TiO2 is already a well-studied photocatalytic material because of its excellent properties such as chemical stability, low price and non-toxicity. However, the fact that its band gap (3,2 eV) allows it to absorb only the UV light limits its use. On the other hand, the SnS2 (band gap ~2,2 eV) absorption range is well within the visible light spectrum, which is more suitable for solar harvesting. Both of these materials yield rapidly recombining electron-hole pairs upon photoexcitation. This recombination can be prevented by the addition of hole scavengers, which increase the survival probability of the electrons. Over the years there have been various efforts to improve such reaction efficiency using different hole scavengers. This work was focused on the influence of ascorbic acid (AA) on the photoelectrochemical response of TiO2 and SnS2 [1].The obtained results indicated that by using an AA solution photocurrents response significantly increases confirming its good hole scavenging properties. Additionally, it was shown that by increasing AA concentration from 10 mM to 100 mM TiO2 photoactivity was not improved while SnS2 photoactivity significantly increased. The photoactivity was determined by using linear sweep voltammetry, electrochemical impedance spectroscopy and open circuit potential monitoring. The interaction of AA and metal oxide was studied by UV/Vis spectroscopy. [1] A. Indra, R. Beltrán-Suito, M. Müller, R.P. Sivasankaran, M. Schwarze, A. Acharjya, B. Pradhan, J. Hofkens, Promoting Photocatalytic Hydrogen Evolution Activity of Graphitic Carbon Nitride with Hole-Transfer Agents, ChemSusChem, 14, (2020), 306-312, doi: https://doi.org/10.1002/cssc.202002500 This research has been supported by European Structural and Investment Funds , Water Purification and Energy Conversion using Novel Composite Materials and Solar Irradiation , KK.01.1.1.04.0001 and Croatian Science Foundation under the project NaSCEnT (IP-2018-01-1982).
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