Sunlight induced photodegradation of toxic azo dye by self-doped iron oxide nano-carbon from waste printer ink

Abstract A simpler and sustainable approach for the isolation of self-doped iron-oxide nano-carbons from the waste black toner ink as a “freely available waste carbon black precursor is presented here.” The residual waste printer ink is usually known as the black toner ink and generally discarded as waste. In the simpler process, the waste black toner ink has been carbonized in a muffle furnace at ~600 °C and on further oxidation converted to its self-doped functionalized version as functionalized iron-oxide nano-carbons (f-FeO-NC). The f-FeO-NC has been used for the photocatalytic degradation of a toxic azo dye as Congo Red (CR) under the irradiation of natural sunlight. Based on its ease in accessibility and process ability, the transformation of the residual discarded waste ink to iron-oxide doped nano-carbons provides a better photocatalyst (sunlight-induced photodegradation) and hence provide a sustainable approach towards the successful waste management of the waste black toner ink.