Cobalt Phosphate Group Modified Hematite Nanorod Array As Photoanode for Efficient Solar Water Splitting

Wednesday, 27 May 2015: 15:20
Williford Room C (Hilton Chicago)
L. Fu (Dalian Institute of Chemical Physics), H. Yu (Chinese Academy of Sciences, Dalian Institute of Chemical Physics), C. Zhang (Dalian Institute of Chemical Physics, zhangchk@dicp.ac.cn), Z. Shao, and B. Yi (Dalian Institute of Chemical Physics)
Hydrogen production by photoelectrochemical water splitting based on modified nanostructure hematite is investigated for transformation and store of solar energy. Herein, nanorod hematite arrays were prepared by adjusted-hydrothermal method with a diameter of 30 nm. Phosphate group and cobalt ions were deposited of the surface of hematite by chemical immersion process to improve its photoelectrochemical performance and speed up the oxygen revolution reaction in water splitting. The CoPi-modified α-Fe2O3 nanorod arrays (NAs) showed a greatly enhanced electrochemical and photoelectrochemical property with a photocurrent density 270 μA/cm2 at 1.23V (vs. RHE) for FeCoPi-4 compared with 20 μA/cm2 for untreated α-Fe2O3 NAs. The effect of phosphate groups and cobalt ions on the α-Fe2O3 NAs were both investigated. The Co(Ⅱ) ion is connected closely with the α-Fe2O3 surface through phosphate groups by XPS detection. The phosphate enhances the transport of electron from the α-Fe2O3 to Co ion. The high performance domanstrated in photoelectrochemical test indicates that CoPi-modified α-Fe2O3 NAs is a potential photoelectrocatalyst for water splitting.