Hydrogen, as a kind of green renewable energy, can greatly alleviate the current energy crisis and environmental pollution problems. As the focus and front of scientific research, splitting of water into hydrogen and oxygen by solar energy is considered to be one of the most ideal means to obtain the hydrogen energy. However, the oxygen evolution reaction (OER) is more difficult to occur, which greatly limits the application of water splitting. This is because OER is a 4 electron transfer reaction with a higher reaction barrier, requiring additional over-potential to drive the reaction. The additional over-potential will cause higher efficiency loss, thus reducing the practicability of the water splitting. The ideal OER catalyst should have an appropriate band gap, high efficiency in converting solar energy, chemical inertness and reduces the consumption of precious metals.