Deconvoluting contributions of photoexcited species in polymer-quantum dot hybrid photovoltaic materials

作者：Couderc Elsa; Greaney Matthew J; Thornbury William; Brutchey Richard L^*; Bradforth Stephen E

来源：Journal of Photonics for Energy, 2015, 5(1): 057404.

DOI：10.1117/1.JPE.5.057404

• bulk heterojunction
• hybrid solar cell
• charge transfer
• ultrafast spectroscopy
• chemical doping

Ultrafast transient absorption spectroscopy is used in conjunction with spectroelectrochemistry and chemical doping experiments to study the photogeneration of charges in hybrid bulk heterojunction (BHJ) thin films composed of poly[2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b:3,4-b']-dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT) and CdSe nanocrystals. Chemical doping experiments on hybrid and neat PCPDTBT: CdSe thin films are used to deconvolute the spectral signatures of the transient states in the near infrared. We confirm the formation and assignment of oxidized species in chemical doping experiments by comparing the spectral data to that from spectroelectrochemical measurements on hybrid and neat PCPDTBT: CdSe BHJ thin films. The deconvolution procedure allows extraction of the polaron populations in the neat polymer and hybrid thin films.

• 出版日期2015-1-2