Strain-induced pseudo-magnetic fields and charging effects on CVD-grown graphene

► Atomically resolved imaging and spectroscopy of CVD-grown graphene are studied by means of scanning tunneling microscopy ► Strain-induced giant pseudo-magnetic fields in CVD-grown graphene appear as density-of-states peaks at quantized energies ► The quantized energies correspond to pseudo-magnetic field-induced integer and fractional Landau levels in grapheme ► Nano-scale charging effects in graphene are revealed by the enhanced local density of states in highly strained regions ► Both the giant pseudo-magnetic fields and charging effects in CVD-grown graphene diminish upon the reduction of strain