Tantalate-based Perovskite for Solar Energy Applications

Abstract

To realize a sustainable society in the near future, the development of clean, renewable, cheap and sustainable resources and the remediation of environmental pollutions using solar energy as the driving force would be important. During the past few decades, plenty of efforts have been focused on this area to develop solar light active materials to meet the increased energy and environmental crisis. Owning to the unique perovskite-type structure, tantalate-based semiconductors with unable chemical composition show high activities toward the conversion of solar radiation into chemical energy. Moreover, various engineering strategies, including crystal structure engineering, electronic structure engineering, surface/interface engineering, co-catalyst engineering and so on, have been developed in order to modulate the charge separation and transfer efficiency, optical absorption, band gap position and photochemical and photophysical stability, which would open a realm of new possibilities for exploring novel materials for solar energy applications.Keywords: Tantalate, photocatalysis, solar energy, perovskite . IntroductionIn view of global energy crisis and environmental pollution, the search for renewable and clean energy resources and the development of eco-friendly systems for environmental remediation have received great attention. Solar energy is the prime renewable source of energy for every life on the earth. The amount of solar energy that strikes the Earth yearly in the form of sunlight is approximately ten thousand times the total energy that is consumed on this planet [ ]. However, sunlight is diffuse and intermittent, which impedes its collecting and storage that play critical roles in the full exploitation of its potentials. As one of the most promising solutions for storing and converting solar energy, semiconductor photocatalysis has attracted much © 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. attention, since it provides an environmental benign strategy for splitting water into hydrogen and oxygen, reducing carbon dioxide into useful chemicals and fossil fuels, and completely eliminating all kinds of contaminants under the sunlight illumination under ambient conditions [ -]. Generally, the fundamental principles of semiconductor photocatalysis have been extensively reported in previous works [ ]. A photocatalytic reaction is initiated on the basis of the formation of photogenerated charges such as electrons and holes after capture of sunlight by a semiconductor. Consequently, electrons can transit from valence band VB to conduction band CB leaving behind holes in the VB. If the photogenerated electron-hole pairs' separation is maintained, the photogenerated carriers can move to the semiconductor surfaces to react with the adsorbed small molecule...

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