▎ 摘　　要

Splitting of D band is observed in vertically aligned graphene nanowalls (VAGNWs) during analysis of Raman spectroscopy for the first time and two distinct peaks were observed, designated as D-1 and D-2. Evolution of D band with increasing laser power is studied and it is seen that intensity and full width at half maxima (FWHM) of D-2 get reduced with increasing laser power. I-D/I-G values of deposited VAGNWs showed a decreasing trend with increasing laser power indicating that defects have slightly reduced with increasing laser power. It is also observed that D-/ peak at high laser power almost merged with G peak like highly defective graphene sheets. Defect analysis showed that all the samples have high degree of stage 2 defect. Interestingly, no splitting was observed in G(/) band by increasing laser power and VAGNWs kept their turbostratic nature intact through this peak.