title: Preparation and Angle-Dependent Optical Properties of Brown Al/MnO2Composite Pigments in Visible and Infrared Region.
abstract: Traditional low infrared emissivity coatings based on aluminum flakes cannot own low IR emissivity and low lightness simultaneously. Herein, a new simple efficient method for the synthesis of brown Al/MnO2composite pigments with low IR emissivity and low lightness is reported, through forming MnO2layer on aluminum flakes by thermal cracking, then altering the shape and forming nanoshell by stirring in hot flowing liquid. The results indicate that the MnO2particles, which have tetragonal structure with high crystallinity, are needlelike and forming a complete shell on the aluminum flakes. The optical properties of composite pigments can be tuned by mass of KMnO4added in precursor and time of hot flowing. Strong angle-dependent optical effects are observed in five different angles through multi-angle reflectance spectrum, while low lightness and low IR emissivity are preserved. This work is expected to provide a new route for the preparation of colored aluminum effect pigments in low infrared emissivity coatings.
authors.affiliation: National Engineering Research Center of Electromagnetic Radiation Control Materials, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China. leng0771@gmail.com.|State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China. leng0771@gmail.com.
authors.forename: Yunfeng
authors.identifier: http://orcid.org/0000-0001-9929-1239
authors.initials: Y
authors.lastname: Liu
authors.affiliation: National Engineering Research Center of Electromagnetic Radiation Control Materials, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China.|State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China.
authors.forename: Jianliang
authors.initials: J
authors.lastname: Xie
authors.affiliation: National Engineering Research Center of Electromagnetic Radiation Control Materials, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China.|State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China.
authors.forename: Mei
authors.initials: M
authors.lastname: Luo
authors.affiliation: National Engineering Research Center of Electromagnetic Radiation Control Materials, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China.|State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China.
authors.forename: Bo
authors.initials: B
authors.lastname: Peng
authors.affiliation: National Engineering Research Center of Electromagnetic Radiation Control Materials, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China.|State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China.
authors.forename: Longjiang
authors.initials: L
authors.lastname: Deng
keywords: Aluminum flake; Angle-dependent pigments; Infrared emissivity; Lightness; Manganese dioxide; Reflectance