90% of our commodity chemicals and fuels are made from thermocatalysis industries driven by heat or grid power. In the context of carbon-neutral society, sunlight-driven photocatalysis is an ideal alternative to thermocatalysis especially for CO2 and H2O utilization. However, how to scale the lab-scale photocatalysis into real industry remains uncertain. To amplify, the efficiency of photocatalysis not only rely on the temperature related reaction rates but also the utilization of charge carriers, which requires simultaneous optimization of quantum yield and light transport. The challenges lie in photocatalyst and photoreactor engineering to use every incident photon reaching every catalytic site while minimizing parasitic absorption, reflection, scattering, transmission, and thermal conductive, convective, and radiative losses. See full story at Advanced Science News.