Simple Aqueous Solution Route to Luminescent Carbogenic Dots from Carbohydrates

A simple aqueous solution route to prepare luminescent carbogenic dots by using carbohydrates as starting materials, was reported. The carbohydrates were dehydrated using concentrated sulfuric acid, producing carbonaceous materials. The obtained carbonaceous materials were then broken down into individual carbogenic nanoparticles by treatment with nitric acid. Finally, the carbogenic nanoparticles were passivated using amine-terminated compounds, producing luminescent carbogenic dots. FT-IR and Raman spectroscopy were used to characterize the carbonaceous materials obtained from the treatment of glucose, sucrose and starch carbohydrates with concentrated sulfuric acid. Neither the carbonaceous materials nor their aqueous suspension exhibited any detectable photoluminescence. After refluxing the carbonaceous materials in a nitric acid solution for 12 h, the resulting solution exhibited a weak photoluminescence.