Hybrid Carbon Nitride/Cobalt Phthalocyanine Nanocomposites for Efficient Photocatalytic Hydrogen Generation
Lakshman Sundar Arumugam, Javier E. Durantini, Jorge Follana‐Berná, Frederik Schiller, Ane Etxebarria, Lorenzo Forzanini, Sara Barja, Ángela Sastre‐Santos, Sixto Giménez
Abstract
The photocatalytic production of hydrogen stands out as a promising strategy to convert and store solar energy as chemical energy in the form of a sustainable energy carrier. In the present study, a hybrid photocatalyst based on cobalt phthalocyanine (CoPc) coupled with polymeric carbon nitride (CN) is synthesized using a simple, cost-effective, and upscalable method. Both components are held together in the hybrid nanocomposite via π–π interactions, as shown by detailed structural and optical characterization. The synergistic interaction between both components, CN, a metal-free semiconductor, valued for its stability and tunable electronic properties, and CoPc, known for its excellent light absorption and electronic properties, is evidenced in a proof-of-concept photocatalytic reaction: the photo-oxidation of benzyl alcohol (BzOH) to benzaldehyde (BzO). Chemical trapping reagents were employed to elucidate the reaction mechanism, showing favorable recombination dynamics of the hybrid photocatalyst (CoPc/CN) compared to the individual components. Furthermore, photocatalytic hydrogen production was conducted in an aqueous solution using triethanolamine (TEOA) as an electron donor, with the optimized CoPc/CN nanocomposite producing 1136.5 μmol h –1 g cat –1 of H 2, achieving a 50% higher hydrogen yield compared to pristine CN. These results contribute to the design of high-performance photocatalytic materials for promising solar-to-X transformations.