Synthesis of Sugar and fixation of CO2 through Artificial Photosynthesis driving by Hydrogen or Electricity

Abstract: The overall process of photosynthesis consists of two main phases, the so-called light and dark eactions: light energy is absorbed by chlorophyll molecules and transferred to regenerate NADH and ATP, then drive Calvin-Benson cycle to synthesize sugar. In order to synthesize sugar through artificial photosynthesis, one of the key is to regenerate ATP economically and improve the efficiency of dark reactions. Here 9 kinds of dark reaction pathways are proposed, which only NADH is regenearated from hydrogen or electricity for driving, the efficiency of dark reactions is improved, combined with solar photovoltaic or solar hydrogen technology, the total efficiency of artificial photosynthesis can reach 30%, several ten times more than natural photosynthesis. One of them, to use chemical synthesis of formaldehyde from CO2 and H2, no NADH and ATP is need, to synthesize sugar efficiently through 9 enzymes, so it will be easier to produce in large scale, and the sugar will be a good energy carrier as the sugar can be efficiently converted to energy carrier hydrogen through enzymes.