Table 2.

Summary of several approaches for defects modulation in graphene crystals.

Approaches	Key Content	Substrate	Induced Disorders	Refs.
Particle Irradiation	Ar+ ions	Bilayer graphene	Interstitials and vacancies	[326]
	Ar+ ions	SiO2-supported monolayer graphene	Vacancies and substitutional Impurities	[336]
	$\alpha$-beams (He2+)	Monolayer graphene	Vacancies, C = O and C–OO bonds	[327]
	Electrons	Monolayer CVD graphene	Vacancies, complex closed-loop defects, and dislocation pairs	[328]
	Electrons	Mechanically exfoliated monolayer graphene	Polygons and low-energy multivacancy	[339]
Thermal Annealing	~ 200 °C	CVD graphene	sp3 defects and partially formed radical sites	[329]
	500–1000 °C	rGO	Free radicals and oxygen groups	[330]
Chemical Reaction	CO and NO molecules	Monolayer graphene after irradiation	SV and N-doping	[331]
	Fluorinated maleimide molecules and a toluene solution	Monolayer and bilayer epitaxial graphene	sp3-defects and standing-wave patterns	[332]
	NH3 plasma	Polycrystalline graphene	Pyridine-like N, pyrrolelike N, and nitrites (NOx)	[347]
Strain Treatment	Uniaxial strain	Polycrystalline graphene	Lattice distortion, Grain boundaries	[333]
	Shear strain	CVD graphene	Wrinkles, transverse conducting channels and grain boundaries	[334]