Photoresponse of Visible Light Active CM-n-TiO2, HM-n-TiO2, CM-n-Fe2O3, and CM-p-WO3 towards Water Splitting Reaction
Figure 4
Photocurrent density, (measured under light intensity of 100 mW cm−2 from a 150 Watt Xenon lamp) as a function of measured potential, (V/SCE), for oven-made n-TiO2 synthesized at 825°C for 16 min (sample 1); CM-n-TiO2 synthesized by only thermal flame oxidation of Ti at 825°C for 16 min (sample 2); grooved CM-n-TiO2 synthesized by only thermal flame oxidation of Ti (0.005 in groove depth) at 820°C for 18 min (sample 3); CM-n-TiO2 synthesized by spray pyrolysis of 0.175 M TiCl4 in ethanol at substrate temperature of 460°C for 20 sec at carrier gas (oxygen) pressure of 20 psi followed by thermal flame oxidation at 825°C for 16 min (sample 4); electrolyte solution of 5 M KOH was used. The electrode potentials at open circuit condition under illumination, , were found to be −0.977 V/SCE (sample 1), −0.940 V/SCE (sample 2), −0.942 V/SCE (sample 3), and −0.915 V/SCE (sample 4) [21–23].
