Main content area

VO₂@SiO₂/Poly(N-isopropylacrylamide) Hybrid Nanothermochromic Microgels for Smart Window

Wang, Yu, Fang Zhao,, Wang, Jie, Khan, Ali Raza, Shi, Yulin, Chen, Zhang, Zhang, Kaiqiang, Li, Li, Gao, Yanfeng, Guo, Xuhong
Industrial & engineering chemistry process design and development 2018 v.57 no.38 pp. 12801-12808
hydrogels, microgels, nanoparticles, oxidation, polymerization, process design, silica, thermochromatic materials, transmittance
VO₂/PNIPAm hybrid thermochromic material has been verified as promising to improve optical performance of smart windows. However, VO₂ can be easily oxidized especially when being dispersed in the hydrogel matrix, and also the nonuniform dispersion of VO₂ in a host will worsen the material’s optical performance. Herein, pure VO₂(M)@SiO₂ nanoparticles (NPs) were first prepared using a surfactant-free method. Then VO₂(M)@SiO₂/PNIPAm hybrid microgels were synthesized through suspension polymerization. The VO₂(M)@SiO₂ NPs in the hydrogel matrix exhibited obviously improved resistance to oxidation. Monodispersed hybrid microgel with uniformly distributed VO₂(M)@SiO₂ NPs (Sample I) was obtained. Meanwhile, compared with the best VO₂ film reported, our composite microgel (Sample III) demonstrated a 164% increase in the solar modulating ability at a relatively high average luminous transmittance (38.4%). All these remarkable features of VO₂(M)@SiO₂/PNIPAm microgel synthesized in our work will help a lot in the practical application of the inorganic–organic hybrid nanothermochromic materials.