Transfer of Vertical Graphene Nanosheets onto Flexible Substrates towards Supercapacitor Application

Abstract: Vertical graphene nanosheets (VGNs) are the material of choice for next-generation electronic device applications. The growing demand for flexible devices in electronic industry brings in restriction on growth temperature of the material of interest. However, VGNs with better structural quality is usually achieved at high growth temperatures. The difficulty associated with the direct growth on flexible substrates can overcome by adopting an effective strategy of transferring the well grown VGNs onto arbitrary flexible substrates through soft chemistry route. Hence, we demonstrated a simple, inexpensive and scalable technique for the transfer of VGNs onto arbitrary substrates without disrupting its morphology and structural properties. After transfer, the morphology, chemical structure and electronic properties are analyzed by scanning electron microscopy, Raman spectroscopy and four probe resistive methods, respectively. Associated characterization investigation indicates the retention of morphological, structural and electrical properties of transferred VGNs compared to as-grown one. Furthermore the storage capacity of the VGNs transferred onto flexible substrates is also examined. A very lower sheet resistance of 0.67 kOhm/sq. and excellent supercapacitance of 158 micro-Farrad/cm2 with 91.4% retention after 2000 cycles confirms the great prospective of this damage-free transfer approach of VGNs for flexible nanoelectronic device applications