title: Air-stable near-infrared AgInSe₂ nanocrystals.
abstract: We present the synthesis of air-stable AgInSe2 nanocrystals via thermolysis of an Ag-In-thiolate complex followed by an anion exchange reaction. Evolution of the Ag:In:Se ratio with the reaction time demonstrates progressive incorporation of In(3+) in β-Ag2Se seeds. While their lattice stays in the metastable orthorhombic crystal structure, the final AgInSe2 nanocrystal shape can be spherical, pyramidal, or prismatic depending on reaction conditions. These nanocrystals emit from trap states between 800 and 1300 nm, which is a biologically and technologically important near-infrared range, with a photoluminescence quantum yield up to an order of magnitude of 21%. The appearance of a shoulder within the photoluminescence spectra between 845 and 890 nm is correlated to the presence of prismatic nanocrystals.
authors.affiliation: Centre d'Optique, Photonique et Laser (COPL), Département de Physique, de Génie Physique et d'Optique, Université Laval , 2375 Rue de la Terrasse, Québec, QC, Canada G1V 0A6.
authors.forename: Marc-Antoine
authors.initials: MA
authors.lastname: Langevin
authors.forename: Anna M
authors.initials: AM
authors.lastname: Ritcey
authors.forename: Claudine Nì
authors.initials: CN
authors.lastname: Allen
mesh_terms: D000388:Air; D004355:Drug Stability; D007204:Indium / Q000737:chemistry*; D007259:Infrared Rays; D053758:Nanoparticles / Q000737:chemistry*; D055620:Optical Phenomena; D010316:Particle Size; D018036:Selenium Compounds / Q000737:chemistry*; D018030:Silver Compounds / Q000737:chemistry*
chemical_list: D018036:Selenium Compounds; D018030:Silver Compounds; D007204:Indium