Hydrothermal synthesis and characterization of novel yellow pigments based on V5+ doped BiPO4 with high near-infrared reflectance. Issue 35 (29th May 2018)

• Record Type: Journal Article
• Authors: Ding, Cheng; Han, Aijun; Ye, Mingquan; Zhang, Yu; Yao, Lingyun; Yang, Jiling
• Is Part Of: RSC advances. Volume 8:Issue 35(2018)
• Page Start: 19690
• Page End: 19700
• Publication Date: 2018-05-29
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c8ra02406e
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : A series of new yellow pigments was synthesized (BiP1− x V x O4 ), coatings colored with synthesized pigments have high NIR solar reflectance. Abstract : In this study, a series of novel pigments based on V 5+ doped BiPO4 have been prepared for the first time via a facile hydrothermal method and characterized using several analytical techniques, such as X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), ultraviolet-visible-near-infrared (UV-vis-NIR) spectrometry, the Commission International de l'Eclairage (CIE) L * a * b * color scales and thermogravimetry and differential thermal analysis (TG-DTA). The investigation demonstrated that the synthesized pigments of BiP1− x V x O4 ( x = 0.00, 0.01, 0.05, 0.08, 0.10, 0.15) had a monazite-type phase structure and were about 0.25–2 μm in size. Meanwhile, the substitution of V 5+ for P 5+ in BiPO4 resulted in the band gap of the pigments varying from 3.657 to 3.244 eV and its mechanism was explained by charge-transfer and energy band theory, while the color changed from white to yellow. More importantly, the V 5+ doped pigments possessed high NIR reflectance (>72%) and NIR solar reflectance (≥75.64%) in the range 700–2500 nm. Moreover, coatings colored with synthetic pigments have higher NIR solar reflectance (≥78.59%) than conventional pigments. Additionally, the pigments showed good thermal/chemical stabilities in high-temperature/acid/alkaline tests. In conclusion, the pigments have the potential to be applied as "cool pigments" to reduce energy consumption.