A method of production of carbon nanoparticles comprises the steps of: providing on substrate particles a transition metal compound which is decomposable to yield the transition metal under conditions permitting carbon nanoparticle formation, contacting a gaseous carbon source with the substrate particles, before, during or after said contacting step, decomposing the transition metal compound to yield the transition metal on the substrate particles, forming carbon nanoparticles by decomposition of the carbon source catalysed by the transition metal, and collecting the carbon nanoparticles formed.