Article

Water Splitting on Semiconductor Catalysts under Visible-Light Irradiation

Instituto de Catálisis y Petroleoquímica, CSIC, Madrid, Spain.
ChemSusChem (Impact Factor: 7.66). 07/2009; 2(6):471-85. DOI: 10.1002/cssc.200900018
Source: PubMed

ABSTRACT

Sustainable hydrogen production is a key target for the development of alternative, future energy systems that will provide a clean and affordable energy supply. The Sun is a source of silent and precious energy that is distributed fairly all over the Earth daily. However, its tremendous potential as a clean, safe, and economical energy source cannot be exploited unless the energy is accumulated or converted into more useful forms. The conversion of solar energy into hydrogen via the water-splitting process, assisted by photo-semiconductor catalysts, is one of the most promising technologies for the future because large quantities of hydrogen can potentially be generated in a clean and sustainable manner. This Minireview provides an overview of the principles, approaches, and research progress on solar hydrogen production via the water-splitting reaction on photo-semiconductor catalysts. It presents a survey of the advances made over the last decades in the development of catalysts for photochemical water splitting under visible-light irradiation. The Minireview also analyzes the energy requirements and main factors that determine the activity of photocatalysts in the conversion of water into hydrogen and oxygen using sunlight. Remarkable progress has been made since the pioneering work by Fujishima and Honda in 1972, but he development of photocatalysts with improved efficiencies for hydrogen production from water using solar energy still faces major challenges. Research strategies and approaches adopted in the search for active and efficient photocatalysts, for example through new materials and synthesis methods, are presented and analyzed.

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    • "Photocatalytic hydrogen evolution over different g-C 3 N 4 samples -either alone or loaded with 1.0 wt.% of Pt-was evaluated under visible light irradiation (>465 nm) using triethanolamine (TEA) as a scavenger, at room temperature and atmospheric pressure following a procedure similar to a previously reported method [13]. Prior to catalyst testing, blank experiments showed that no reaction occurs when the system was illuminated in the absence of catalyst or in the presence of catalyst without illumination. "
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    • "Hydrogen, an attractive clean energy source with high energy capacity, is a very promising candidate as a primary energy source in the future [1] [2]. Photocatalytic water splitting is considered as an alternative method to produce hydrogen utilizing solar energy. "
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