气候变化领域集成服务门户(CCPortal): Enhanced stability of silicon for photoelectrochemical water oxidation through self-healing enabled by an alkaline protective electrolyte

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DOI	10.1039/d0ee02250k
	Enhanced stability of silicon for photoelectrochemical water oxidation through self-healing enabled by an alkaline protective electrolyte
	Fu H.J.; Moreno-Hernandez I.A.; Buabthong P.; Papadantonakis K.M.; Brunschwig B.S.; Lewis N.S.
发表日期	2020
ISSN	17545692
起始页码	4132
结束页码	4141
卷号	13 期号:11
英文摘要	Alkaline electrolytes impede the corrosion of Si photoanodes under positive potentials and/or illumination, due to the formation of a SiOx layer that etches 2-3 orders of magnitude more slowly than Si. Hence during water oxidation under illumination, pinholes in protection layers on Si photoanodes result in the local formation of a protective, stabilizing passive oxide on the Si surface. However, operation under natural diurnal insolation cycles additionally requires protection strategies that minimize the dark corrosive etching rate of Si at pinholes. We show herein that addition of [Fe(CN)6]3- to 1.0 M KOH(aq) results in a self-healing process that extends the lifetime to >280 h of an np+-Si(100) photoanode patterned with an array of Ni catalyst islands operated under simulated day/night cycles. The self-healing [Fe(CN)6]3- additive caused the exposed Si(100) surface to etch >180 times slower than the Si etch rate in 1.0 M KOH(aq) alone. No appreciable difference in etch rate or facet preference was observed between Si(100) and Si(111) surfaces in 1.0 M KOH(aq) with [Fe(CN)6]3-, indicating that the surface conformally oxidized before Si dissolved. The presence of [Fe(CN)6]3- minimally impacted the faradaic efficiency or overpotential of p+-Si/Ni electrodes for the oxygen-evolution reaction. © The Royal Society of Chemistry.
英文关键词	Corrosion protection; Electrolytes; Etching; Oxidation; Potassium hydroxide; Self-healing materials; Silicon compounds; Alkaline electrolytes; Enhanced stability; Faradaic efficiencies; Orders of magnitude; Photoelectrochemical water oxidation; Positive potential; Protection strategy; Self-healing process; Silicon; additive; catalyst; corrosion; electrochemical method; electrode; electrolyte; insolation; oxidation; silicon
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/189468
作者单位	Division of Chemistry and Chemical Engineering, 127-72, California Institute of Technology, Pasadena, CA 91125, United States; Division of Engineering and Applied Sciences, California Institute of Technology, Pasadena, CA 91125, United States; Beckman Institute Molecular Materials Research Center, California Institute of Technology, Pasadena, CA 91125, United States
推荐引用方式 GB/T 7714	Fu H.J.,Moreno-Hernandez I.A.,Buabthong P.,et al. Enhanced stability of silicon for photoelectrochemical water oxidation through self-healing enabled by an alkaline protective electrolyte[J],2020,13(11).
APA	Fu H.J.,Moreno-Hernandez I.A.,Buabthong P.,Papadantonakis K.M.,Brunschwig B.S.,&Lewis N.S..(2020).Enhanced stability of silicon for photoelectrochemical water oxidation through self-healing enabled by an alkaline protective electrolyte.Energy & Environmental Science,13(11).
MLA	Fu H.J.,et al."Enhanced stability of silicon for photoelectrochemical water oxidation through self-healing enabled by an alkaline protective electrolyte".Energy & Environmental Science 13.11(2020).