IMPACT OF MECHANICAL DEFORMATION ON THE ELECTRICAL PROPERTIES OF CARBON NANOWALLS

Carbon nanowalls (CNWs) are promising carbon nanomaterials for flexible and wearable electronic applications due to their unique vertically oriented architecture and high electrical conductivity. In this work, the influence of mechanical deformation on the electrical properties of flexible CNW films was systematically investigated. CNWs were synthesized by inductively coupled plasma–enhanced chemical vapor deposition and transferred onto polymer substrates for electromechanical testing. Hall effect measurements revealed that increasing bending strain and cyclic mechanical loading result in a gradual increase in sheet resistance accompanied by a decrease in electrical conductivity and charge carrier mobility, while the carrier concentration remains nearly unchanged. Scanning electron microscopy showed the formation of deformation-induced microcracks and partial disruption of conductive pathways after repeated bending, whereas the overall nanowall morphology was largely preserved. Raman spectroscopy confirmed the stability of the sp2 carbon framework, with an increased defect-related signal after deformation. The strong correlation between electrical, morphological, and spectroscopic results demonstrates that defect accumulation governs the electromechanical response of CNWs. These findings highlight the mechanical robustness of CNWs and their suitability for flexible electronic and sensing devices.

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