Fabrication and optical performance of W-VO2/PVP/AAO composite structure in visual and near infrared band

Vanadium dioxide with tungsten doping (W-VO 2 ), Polyvinylpyrrolidone (PVP) and anodic alumium oxide (AAO) composite structure (W-VO 2 /PVP/AAO) was fabricated by introducing the W-VO 2 /PVP solution into pores of AAO by capillary force. The morphology and optical performance were studied. W-VO 2 /PVP can form compact distribution in pores of AAO by increasing the stickiness, and then enhance the visible light transmittance and solar modulation ability simultaneous. We optimized the thickness of W-VO 2 /PVP/AAO with continuous distribution in pore, and the visible light transmittance and solar modulation ability can reach up to 64.7% and 19.2%, respectively. This result will benefit to the application of VO 2 nanoparticles in smart windows. Vanadium dioxide (VO 2 ) is a thermochromic material and has great application potential in smart windows for energy conversion. It has been the focus of research on improving the visible light transmittance ( T lum ) and solar modulation ability (Δ T sol ) while reducing the phase transition temperature ( T c ) of VO 2 . To achieve this goal, we designed and constructed a composite structure by W-VO 2 NPs with a T c of 34 ℃ and PVP in AAO, as shown in Fig. c. We studied the effect of W-VO 2 concentration, stickiness and thickness of film on the thermochromic performance of composite films and optimized these parameters according to the performance of T lum and Δ T sol . We found that the T lum can reach up to 64.7% and the Δ T sol reach up to 19.2% with continuous distribution in pore. This work provides a new idea for enhancing the thermochromic performance and promoting the development of VO 2 thermochromic smart windows.