title: A Dual-Responsive Nanocomposite toward Climate-Adaptable Solar Modulation for Energy-Saving Smart Windows.
abstract: In this work, a novel fully autonomous photothermotropic material made by hybridization of the poly(N-isopropylacrylamide) (PNIPAM) hydrogel and antimony-tin oxide (ATO) is presented. In this photothermotropic system, the near-infrared (NIR)-absorbing ATO acts as nanoheater to induce the optical switching of the hydrogel. Such a new passive smart window is characterized by excellent NIR shielding, a photothermally activated switching mechanism, enhanced response speed, and solar modulation ability. Systems with 0, 5, 10, and 15 atom % Sb-doped ATO in PNIPAM were investigated, and it was found that a PNIPAM/ATO nanocomposite is able to be photothermally activated. The 10 atom % Sb-doped PNIPAM/ATO exhibits the best response speed and solar modulation ability. Different film thicknesses and ATO contents will affect the response rate and solar modulation ability. Structural stability tests at 15 cycles under continuous exposure to solar irradiation at 1 sun intensity demonstrated the performance stability of such a photothermotropic system. We conclude that such a novel photothermotropic hybrid can be used as a new generation of autonomous passive smart windows for climate-adaptable solar modulation.
authors.affiliation: School of Materials Science and Engineering, Nanyang Technological University , 50 Nanyang Avenue, 639798 Singapore, Singapore.
authors.forename: Heng Yeong
authors.identifier: http://orcid.org/0000-0002-6380-9363
authors.initials: HY
authors.lastname: Lee
authors.affiliation: School of Materials Science and Engineering, Nanyang Technological University , 50 Nanyang Avenue, 639798 Singapore, Singapore.|Environmental Chemistry and Materials Centre, Nanyang Environment & Water Research Institute , 1 Cleantech Loop, 637141 Singapore, Singapore.
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Cai
authors.affiliation: School of Materials Science and Engineering, Nanyang Technological University , 50 Nanyang Avenue, 639798 Singapore, Singapore.
authors.forename: Shuguang
authors.initials: S
authors.lastname: Bi
authors.affiliation: Environmental Chemistry and Materials Centre, Nanyang Environment & Water Research Institute , 1 Cleantech Loop, 637141 Singapore, Singapore.
authors.forename: Yen Nan
authors.initials: YN
authors.lastname: Liang
authors.affiliation: School of Materials Science and Engineering, Nanyang Technological University , 50 Nanyang Avenue, 639798 Singapore, Singapore.
authors.forename: Yujie
authors.initials: Y
authors.lastname: Song
authors.affiliation: School of Materials Science and Engineering, Nanyang Technological University , 50 Nanyang Avenue, 639798 Singapore, Singapore.|Environmental Chemistry and Materials Centre, Nanyang Environment & Water Research Institute , 1 Cleantech Loop, 637141 Singapore, Singapore.
authors.forename: Xiao Matthew
authors.initials: XM
authors.lastname: Hu
keywords: nanocomposite polymer gel; nanoheaters; smart windows; thermotropic materials; transparent conducting oxide