--- res: bibo_abstract: - Lead halide perovskite materials have attracted significant attention in the context of photovoltaics and other optoelectronic applications, and recently, research efforts have been directed to nanostructured lead halide perovskites. Collodial nanocrystals (NCs) of cesium lead halides (CsPbX3, X = Cl, Br, I) exhibit bright photoluminescence, with emission tunable over the entire visible spectral region. However, previous studies on CsPbX3 NCs did not address key aspects of their chemistry and photophysics such as surface chemistry and quantitative light absorption. Here, we elaborate on the synthesis of CsPbBr3 NCs and their surface chemistry. In addition, the intrinsic absorption coefficient was determined experimentally by combining elemental analysis with accurate optical absorption measurements. 1H solution nuclear magnetic resonance spectroscopy was used to characterize sample purity, elucidate the surface chemistry, and evaluate the influence of purification methods on the surface composition. We find that ligand binding to the NC surface is highly dynamic, and therefore, ligands are easily lost during the isolation and purification procedures. However, when a small amount of both oleic acid and oleylamine is added, the NCs can be purified, maintaining optical, colloidal, and material integrity. In addition, we find that a high amine content in the ligand shell increases the quantum yield due to the improved binding of the carboxylic acid.@eng bibo_authorlist: - foaf_Person: foaf_givenName: Jonathan foaf_name: De Roo, Jonathan foaf_surname: De Roo - foaf_Person: foaf_givenName: Maria foaf_name: Ibáñez, Maria foaf_surname: Ibáñez foaf_workInfoHomepage: http://www.librecat.org/personId=43C61214-F248-11E8-B48F-1D18A9856A87 orcid: 0000-0001-5013-2843 - foaf_Person: foaf_givenName: Pieter foaf_name: Geiregat, Pieter foaf_surname: Geiregat - foaf_Person: foaf_givenName: Georgian foaf_name: Nedelcu, Georgian foaf_surname: Nedelcu - foaf_Person: foaf_givenName: Willem foaf_name: Walravens, Willem foaf_surname: Walravens - foaf_Person: foaf_givenName: Jorick foaf_name: Maes, Jorick foaf_surname: Maes - foaf_Person: foaf_givenName: Jose foaf_name: Martins, Jose foaf_surname: Martins - foaf_Person: foaf_givenName: Isabel foaf_name: Van Driessche, Isabel foaf_surname: Van Driessche - foaf_Person: foaf_givenName: Maksym foaf_name: Kovalenko, Maksym foaf_surname: Kovalenko - foaf_Person: foaf_givenName: Zeger foaf_name: Hens, Zeger foaf_surname: Hens bibo_doi: 10.1021/acsnano.5b06295 bibo_issue: '2' bibo_volume: 10 dct_date: 2016^xs_gYear dct_language: eng dct_publisher: American Chemical Society@ dct_title: Highly dynamic ligand binding and light absorption coefficient of cesium lead bromide perovskite nanocrystals@ ...