title: High-throughput measurements of thermochromic behavior in V(1-x)Nb(x)O(2) combinatorial thin film libraries.
abstract: We describe a high-throughput characterization of near-infrared thermochromism in V1-xNbxO2 combinatorial thin film libraries. The oxide thin film library was prepared with a VO2 crystal structure and a continuous gradient in composition with Nb concentrations in the range of less than 1% to 45%. The thermochromic phase transition from monoclinic to tetragonal was characterized by the accompanying change in near-infrared reflectance. With increasing Nb substitution, the transition temperature was depressed from 65 to 35 °C, as desirable for smart window applications. However, the magnitude of the reflectance change across the thermochromic transition was also reduced with increasing Nb film content. Data collection, handling, and analysis supporting thermochromic characterization were fully automated to achieve high throughput. Using this system, in 14 h, temperature-dependent infrared reflectances were measured at 165 arbitrary locations on a thin film combinatorial library; these measurements were analyzed for thermochromic transitions in minutes.
authors.affiliation: Material Measurement Laboratory, National Institute of Standards and Technology , 100 Bureau Drive, MS 8520, Gaithersburg, Maryland 20899-8520, United States.
authors.forename: S C
authors.initials: SC
authors.lastname: Barron
authors.forename: J M
authors.initials: JM
authors.lastname: Gorham
authors.forename: M P
authors.initials: MP
authors.lastname: Patel
authors.forename: M L
authors.initials: ML
authors.lastname: Green
mesh_terms: D020650:Combinatorial Chemistry Techniques / Q000379:methods*; D057166:High-Throughput Screening Assays; D007202:Indicators and Reagents; D009556:Niobium / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D054852:Small Molecule Libraries; D013816:Thermodynamics; D017968:Vanadium Compounds / Q000737:chemistry*
chemical_list: D007202:Indicators and Reagents; D010087:Oxides; D054852:Small Molecule Libraries; D017968:Vanadium Compounds; C581824:vanadium dioxide; D009556:Niobium
keywords: combinatorial thin film library; high-throughput screening; metal−insulator transition; near-infrared reflectance; thermochromics; vanadium dioxide (VO2)