262174 Studies On Nanostructured Bilayered Semiconductor System in PEC Water Splitting for Hydrogen Production

Wednesday, October 31, 2012: 1:10 PM
307 (Convention Center )
Surbhi Choudhary1, Sumant Upadhyay1, Pushpendra Kumar1, Nirupama Singh1, Vibha Rani Satsangi2, Rohit Shrivastav1 and Sahab Dass1, (1)Department of Chemistry, Dayalbagh Educational Institute, Agra, India, (2)Department of Physics and Computer Science, Dayalbagh Educational Institute, Agra, India

Studies on Nanostructured Bilayered Semiconductor System in PEC Water Splitting for Hydrogen Production

Surbhi Choudhary1, Sumant Upadhyay1, Pushpendra Kumar1, Nirupama Singh1, Vibha R. Satsangi2, Rohit Shrivastav1 and Sahab Dass1*

1Department of Chemistry, Faculty of Science, Dayalbagh Educational Institute, Agra-282110 (India)

2Department of Physics & Computer Sciences, Faculty of Science, Dayalbagh Educational Institute, Agra-282110 (India)

Performance of photo-electrodes in photoelectrochemical (PEC) water splitting for hydrogen production can be improved by fabricating bilayered electrodes consisting of two semiconductors possessing different energy levels for their corresponding conduction and valence band. The small/mid band gap semiconductor is primarily responsible for visible light absorption and sensitizing the large band gap semiconductor through electron and/or hole injection. The energy layers in the bilayered semiconductors can cover visible spectrum thereby offering synergistic effect and better output.

 

In the present study, an attempt has been made to synthesize bilayered SrTiO3 (~3.5 eV) / WO3 (~2.7eV) thin films by sol-gel spin-coating process on conducting glass substrate to explore its application in PEC cell. Prepared thin films were characterized for: (a) crystalline phase by XRD analysis, (b) band gap energy by spectrometric measurement and (c) surface morphology by SEM analysis. Subsequently, SrTiO3/WO3 bilayered film was used in a PEC cell as working electrode having platinum and saturated calomel as counter and reference electrode respectively and 150 W Xenon lamp as light source for illumination. Maximum photocurrent density 0.091 mA/cm2 at 0 V/SCE was observed for bilayered SrTiO3/WO3 thin film photoelectrode which was two folds higher than offered by SrTiO3 (0.046 mA/cm2) and much higher than that for WO3 thin films [Fig. 1]. The enhanced photoelectrochemical behaviour of bilayered photoelectrodes can be attributed to: (a) the extended absorption towards visible region, (b) formation of mixed oxide at the interface and (c) enhanced charge separation of both the materials resulting in decrease of recombination of charge carriers.

                                                                              

Keywords: Photoelectrochemical cell, Heterojunction, Solar energy, Water splitting

 

*Corresponding author: Sahab Dass

  Email: drsahabdas@gmail.com


Extended Abstract: File Uploaded