Methylene Blue Dye as Photosensitizer for Scavenger-Less Water Photo Splitting: New Insight in Green Hydrogen Technology

In this study, hydrogen generation was performed by utilizing methylene blue dye as visible-light photosensitizer while the used catalyst is working as a transfer bridge for the electrons to H<sup>+</sup>/H<sub>2</sub> reaction. Silica NPs-incorporated TiO<sub>2</sub...

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Bibliographic Details
Main Authors: Nasser A. M. Barakat, Gehan M. K. Tolba, Khalil Abdelrazek Khalil
Format: Article
Language:English
Published: MDPI AG 2022-01-01
Series:Polymers
Subjects:
Online Access:https://www.mdpi.com/2073-4360/14/3/523
Description
Summary:In this study, hydrogen generation was performed by utilizing methylene blue dye as visible-light photosensitizer while the used catalyst is working as a transfer bridge for the electrons to H<sup>+</sup>/H<sub>2</sub> reaction. Silica NPs-incorporated TiO<sub>2</sub> nanofibers, which have a more significant band gap and longer electrons lifetime compared to pristine TiO<sub>2</sub>, were used as a catalyst. The nanofibers were prepared by electrospinning of amorphous SiO<sub>2</sub> NPs/titanium isopropoxide/poly (vinyl acetate)/N, N-dimethylformamide colloid. Physicochemical characterizations confirmed the preparation of well morphology SiO<sub>2</sub>–TiO<sub>2</sub> nanofibers with a bandgap energy of 3.265 eV. Under visible light radiation, hydrogen and oxygen were obtained in good stoichiometric rates (9.5 and 4.7 mL/min/gcat, respectively) without any considerable change in the dye concentration, which proves the successful exploitation of the dye as a photosensitizer. Under UV irradiation, SiO<sub>2</sub> NPs incorporation distinctly enhanced the dye photodegradation, as around 91 and 94% removal efficiency were obtained from TiO<sub>2</sub> nanofibers containing 4 and 6 wt% of the used dopant, respectively, within 60 min.
ISSN:2073-4360