Innovatively Designed Chalk-Shaped CdS@ACC Nanocomposite Photocatalyst-Enzyme Attached Artificial Photosynthesis Reactor for Production of Formic Acid from CO₂

The unceasing global energy demand along with increasing global warming and pollution has ignited the scientific community to develop several innovations. This work is concerted on the development of a bio-photocatalytic system that can utilize CO₂ and produce formic acid which itself has a wide application in fuel cells. Herein, we design a graphene-based visible light active photocatalyst i.e., CdS@ACC nanocomposite that was synthesized by using hydrothermal method at different concentration of photocatalyst (CdS/ACC mass ratio = 5wt% CdS/ACC, 10wt% CdS/ACC, 15wt% CdS/ACC, and 20wt%CdS/ACC), for comparing their photocatalytic performance. The photocatalyst CdS@ACC showed an appropriate band gap and a high molar absorbance coefficient which reflected its efficient photocatalytic activity. The photocatalyst CdS@ACC efficiently showed 43.25% 1,4 NADH regeneration in 1 h and when this photocatalyst was coupled with a biological enzyme i.e., formate dehydrogenase, the system successfully produced 116.23µM of HCOOH in 1 h. This work focusses on the formation and application of an innovatively designed chalk-shaped CdS@ACC nanocomposite artificial photosynthesis system for carbon dioxide fixation to solar fuel.