Nano-frictional mechano-reinforcing porous nanowires scaffolds

Artificial biomaterials with dynamic mechano-responsive behaviors similar to those of biological tissues have been drawing great attention.In this study,we report a TiO_(2)-based nanowire(TiO_(2)NWs)scaffolds,which exhibit dynamic mechano-responsive behaviors varying with the number and amplitude of nano-deformation cycles.It is found that the elastic and adhesive forces in the TiO_(2)NWs scaffolds can increase significantly after multiple cycles of nano-deformation.Further nanofriction experiments show the triboelectric effect of increasing elastic and adhesive forces during the nano-deformation cycles of TiO_(2)NWs scaffolds.These properties allow the TiO_(2)NW scaffolds to be designed and applied as intelligent artificial biomaterials to simulate biological tissues in the future.

Smart Fibers for Self‑Powered Electronic Skins

Smart fibers are considered as promising materials for the fabrication of wearable electronic skins owing to their features such as superior flexibility,light weight,high specific area,and ease of modification.Besides,piezoelectric or triboelectric electronic skins can respond to mechanical stimulation and directly convert the mechanical energy into electrical power for self-use,thereby providing an attractive method for tactile sensing and motion perception.The incorporation of sensing capabilities into smart fibers could be a powerful approach to the development of self-powered electronic skins.Herein,we review several aspects of the recent advancements in the development of self-powered electronic skins constructed with smart fibers.The summarized aspects include functional material selection,structural design,pressure sensing mechanism,and proof-to-concept demonstration to practical application.In particular,various fabrication strategies and a wide range of practical applications have been systematically introduced.Finally,a critical assessment of the challenges and promising perspectives for the development of fiber-based electronic skins has been presented.

Field-assisted thermionic emission toward quantitative modeling of charge-transfer mechanisms in contact electrification

Charge transfer mechanisms of contact electrification(CE)are essential for widening applications of the triboelectric nanogenerator,and thus are widely studied by scientists around the world.However,the quantitative modeling of CE,especially that between polymers,is still lacking.Herein,a model was proposed to describe the contributions from different mechanisms,including electron transfer and mass transfer in polymer/polymer CE through the fieldassisted thermionic emission,where three groups of charge transfer mechanisms were distinguished by the polarity of the charge transfer and the corresponding electric field.The results indicated that the total generated charge in CE is actually much larger than the measured net surface charge,confirming the bidirectional material-dependent charge transfer mechanisms between two surfaces,which is meaningful for understanding the millennium puzzle in triboelectrification and provides a new perspective for promoting the applications to tailor surface charge generation.