Renewable energy resources (such as solar, wind, or tidal) are considered as the best option for replacing the current carbon-based fuel economy. However, the intermittent nature of those renewable energy resources has restricted their practical application. In our lab, we are interested to follow a natural photosynthesis-inspired strategy where renewable energy resources can be stored in chemical energy. Here, we are mostly focusing on solar-driven small molecule activation reactions such as hydrogen evolution reaction (HER), oxygen reduction reaction (ORR), and water oxidation reaction (WOR). For this purpose, we develop first-row transition metal-based molecular catalysts that include the vital architectural features of natural metalloenzymes. Apart from chemical synthesis, we perform electrochemistry and photocatalysis in both homogeneous and heterogeneous conditions.