新能源材料手技术Renewable Energy: Materials and TechnologiesL3: Solar Energy and Conversion Technologies (II)- Dye Sensitized Solar Cells (DSSC) (2, 3)Dr Yimin Chaoy.chao@uea.ac.ukwww.uea.ac.uk/chemistry/people/faculty/chao
新能源材料与技术 Renewable Energy: Materials and Technologies L3: Solar Energy and Conversion Technologies (II) - Dye Sensitized Solar Cells (DSSC) (2, 3) Dr Yimin Chao y.chao@uea.ac.uk www.uea.ac.uk/chemistry/people/faculty/chao
SynopsisLecture1ABluffer'sGuidetoPhotophysics andPhotochemistryLecture2Whymakedye-sensitized(andotherexcitonic)solarcells?“Classic"Dye-SensitizedSolarCells(DSSCs)Lecture3Recentdevelopments-p-TypeDSSCs,perovskiteDsSCs,OPVsCommercialization
Synopsis Lecture 1 A Bluffer’s Guide to Photophysics and Photochemistry Lecture 2 Why make dye-sensitized (and other excitonic) solar cells? “Classic” Dye-Sensitized Solar Cells (DSSCs) Lecture 3 Recent developments – p-Type DSSCs, perovskite DSSCs, OPVs Commercialization 46
Semiconductorsolarcellscanbeupto44%efficientDye-sensitizedsolarcellsareonly10to15%efficientWhyConsiderDSSCs?
Why Consider DSSCs? Semiconductor solar cells can be up to 44% efficient Dye-sensitized solar cells are only 10 to 15% efficient 47
Cost-Si currently $0.50 to$1per watt.Predicted$0.36perwatt(2017)DSSC-mayhit$0.30perwatt.Lowlightperformance-Si,GaAsetcworkbestwithsolarconcentratorsDssCs stillworkoncloudydays(andindoors)Transparency-DssCs can be incorporated into coloured windowsAlso-lightweight,canbeflexible,betterhightemperatureperformance
Cost – Si currently $0.50 to $1 per watt. Predicted $0.36 per watt (2017) DSSC – may hit $0.30 per watt. Low light performance – Si, GaAs etc work best with solar concentrators DSSCs still work on cloudy days (and indoors) Transparency – DSSCs can be incorporated into coloured windows Also – lightweight, can be flexible, better high temperature performance 48
What isDyeSensitization?Electron injection,efficiencyPinjConductionband4E=2.5eV4E=3.2eVSensitizerValenceband3.2eVis390nm,2.5evis495nmWideband gap semiconductor(e.g. TiO2, SnO2)Excited stateof adye absorbingvisible lighttransfers electrons toawidebandgap(UVabsorbing)semiconductorFirst use-Vogel, 1870s, photography. Understanding developed from1960sonwards
What is Dye Sensitization? Conduction band Valence band ΔE = 3.2 eV Wide band gap semiconductor (e.g. TiO2, SnO2) ΔE = 2.5 eV 3.2 eV is 390 nm, 2.5 eV is 495 nm Sensitizer Excited state of a dye absorbing visible light transfers electrons to a wide band gap (UV absorbing) semiconductor First use – Vogel, 1870s, photography. Understanding developed from 1960s onwards. Electron injection, efficiency Φinj 49