Highly concentrated synthesis of copper-zinc-tin-sulfide nanocrystals with easily decomposable capping molecules for printed photovoltaic applications.
Among various candidate materials, Cu2ZnSnS4 (CZTS) is a promising earth-abundant semiconductor for low-cost thin film solar cells. We report a facile, less toxic, highly concentrated synthetic method utilizing the heretofore unrecognized, easily decomposable capping ligand of triphenylphosphate, where phase-pure, single-crystalline, and well-dispersed colloidal CZTS nanocrystals were obtained. The favorable influence of the easily decomposable capping ligand on the microstructural evolution of device-quality CZTS absorber layers was clarified based on a comparative study with commonly used oleylamine-capped CZTS nanoparticles. The resulting CZTS nanoparticles enabled us to produce a dense and crack-free absorbing layer through annealing under a N2 + H2S (4%) atmosphere, demonstrating a solar cell with an efficiency of 3.6% under AM 1.5 illumination.
Department of Materials Science and Engineering, Yonsei University, 50 Yonsei-ro Seodaemun-gu, Seoul 120-749, Korea. jmoon@yonsei.ac.kr.
Youngwoo
Y
Kim
Kyoohee
K
Woo
Inhyuk
I
Kim
Yong Soo
YS
Cho
Sunho
S
Jeong
Jooho
J
Moon
D000588:Amines / Q000737:chemistry; D003300:Copper / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D010755:Organophosphates / Q000737:chemistry; D012666:Semiconductors; D012993:Solar Energy; D013440:Sulfides / Q000737:chemistry*; D014001:Tin / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry*
D000588:Amines; C571853:Cu2ZnSnS4; D010755:Organophosphates; D013440:Sulfides; C074782:phenylphosphate; D014001:Tin; D003300:Copper; D015032:Zinc; C008703:oleylamine