The Water Oxidation Bottleneck in Artificial Photosynthesis: How Can We Get Through It? An Alternative Route Involving a Two-Electron Process

The state-of-the-art of research on artificial photosynthesis is briefly reviewed. Insights into how Nature takes electrons from water, the photon-flux density of sunlight, the time scale for the arrival of the next photon (electron-hole) at the oxygen-evolving complex, how Nature solves the photon-flux-density problem, and how we can get through the bottleneck of water oxidation are discussed. An alternate route for a two-electron process induced by one-photon excitation is postulated for getting through the bottleneck of water oxidation.