Hydrogen production using sun light is considered to be one of the most promising alternatives to fossil fuel-derived energy technology. This review presented the study on the photo-electrochemical (PEC) response of hematite (α-Fe2O3 ) by quadrivalent doping results in n-type conductivity. In general, dopants improve the conductivity of hematite thin films. The improved conductivity brought on the incorporation of the dopant is most likely from the n-type lattice substitution of Fe3+ by tetravalent ions, such as Si4+, resulting in a higher electron concentration. This supplementation may be carried out by employing a Tandem cell configuration. This induces a proper direction for the future course of investigations that may lead to an economic, renewable method for environment-friendly hydrogen production.