Visible light driven photocatalytic hydrogen evolution using different sacrificial reagents

In this work the photocatalytic hydrogen production from aqueous solution containing organic compounds, using perovskite based photocatalyst supported on magnetic particles, was studied. In particular a photocatalyst based on Ru doped LaFeO3 was used. The photocatalyst was prepared by solution combustion synthesis using citric acid as organic fuel, and it was characterized by different techniques, such as XRD, UV-Vis DRS and Raman spectroscopy. This semiconductor has shown photocatalytic activity in presence of visible light and it was supported on Fe2O3 magnetic particles in order to remove it easily at the end of the process. The Fe2O3 particles were prepared by combustion flame synthesis, using citric acid as organic fuel and metal nitrate as iron oxide precursor. The Ru-LaFeO3 photocatalyst was coupled with magnetic Fe2O3 particles by a physical mixture in order to ensure a tight contact between the two solid phases (Ru-LaFeO3/Fe2O3). Photocatalytic tests were carried out in a pyrex cylindrical reactor equipped with a N2 distributor device and irradiated by visible-LEDs. Different aqueous solution containing organic compounds such as ethanol, glycerol or methanol were tested. The experimental results evidenced that the higher hydrogen production (about 10000 μmol L-1 after 4 h of irradiation time) was obtained in presence of methanol. The magnetic composite showed a very high stability also after several reuse cycles