Water splitting is a process that uses renewable energy sources to break down water molecules into oxygen and hydrogen gas. This can be achieved through various methods, such as electrolysis, photocatalysis, and photoelectrochemical cells. The hydrogen gas produced can then be used as a clean and sustainable fuel source for various applications, including fuel cells and transportation. Research in this area focuses on improving the efficiency, cost-effectiveness, and scalability of water splitting technologies to enable widespread adoption of this promising renewable energy solution.