biocompatibility, and other unique features inaccessible in nonporous counterparts. However, fabricating high‐quality multimodal bioelectronic components that operate stably under strain on porous substrates, along with integrating microfluidics for sweat management, remains challenging. In this study, cellulose nanofibrils (CNF) are explored, biomass‐derived sustainable biomaterials, as nanofibril interfaces with unprecedented interfacial robustness to enable high‐quality printing of strain‐resilient bioelectronics on porous substrates by reducing surface roughness and creating mechanical heterogeneity. Also, CNF‐based microfluidics can provide continuous sweat collection and refreshment, crucial for accurate biochemical sensing. Building upon these advancements, a multimodal porous wearable bioelectronic system is further developed capable of simultaneously detecting electrocardiograms and glucose and beta‐hydroxybutyrate in sweat for monitoring energy metabolism and consumption. This work introduces novel strategies for fabricating high‐quality, strain‐resilient porous bioelectronics with customizable multimodalities to meet arising personalized healthcare needs.