Self-Assembled Supramolecular Hybrid of Carbon Nanodots and Polyoxometalates for Visible-Light-Driven Water Oxidation

Water splitting is considered the most attractive pursuit in the field of solar energy conversion. In this study, we report the synthesis and application of a supramolecular hybrid of carbon nanodot (CD) and cobalt polyoxometalate (Co-POM) to solar water oxidation. The self-assembly of the alginate-based CD and Co-POM led to the formation of a spherical hybrid of CD/Co-POM. Owing to the facile transfer of photogenerated holes from CD under visible light irradiation, the hybrid donor–acceptor type of CD/Co-POM enabled the rapid scavenging of holes and accumulation of a long-lived oxidation state of Co-POM for efficient solar water oxidation, outperforming conventional [Ru(bpy)3]2+-based systems. We believe that this study offers new insights into the development of CD-based nanocomposites with various photocatalytic and optoelectronic applications.