Ball-Milling Assisted Pyrolysis Fabrication of VO <sub>2</sub>(M) Nanoparticles with Exemplary Optical Performance for Smart Windows

Abstract In this work, two silicon nanostructures were doped into polymer/nematic liquid crystal composites to regulate the electric-optical performance. Commercial SiO2 nanoparticles and synthesized thiol polyhedral oligomeric silsesquioxane (POSS-SH) were chosen as the dopants to afford the silicon nanostructures. SiO2 nanoparticles were physically dispersed in the composites and the nanostructure from POSS-SH was implanted into the polymer matrix of the composites via photoinduced thiol-ene crosslinking. SEM results indicated that the implantation of POSS microstructure into the polymer matrix was conducive to obtaining the uniform porous polymer microstructures in the composites while the introduction of SiO2 nanoparticles led to the loose and heterogeneous polymer morphologies. The electric-optical performance test results also demonstrated that the electric-optical performance regulation effect of POSS microstructure was more obvious than that of SiO2 nanoparticles. The driving voltage was reduced by almost 80% if the concentration of POSS-SH in the composite was nearly 8 wt% and the sample could be completely driven by the electric field whose voltage was lower than the safe voltage for continuous contact (24 V). This work could provide a creative approach for the regulation of electric-optical performance for polymer/nematic liquid crystal composites and the fabrication of low voltage-driven PDLC films for smart windows.

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Bio-inspired TiO2 nano-cone antireflection layer for the optical performance improvement of VO2 thermochromic smart windows

Scientific Reports ◽

10.1038/s41598-020-68411-6 ◽

2020 ◽

Vol 10 (1) ◽

Cited By ~ 1

Author(s):

Sai Liu ◽

Chi Yan Tso ◽

Hau Him Lee ◽

Yi Zhang ◽

Kin Man Yu ◽

...

Keyword(s):

Performance Improvement ◽

Optical Performance ◽

Smart Windows

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One-step ball milling synthesis of VO2 (M) nanoparticles with exemplary thermochromic performance

SN Applied Sciences ◽

10.1007/s42452-021-04154-x ◽

2021 ◽

Vol 3 (4) ◽

Author(s):

Chiyuan Wang ◽

Huiyan Xu ◽

Tongyao Liu ◽

Shuaijun Yang ◽

Yong Nie ◽

...

Keyword(s):

Phase Transition ◽

Transition Temperature ◽

Ball Milling ◽

Phase Transition Temperature ◽

Large Scale ◽

Molar Ratio ◽

Ambient Conditions ◽

Doping Amount ◽

Smart Windows ◽

Milling Method

AbstractVanadium dioxide (VO2) has demonstrated highly potential for smart windows because of its thermochromic property. This study represents the development of a facile but efficient method for the synthesis of VO2 (M) nanoparticles by ball milling method under ambient conditions, without release of waste liquid or gases. The key variables related to synthesis, including milling time and molar ratio of raw materials, have been investigated. It was found that the pure-phase VO2 (M) nanoparticles with the sizes of the particles ranged from 20 to 50 nm and relatively good dispersivity could be prepared by optimizing process parameters. For practice use to decrease the phase transition temperature, elemental W doping amount of 2 at.%, V1−xWxO2 (M) nanoparticles were also studied, and their glass coating exhibits high thermochromic performance with luminous transmittance (Tlum) of 44.18%, solar regulation efficiency (∆Tsol) of 9.64%, and the critical phase transition temperature (Tc) of ~ 42 °C. This work demonstrates a green and promising ball milling method to fabricate large scale VO2 (M) and V1−xWxO2 (M) nanoparticles for smart windows.

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Preparation of VxW1−xO2(M)@SiO2 ultrathin nanostructures with high optical performance and optimization for smart windows by etching

Journal of Materials Chemistry A ◽

10.1039/c3ta12232h ◽

2013 ◽

Vol 1 (40) ◽

pp. 12545 ◽

Cited By ~ 30

Author(s):

Aibin Huang ◽

Yijie Zhou ◽

Yamei Li ◽

Shidong Ji ◽

Hongjie Luo ◽

...

Keyword(s):

Optical Performance ◽

Smart Windows

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Enhanced optical performance of thermochromic VO2 based on multilayer designs

The European Physical Journal Applied Physics ◽

10.1051/epjap/2020190339 ◽

2019 ◽

Vol 88 (3) ◽

pp. 30301

Author(s):

Houao Liu ◽

Hao Song ◽

Hao Xie ◽

Guanchao Yin

Keyword(s):

Solar Spectrum ◽

Multilayer Structures ◽

Optical Performance ◽

Smart Windows ◽

Optical Responses ◽

Relative Enhancement ◽

Thermochromic Material ◽

Glass Interface ◽

Base Structure

VO2 is a widely studied thermochromic material for smart windows. In this work, we comprehensively studied optical responses of VO2-based multilayer structures. It is discovered that one-layer antireflection layer is capable of effectively enhancing both luminous transmittance (Tlum) and solar transmittance (Tsol), solar spectrum modulation (ΔTsol) is however quite moderate. Employing a two-top-layer strategy further improves the optical performance of VO2, especially with an increase of ΔTsol from 0.068 to 0.082. Remarkably, combining a layer with an index of 2.2 at the VO2/glass interface continues to enhance the optical performance, leading to the highest Tlum and ΔTsol among the investigated multilayer structures. Compared to the base structure of VO2/glass, it contributes to a relative enhancement of 26.4% (from 0.435 to 0.550) for Tlum (<τc), 35.3% (from 0.362 to 0.490) for Tlum (>τc), and 71.7% (from 0.060 to 0.103) for ΔTsol.

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