title: Highly efficient copper-zinc-tin-selenide (CZTSe) solar cells by electrodeposition.
abstract: Highly efficient copper-zinc-tin-selenide (Cu2ZnSnSe4 ; CZTSe) thin-film solar cells are prepared via the electrodepostion technique. A metallic alloy precursor (CZT) film with a Cu-poor, Zn-rich composition is directly deposited from a single aqueous bath under a constant current, and the precursor film is converted to CZTSe by annealing under a Se atmosphere at temperatures ranging from 400 °C to 600 °C. The crystallization of CZTSe starts at 400 °C and is completed at 500 °C, while crystal growth continues at higher temperatures. Owing to compromises between enhanced crystallinity and poor physical properties, CZTSe thin films annealed at 550 °C exhibit the best and most-stable device performances, reaching up to 8.0 % active efficiency; among the highest efficiencies for CZTSe thin-film solar cells prepared by electrodeposition. Further analysis of the electronic properties and a comparison with another state-of-the-art device prepared from a hydrazine-based solution, suggests that the conversion efficiency can be further improved by optimizing parameters such as film thickness, antireflection coating, MoSe2 formation, and p-n junction properties.
authors.affiliation: Photo-electronic Hybrids Research Center, Korea Institute of Science and Technology (KIST), Seoul 136-791 (South Korea); Department of Nanomaterials Science and Engineering, University of Science and Technology, Daejeon 305-350 (South Korea).
authors.forename: Jong-Ok
authors.initials: JO
authors.lastname: Jeon
authors.forename: Kee Doo
authors.initials: KD
authors.lastname: Lee
authors.forename: Lee
authors.initials: L
authors.lastname: Seul Oh
authors.forename: Se-Won
authors.initials: SW
authors.lastname: Seo
authors.forename: Doh-Kwon
authors.initials: DK
authors.lastname: Lee
authors.forename: Honggon
authors.initials: H
authors.lastname: Kim
authors.forename: Jeung-hyun
authors.initials: JH
authors.lastname: Jeong
authors.forename: Min Jae
authors.initials: MJ
authors.lastname: Ko
authors.forename: BongSoo
authors.initials: B
authors.lastname: Kim
authors.forename: Hae Jung
authors.initials: HJ
authors.lastname: Son
authors.forename: Jin Young
authors.initials: JY
authors.lastname: Kim
mesh_terms: D003300:Copper / Q000737:chemistry*; D011211:Electric Power Supplies; D004595:Electroplating; D012643:Selenium / Q000737:chemistry*; D012993:Solar Energy; D014001:Tin / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry*
chemical_list: D014001:Tin; D003300:Copper; D012643:Selenium; D015032:Zinc
keywords: electrochemistry; electrodeposition; energy conversion; solar cells; thin films