Chitosan-Derived Nitrogen-Doped Carbon as a Support of Cobalt(II)-Phthalocyanine/Gold Nanoparticles for Photocatalytic Water Splitting

Abstract

Water splitting is considered one of the worthy approaches to generate hydrogen as a green fuel with diverse applications. Promoting this reaction with the photocatalytic strategy enjoys a free source of solar energy, without the use of expensive instruments. In this research, gold nanoparticles and cobalt(II)-phthalocyanine were deposited on nitrogen-doped carbon, obtained from chitosan, to afford a photocatalytic water splitting at the rate of 792 mol mol_Au^-1 h^-1. Gold as the catalyst in contact with cobalt(II)-phthalocyanine as the sensitizer and nitrogen-doped carbon as the support/semiconductor provided a desired heterojunction for the photocatalytic purpose. The nanocomposite showed remarkable light harvesting in the region of visible light with a band gap of 2.01 eV. While a facile protocol to the synthesis of the mentioned photocatalyst by a simple thermal treatment of cobalt(II)-phthalocyanine and chitosan could be invaluable, this research pointed out the significance of cobalt(II)-phthalocyanine as the sensitizer in the gold photocatalytic transformations.