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DOI	10.1039/c9ee00452a
	Artificial inflation of apparent photocatalytic activity induced by catalyst-mass-normalization and a method to fairly compare heterojunction systems
	Kunz L.Y.; Diroll B.T.; Wrasman C.J.; Riscoe A.R.; Majumdar A.; Cargnello M.
发表日期	2019
ISSN	17545692
起始页码	1657
结束页码	1667
卷号	12 期号:5
英文摘要	Despite the potential of using photocatalysts to sustainably produce fuels and chemicals, overall reaction rates remain prohibitively low, largely limited by recombination of photogenerated electrons and holes. Past research on suppressing this recombination by the addition of co-catalysts or by the formation of heterojunctions has led to claims that rates show enhancement compared to the single-component, junction-free counterparts. However, comparing these systems is rendered difficult by the common practice of reporting rates on a catalyst mass basis. Using a model system of TiO2 and g-C3N4 with Pt, here we show that normalizing photocatalytic rates by mass fails to provide mechanistic insight and can also artificially inflate the apparent performance of heterojunction systems - in our case, overestimating the enhancement by 24 ± 7%. This effect is caused by the nonlinearity of light absorption with respect to the concentration of each light-absorbing component, according to Beer's law. This factor needs to be taken into account to verify if improvements in absolute activity correspond to intrinsic activity. To this end, a method is presented for approximating a system quantum yield from measured reaction rates under simulated solar or otherwise polychromatic light. A sensitivity analysis provides guidelines for reducing the artificial enhancement introduced by mass-normalization for any heterojunction system. © 2019 The Royal Society of Chemistry.
英文关键词	Catalyst activity; Heterojunctions; Light absorption; Photocatalytic activity; Platinum compounds; Sensitivity analysis; Titanium dioxide; Absorbing components; Co catalysts; Intrinsic activities; Overall reactions; Photocatalytic rate; Photogenerated electrons; Polychromatic lights; Single components; Reaction rates; absorption; adsorption; catalyst; heterogeneity; light intensity; nonlinearity; photochemistry; reaction kinetics; sensitivity analysis
语种	英语
来源期刊	Energy & Environmental Science
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/189911
作者单位	Department of Chemical Engineering, SUNCAT Center for Interface Science and Catalysis, Stanford University, Stanford, CA 94305, United States; Center of Nanoscale Materials, Argonne National Laboratory, Lemont, IL 60439, United States; Department of Mechanical Engineering and Precourt Institute for Energy, Stanford University, Stanford, CA 94305, United States; Department of Chemical Eng., SUNCAT Center for Interface Science and Catalysis, Stanford University, Stanford, CA 94305, United States
推荐引用方式 GB/T 7714	Kunz L.Y.,Diroll B.T.,Wrasman C.J.,et al. Artificial inflation of apparent photocatalytic activity induced by catalyst-mass-normalization and a method to fairly compare heterojunction systems[J],2019,12(5).
APA	Kunz L.Y.,Diroll B.T.,Wrasman C.J.,Riscoe A.R.,Majumdar A.,&Cargnello M..(2019).Artificial inflation of apparent photocatalytic activity induced by catalyst-mass-normalization and a method to fairly compare heterojunction systems.Energy & Environmental Science,12(5).
MLA	Kunz L.Y.,et al."Artificial inflation of apparent photocatalytic activity induced by catalyst-mass-normalization and a method to fairly compare heterojunction systems".Energy & Environmental Science 12.5(2019).