High Quality Content by WIKIPEDIA articles! Photocatalytic water splitting is the term for the production of hydrogen (H2) and oxygen (O2) from water by directly utilizing the energy from light. Hydrogen fuel production has gained increasing attention as oil and other nonrenewable fuels become increasingly depleted and expensive. Methods such as photocatalytic water splitting are being investigated to produce hydrogen fuel, which burns cleanly and can be used in a hydrogen fuel cell. Water splitting holds particular interest since it utilizes the inexpensive natural resource water. Photocatalytic water splitting has the simplicity of using a powder in solution and sunlight to produce H2 and O2 from water and can provide a clean, renewable energy source, without producing greenhouse gases or having many adverse effects on the atmosphere. Theoretically, only solar energy (photons), water and a catalyst are needed.