Preparation of Co₉S₈ nanostructure with double comb copolymer derived mesoporous carbon for solar energy conversion catalyst

This work reports the development of a facile hybrid based on Co₉S₈ nanostructure embedded on sheets of mesoporous carbon (meso C) from double comb copolymer, which can serve as excellent counterelectrode for ssDSSCs showing great promise to replace Pt. Co₉S₈ with high catalytic active nature is synthesized via the hydrothermal method. Meso C with a high surface area is obtained by the carbonization of the PVDC-g-POEM double comb copolymer. The structural and morphological characterization of the Co₉S₈ /meso C revealed well defined crystalline nanostructure of Co₉S₈ uniformly embedded on the surfaces of the meso C. The photoelectrochemical characterization suggests that the use of the Co₉S₈/meso C nanostructure enhances the efficiency of the reduction of I₃⁻ to 3I⁻ at the counterelectrode/solid state electrolyte interface. The ssDSSCs assembled with the Co₉S₈ /meso C showed an enhanced solar energy conversion efficiency comparable to a conventional Pt. The enhanced solar energy conversion efficiency of Co₉S₈/meso C could be attributed to the high catalytic active nature and improved electrochemical surface area. In addition, because of the robust structure of Co₉S₈/meso C counterelctrode based on ssDSSCs maintains 90% efficiency at least for 10 day.