title: Near infrared absorption of CdSe(x)Te(1-x) alloyed quantum dot sensitized solar cells with more than 6% efficiency and high stability.
abstract: CdSe0.45Te0.55 alloyed quantum dots (QDs) with excitonic absorption onset at 800 nm and particle size of 5.2 nm were prepared via a noninjection high-temperature pyrolysis route and used as a sensitizer in solar cells. A postsynthesis assembly approach with use of bifunctional linker molecule mercaptopropionic acid (MPA) capped water-soluble QDs, obtained via ex situ ligand exchange from the initial oil-dispersible QDs, was adopted for tethering QDs onto mesoporous TiO2 film. With the combination of high loading of the QD sensitizer and intrinsic superior optoelectronic properties (wide absorption range, high conduction band edge, high chemical stability, etc., relative to their constituents CdSe and CdTe) of the adopted CdSe0.45Te0.55 QD sensitizer, the resulting CdSexTe1-x alloyed QD-based solar cells exhibit a record conversion efficiency of 6.36% (Jsc = 19.35 mA/cm(2), Voc = 0.571 V, FF = 0.575) under full 1 sun illumination, which is remarkably better than that of the reference CdSe and CdTe QD based ones. Furthermore, the solar cells with Cu2S counter electrodes based on eletrodeposition of Cu on conductive glass show long-term (more than 500 h) stability.
authors.affiliation: State Key Laboratory of Bioreactor Engineering, Institute of Applied Chemistry, East China University of Science and Technology, Shanghai 200237, China.
authors.forename: Zhenxiao
authors.initials: Z
authors.lastname: Pan
authors.forename: Ke
authors.initials: K
authors.lastname: Zhao
authors.forename: Jin
authors.initials: J
authors.lastname: Wang
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
authors.forename: Yaoyu
authors.initials: Y
authors.lastname: Feng
authors.forename: Xinhua
authors.initials: X
authors.lastname: Zhong
mesh_terms: D000042:Absorption; D000497:Alloys / Q000737:chemistry*; D019187:Cadmium Compounds / Q000737:chemistry*; D011211:Electric Power Supplies; D004566:Electrodes; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry*; D012993:Solar Energy; D013691:Tellurium / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry
chemical_list: D000497:Alloys; D019187:Cadmium Compounds; D018036:Selenium Compounds; C009495:titanium dioxide; C058667:cadmium selenide; D014025:Titanium; D013691:Tellurium