Water Splitting on Semiconductor Catalysts under Visible‐Light Irradiation

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.

Recent Progress in Metal‐Organic Frameworks for Applications in Electrocatalytic and Photocatalytic Water Splitting

“…Water splitting using photocatalysts has since been widely investigated 74, 75, 76, 77, 78. Previous reviews of water splitting using semiconductors as photocatalysts have demonstrated the basic principles of the water splitting process 76, 77, 78.…”

Origin and Perspectives of the Photochemical Activity of Nanoporous Carbons

“…The photocurrent generated versus the wavelength, PC(λ), for different nanoporous carbon films tested is presented in Figure 8 . It was measured in a broad range of irradiation energy and the carbons' activity, however smaller than that for commercial silicone‐based photovoltaic cell,98, 99 also covered a very broad range of photons energy.…”

Group III-nitride nanowire structures for photocatalytic hydrogen evolution under visible light irradiation

“…To date, metal oxides have been widely explored as a photocatalyst for water-splitting, [15][16][17] which, however, offer the limiting efficiency of ∼2.3% due to their large band-gaps and lack of significant activity under visible light irradiation (∼46% of energy in the solar spectrum). 17,18 Previously reported visible light responsive photocatalysts often suffer from the propensity of oxidation and lack in stability with very limited efficiency in the visible spectrum. 19,20 Moreover, the photocatalytic activity of conventionally used powder samples is low due to their inefficient light absorption and carrier separation, a E-mail: zetian.mi@mcgill.ca.…”