Solar-driven conversion of water or reduction of CO2 to chemical fuels promises an alternative renewable source of energy. Major advancements have been made in improving the efficiencies and product selectiveness of currently known photocatalysts, nonetheless, a need for rational materials discovery has been noted by the community as a step towards economical industrial application. In our group, we perform first-principles simulations based exploratory searches of materials that can be easily synthesized, are robust in the highly reducing or oxidizing conditions, can harvest solar light and present a wide range of electronic properties suited for extracting competing products. Current efforts are directed towards the design of co-catalysts and tandem photocatalysts that promise spontaneous separation of electrons and holes; and at the same time an immunity towards corrosion-degradation.