An organic donor/acceptor lateral superlattice at the nanoscale.
A precise control of the nanometer-scale morphology in systems containing mixtures of donor/acceptor molecules is a key factor to improve the efficiency of organic photovoltaic devices. Here we report on a scanning tunneling microscopy study of the first stages of growth of 2-[9-(1,3-dithiol-2-ylidene)anthracen-10(9H)-ylidene]-1,3-dithiole, as electron donor, and phenyl-C61-butyric acid methyl ester, as electron acceptor, on a Au(111) substrate under ultrahigh vacuum conditions. Due to differences in bonding strength with the substrate and different interactions with the Au(111) herringbone surface reconstruction, mixed thin films spontaneously segregate into a lateral superlattice of interdigitated nanoscale stripes with a characteristic width of about 10-20 nm, a morphology that has been predicted to optimize the efficiency of organic solar cells.
Otero
Roberto
R
Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, 28049 Madrid, Spain.
Ecija
David
D
Fernandez
Gustavo
G
Gallego
José María
JM
Sanchez
Luis
L
Martín
Nazario
N
Miranda
Rodolfo
R
D003460:Crystallization / Q000379:methods*; D004563:Electrochemistry / Q000379:methods*; D004579:Electron Transport; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods*; D009930:Organic Chemicals / Q000737:chemistry*; D010316:Particle Size; D010777:Photochemistry / Q000379:methods*; D012666:Semiconductors; D013499:Surface Properties
D046911:Macromolecular Substances; D009930:Organic Chemicals