Photocatalysis solar systems

There is clearly a growing interest in photocatalysis involving metal hydrides (see Section VIII) and hydrogenase systems (see Section IX), and the search for systems to utilize solar energy to dissociate water into its elements will undoubtedly intensify further efforts. 

Another important photocatalytic application is the synthesis of hydrogen from water. However, low solar efficiency and photocorrosion have proven to be hindrances limiting the process economics of photocatalysis [325], The most efficient systems to date consist of compound semiconductor heterostructures that operate with efficiencies of approximately 16%, however, cost and stability are still problematic [325],... 

Most of the efforts of researchers, working in the field of semiconductor colloids, are directed to the chemical modification of the system to make photoproduction reactions more efficient. EPR spectroscopy will certainly contribute to the development of new nanoscale materials which can effectively undergo charge separation for wide application in photocatalysis and solar energy conversion. 

The predictions concerning PL presented earlier (Anpo and Che, 1999) (applications to a broader range of systems, such as sulfides, (oxi)car-bides, (oxi)nitrides time-resolved equipment for in-depth investigation of excited states increased attention to solar energy and photocatalysis related to environmental problems) are still largely valid. 

Photo-initiated AOPs are subdivided into VUV and UV oxidation that are operated in a homogeneous phase, and in photocatalysis (Fig. 5-15). The latter can be conducted in a homogeneous aqueous phase (photo-enhanced Fenton reaction) or in a heterogeneous aqueous or gaseous phase (titanium dioxide and certain other metal oxide catalysts). These techniques apply UV-A lamps or solar UV/VIS radiation and they are in pre-pilot or pilot status. According to Mukhetjee and Ray (1999) the development of a viable and practical reactor system for water treatment with heterogeneous photocatalysis on industrial scales has not yet been successfully achieved. This is mainly related to difficulties with the efficient distribution of electromagnetic radiation (UV/VIS) to the phase of the nominal catalyst. 

Arthur J. Nozik is a senior research fellow with the Basic Science Division of the National Renewable Energy Laboratory (NREL). He received his B.S.Ch. from Cornell University in 1959 and his M.S. in 1962 and his Ph.D. in 1967 in physical chemistry from Yale University. Since receiving his Ph.D., Dr. Nozik has worked at NRL, where he has conducted research in nanoscience, photoelectrochemistry, photocatalysis, and hydrogen energy systems. He has served on numerous scientific review panels and received several awards in solar energy research. He is a senior editor of the Journal of Physical Chemistry, a fellow of the American Physical Society, and a member of the American Chemical Society, the American Association for the Advancement of Science, the Materials Research Society, the Society of Photo Optical Instrument Engineers, and the Electrochemical Society. 

The future of solar energy An interdisciplinary MIT study, 2015. Available from https //mitei.mit.edu/system/files/MIT%20 Fu-ture%20of%20Solar%20Energy%20Study compressed.pdf Linseblinger, A. L. Lu, G. Yates, J.T. Photocatalysis on Ti02 Surfaces Principles, Mechanisms, and Selected Results. Chem.Rev. 1995, 95, 735-758. 

In spite of the remarkable development of the photoenergy conversion research field, it is still difficult to establish an artificial photosynthetic system creating energy resources from solar energy by utilizing photocatalysis. In this chapter, we describe some photocatalytic reactions that may lead to artificial photosynthetic systems and solar cells. 

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