Regensburg 2016 – scientific program
DS 48: Oxide Semiconductors for Device and Energy Applications II
(Joint session of DS and HL, organized by DS)
DS 48.4: Talk
Thursday, March 10, 2016, 15:45–16:00, H11
TiO2 laminated Silicon microstructures based stable photocathode for water splitting — •Chittaranjan Das1, Massimo Tallarida2, and Dieter Schmeisser3 — 1Angewantde Physik / Sensorik ,BTU Cottbus-Senftenberg, Germany — 2ALBA-Barcelona — 3Angewantde Physik / Sensorik ,BTU Cottbus-Senftenberg, Germany
The photoelectrochemical (PEC) water splitting is one of the most efficient ways to obtain hydrogen from water using solar power which can be used as carbon free fuel. The PEC device can bedesigned using semiconducting material that will convert solar radiation to H2. Silicon can be one of the best choices for PEC due to its success in solar cells technology. There are certain issues with Si such as stability in electrochemical medium  and higher surface reflectance (25%) which limits the Si as an ideal candidate for PEC technique .
In the present work we addressed these issues by surface structuring and laminating the surface with metal oxide. The microstructuring of Si was done by electrochemical method. The Si microstructure photocathode was stabilized by thin layer of ALD grown TiO2 film. The microstructuring and lamination of Si photocathode by ALD layer of TiO2 decreased the reflectance ofthe surface and shift the onset potential towards anodic direction by 350 mV with a prolonged stability over 60 hours.
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