Electronic nature of vanadium nitride–carbon cluster composite materials obtained by the calcination of oxovanadylphthalocyanine

Calcination of oxovanadylphthalocyanine at 500–1000 °C under an argon atmosphere was performed. Elemental analyses, XRD and TEM measurements revealed that the calcined materials are composed of nano-sized vanadium nitride and carbon clusters. ESR spectral examinations suggested that the calcined materials have a photo-responsive charge separation feature. The decomposition of methylene blue and trimethylhydroquinone in the presence of the material calcined at 900 °C was accelerated by visible light irradiation. H2 evolution was detected from a mixture of the calcined material and water under the visible light irradiation.