Computational Model of Domain-Specific Reactivity on Coated Ferroelectric Photocatalysts

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• 作者：James J. Glickstein ; Paul A. Salvador ; Gregory S. Rohrer
• 刊名：Journal of Physical Chemistry C
• 出版年：2016
• 出版时间：June 16, 2016
• 年：2016
• 卷：120
• 期：23
• 页码：12673-12684
• 全文大小：564K
• 年卷期：0
• ISSN：1932-7455

文摘

The optimization of coated ferroelectric photocatalysts represents a promising pathway toward competitive efficiencies. Here, we present a computational model that is used to predict the internal quantum efficiency (IQE) of individual coated ferroelectric domains. Criteria are identified that enable increased efficiencies. The net current favored on a negatively polarized domain of BaTiO₃ coated with a 20 nm TiO₂ (anatase) film is shown to be oxidation, whereas reduction is favored on positively polarized coated BaTiO₃ domains. The results indicate that the IQE of the minority carrier reaction (oxidation) at physical conditions reported in the literature is less than 1%. By increasing the carrier lifetime to approximately 100 ns, increasing the reduction reaction kinetics, and optimizing the potential, complementary electron and hole reactions of equal magnitude can occur separately on positive and negative domains with an IQE of over 90% (45% if operated in a Z-scheme). This analysis can be applied to heterostructured photocatalysts with various sources of charge-separating internal fields, including those that also absorb visible light, to ultimately maximize the solar to hydrogen efficiency.