气候变化领域集成服务门户(CCPortal): Evaluating particle-suspension reactor designs for Z-scheme solar water splitting via transport and kinetic modeling

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DOI	10.1039/c7ee01360d
	Evaluating particle-suspension reactor designs for Z-scheme solar water splitting via transport and kinetic modeling
	Bala Chandran R.; Breen S.; Shao Y.; Ardo S.; Weber A.Z.
发表日期	2018
ISSN	17545692
起始页码	115
结束页码	135
卷号	11 期号:1
英文摘要	Sunlight-driven water splitting to produce hydrogen and oxygen provides a pathway to store available solar energy in the form of stable, energy-dense chemical bonds. Here we investigate a tandem particle-suspension reactor design for solar water splitting comprising micron-scale photocatalyst particles suspended in an aqueous solution with soluble redox shuttles. A porous separator facilitates redox species transport between the hydrogen and oxygen evolution reaction compartments while averting gas crossover. A two-dimensional, transient model of the reactor is presented to illustrate the coupling between light absorption, interfacial electron-transfer kinetics and species transport, and their combined impacts on overall solar-to-hydrogen conversion efficiency. The volumetric reactivity of the suspended semiconductor particles is dictated by combining the (photo)current-voltage behavior of a photodiode with Butler-Volmer electron-transfer kinetics. For the first time, a quantitative approach to determine the impacts of surface-dependent redox shuttle kinetic parameters on reaction selectivity in a Z-scheme system is established. Model results provide insights on the effects of optical, transport and kinetic properties of the semiconductor particles and the redox shuttles on the overall reactor performance. Solar-to-hydrogen reactor efficiencies predicted with BiVO4 particles for oxygen evolution are at least two times larger than efficiencies achieved with wider band-gap TiO2 particles due to enhanced visible light absorption; hydrogen evolution with SrTiO3:Rh particles was considered for both cases. Superior performance is predicted with proton-coupled electron transfer redox shuttles (para-benzoquinone/hydroquinone and iodide/iodate) that absorb little-to-no visible light, while also facilitating operation at near-neutral pH conditions, as compared to the non-proton-coupled triiodide/iodide and iron(iii)/iron(ii) redox shuttles. For 1 cm tall reaction compartments, diffusive species transport is fast enough to sustain reactor operation at a 1% solar-to-hydrogen conversion efficiency for both para-benzoquinone/hydroquinone and iodate/iodide redox shuttles with less than 2.2 mg L-1 of each of BiVO4 and SrTiO3:Rh particles in the solution. © The Royal Society of Chemistry.
英文关键词	Bismuth compounds; Bond strength (chemical); Conversion efficiency; Electromagnetic wave absorption; Electron transitions; Energy gap; Hydrogen; Hydrogen bonds; Hydrogen production; Iodine compounds; Iron oxides; Kinetics; Light; Light absorption; Oxygen; Rhodium; Rhodium compounds; Solar energy; Solar power generation; Solutions; Strontium compounds; Strontium titanates; Suspensions (fluids); Titanium compounds; Titanium dioxide; Electron transfer kinetics; Interfacial electron transfer; Oxygen evolution reaction; Proton coupled electron transfers; Quantitative approach; Semiconductor particles; Solar-to-hydrogen conversions; Visible light absorption; Vanadium compounds; aqueous solution; catalyst; design; efficiency measurement; electron; instrumentation; performance assessment; photolysis; quantitative analysis; reaction kinetics; two-dimensional modeling
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/190341
作者单位	Energy Technologies Area, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States; Department of Chemistry, University of California, Irvine, CA 92697-2025, United States; Department of Chemical Engineering and Materials Science, University of California, Irvine, CA 92697-2025, United States
推荐引用方式 GB/T 7714	Bala Chandran R.,Breen S.,Shao Y.,et al. Evaluating particle-suspension reactor designs for Z-scheme solar water splitting via transport and kinetic modeling[J],2018,11(1).
APA	Bala Chandran R.,Breen S.,Shao Y.,Ardo S.,&Weber A.Z..(2018).Evaluating particle-suspension reactor designs for Z-scheme solar water splitting via transport and kinetic modeling.Energy & Environmental Science,11(1).
MLA	Bala Chandran R.,et al."Evaluating particle-suspension reactor designs for Z-scheme solar water splitting via transport and kinetic modeling".Energy & Environmental Science 11.1(2018).