The Preparation Of Light-induced Water-splitting Devices Using Cobalt-oxide Modified Photoanodes

Artific ial Photosyhthesis for hydrogen production, directly transforming solar energy to chemical energy, is an effective way to solving issues like energy shortage and environment pollution in the 21 t h century. Visible- light- induced water splitting devices can make the dream accessible by accomplishing water-oxidation and proton- reduction on photoanodes and photocathode respectively. Between the two reaction, water-oxidation is extremely complicated, which has been the bottle- neck of the light- induced-water-splitting research. And the key to overcome the barrier is to develop highly effective catalysts. Recently, catalysts based on Ru, Ir and other noble metal elements have showed excellent ability for water oxidation. However, there high cost hider the further practical application. Thus, it is necessary to do research on earth- abundant metal based catalysts.In this study, phosphate group functionalized tri-bipyridyl Ruthenium complex was used as photosensitizer. Small sized Co3O4 nanoparticals were synthesized and used as water-oxidation catalysts. Flexible long chains were used to get the C o3O4 nanoparticals adsorbed on the dye-sensitized photoanodes. Water splitting devices were also prepared for photoelectric properties test. The highest photocurrent density is up to 140μA/cm2 when add the catalysts and only 15μA/cm2 without the catalysts.Moreover, bio- mimetic electron transfer mediator as Tyz- His190 group in photosystemⅡ was synthesized and induced to the surface of p hotoanodes. The devices prepared from these p hotoanodes showed more photocurrent density enhancement and much less decay, keeping steady after 90s’ illumination.