Sonication basically exfoliates GO to graphene layers.. and there are many alternatives like electro-chemical exfoliation, exfoliation by ball milling, exfoliation in super-critical fluids or exfoliating with polymeric foaming agents..but in all these alternate techniques, the yield will be low.. except in electro-chemical if the medium is ionic liquid, the yield and quality of graphene is good.
Sonication basically exfoliates GO to graphene layers.. and there are many alternatives like electro-chemical exfoliation, exfoliation by ball milling, exfoliation in super-critical fluids or exfoliating with polymeric foaming agents..but in all these alternate techniques, the yield will be low.. except in electro-chemical if the medium is ionic liquid, the yield and quality of graphene is good.