Abstract
If artificial fixation schemes are to be successful reducing the atmospheric carbon dioxide concentration, they must operate at rates which far exceed those of current natural sinks. Photocatalytic and electrocatalytic CO2 reduction will be described in this context. Semiconductor-based photocatalyst CO2 reduction is conceptually simple but has struggled to exceed natural photosynthesis in conversion efficiency. I will show that optimization of mass transfer and control of the catalytic microenvironment addresses this challenge by increasing conversion rates by over an order of magnitude. New sulfide-based photoelectrocatalytic materials are showing promise as CO2 reduction photocathodes. Finally, I will show that the chemical reaction network of electrocatalytic CO2 reduction is highly dynamic and can have many of the functionalities found in biological networks such as inhibition/activation, cascades, and substrate channeling/pre-concentration.