Shock induced conversion of carbon dioxide to few layer graphene

Using solid CO₂ (dry ice) as the carbon source, few layer graphene sheets were synthesized by reduction of CO₂ with calcium hydride under shock wave loading. In addition, by adding ammonium nitrate to the reaction system, nitrogen-doped graphene material was formed in this one-step shock treatment. The recovered samples were characterized using various techniques such as transmission electron microscopy, scanning electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy, and therein the nitrogen-doped graphene was demonstrated to act as a metal-free electrode with an efficient electrocatalytic activity toward oxygen reduction reaction in alkaline solution. This work provides an innovative route for producing one of the most promising carbon nanostructures by employing CO₂ as a raw material which is popularly known as the greenhouse gas.