In 2010, we initialized a breakthrough of using new electrolyte systems for DSC, which is now a fast growing activity worldwide. We discovered that an org. tri-arylamine type dye, with bulky alkoxy donor groups to prevent recombination losses, gives high efficiencies (6.7%) with Co-complex based redox couples. Recently Gratzel's group has taken the DSC world record of 12.3% using our Co-based electrolytes and dye systems. Using the same device concept as for DSC we have developed a photoelectrochem. device with a mol. Ru catalyst adsorbed, via a Nafion membrane, on a nanostructured TiO2 film as anode and a Pt foil as cathode. This system has been successfully demonstrated to split water into O2 and H2 driven by visible light. In another system we have demonstrated a mol. device with a photocathode for hydrogen generation based on p-type semiconductor NiO, an org. dye and a cobalt catalyst.