Photo‐induced hydrogen on iron hexagonal mesoporous silica (Fe‐HMS) photo‐catalyst. (6th July 2011)

• Record Type: Journal Article
• Authors: Boudjemaa, Amel; Bachari, Khaldoun; Trari, Mohamed
• Is Part Of: International journal of energy research. Volume 37:Number 2(2013:Feb.)
• Page Start: 171
• Page End: 178
• Publication Date: 2011-07-06
• Subjects: Power resources -- Periodicals; Power (Mechanics) -- Periodicals; Power resources -- Research -- Periodicals; 621.042
• DOI: 10.1002/er.1880
• Languages: English
• ISSNs: 0363-907X

Abstract

<abstract abstract-type="main"> <title>SUMMARY</title> <p>The iron hexagonal mesoporous silica (Fe‐HMS)‐<italic>n</italic> photocatalyst, where n is the molar ratio Si/Fe in the precursor gel (=50), has been successfully synthesized at an ambient temperature using hexadecylamine as template agent. The material was characterized by X‐ray diffraction, N<sub>2</sub> adsorption measurement Brunauer, Emmet, Taller (BET) and Barrett–Joyner–Halenda theory, UV–Vis spectroscopy, high‐resolution transmission electron microscopy and electron spin resonance. The electrical conductivity follows an Arrhenius‐type law with activation energy of 0.04 eV. Fe<sub>2</sub>O<sub>3</sub> is uniformly dispersed on the HMS surface; it works synergistically to make Fe‐HMS photoelectrochemically active. The flat band potential (−0.75 V<sub>SCE</sub>) is higher than the potential of hydrogen generation (−0.50 V<sub>SCE</sub> at pH~7), and the material shows high efficiency for hydrogen evolution upon visible light. The photoactivity in Na<sub>2</sub>SO<sub>4</sub> and Na<sub>2</sub>SO<sub>3</sub> (0.1 M) solution was found to be 136 and 175 µmol g<sup>‐1</sup> min<sup>‐1</sup>, respectively under full light (29 mW cm<sup>‐2</sup>). The tendency to saturation, observed only in SO<sub>3</sub><sup>2‐</sup> electrolyte, is ascribed to the competitive reduction of the end product, namely S<sub>2</sub>O<sub>6</sub><sup>2‐</sup> with the water reduction. Copyright © 2011 John Wiley & Sons, Ltd.</p> </abstract>