Photoelectrocatalytic application of vanadylporphyrin complexes directly extracted from oil

Abstract

Non-pure primary Vanadyl petroporphyrins extracted from oil, i.e., PVP(Oil), have been impregnated on SBA-15 or on SiO2. For comparison, synthetic vanadyl octaethylporphine, VP(S), was also impregnated on the same siliceous materials. The characterization result of unsupported porphyrins and the catalysts, by FTIR and DR-UV-vis, confirm the successful incorporation of the corresponding vanadyl porphyrins. Electrochemical and photoelectrochemical properties of these catalysts have been evaluated through Electrochemical Impedance Spectroscopy (EIS), Mott-Schottky (MS) and voltammetry tests. According to the results, primary vanadyl porphyrin extracted from oil, PVP(Oil), show better photoelectrochemical response, regardless of the support used (either SiO2 or SBA15), than synthetic ones, VP(S). Additionally, this study reveals that PVP(Oil) can be used as photoelectrocatalysts for methyl red (MR) degradation (a common organic dye), showing almost a complete degradation of (MR) using PVP(Oil)-SBA15 catalyst after 3 h. Interestingly, an increase of more than 25% in the kinetic constant for the photoelectrochemical degradation of MR is shown for the PVP(Oil) in comparison to the VP(S).