Methods for producing macroscopic quantities of oxidized graphene nanoribbons are disclosed herein. The methods include providing a plurality of carbon nanotubes and reacting the plurality of carbon nanotubes with at least one oxidant to form oxidized graphene nanoribbons. The at least one oxidant is operable to longitudinally open the carbon nanotubes. In some embodiments, the reacting step takes place in the presence of at least one acid. In some embodiments, the reacting step takes place in the presence of at least one protective agent. Various embodiments of the present disclosure also include methods for producing reduced graphene nanoribbons by reacting oxidized graphene nanoribbons with at least one reducing agent. Oxidized graphene nanoribbons, reduced graphene nanoribbons and compositions and articles derived therefrom are also disclosed herein.