Synthesis and coloration of highly dispersive SiO₂/BiVO₄ hybrid pigments with low cost and high NIR reflectance

Abstract

Highly dispersed SiO2/BiVO4 hybrid pigments with a spherical structure and high near-infrared (NIR) reflectance have been successfully fabricated by a facile sol–gel method followed by calcination. The dispersed and uniformly spherical particles of the hybrid pigments were caused by the support provided by SiO2 microspheres, and their color was adjusted via the band-gap energy, which was changed with the incorporation of SiO2 microspheres. The SiO2/BiVO4-3 hybrid pigment presented higher yellow hues (b* = 91.42) and more dispersed spherical particles than other as-prepared hybrid pigments and commercially available BiVO4-based yellow pigment. This strategy could save 72 wt% resource of BiVO4 while yielding the same amount of yellow pigment with high color performance. Therefore, the prepared hybrid pigments not only dramatically decreased the cost of expensive pigments, but also saved scarce resources and reduced environmental pollution. In addition, the SiO2/BiVO4-3 hybrid pigment also presented high NIR reflective performance, which demonstrated that it would be a favorable candidate for colorful NIR reflective pigments with wide applications in heat insulation.

Preparation of Environmentally Friendly BiVO4@SiO2 Encapsulated Yellow Pigment with Remarkable Thermal and Chemical Stability

“…These obtained results indicate that the introduction of SiO 2 (37.5% in mass content) does not affect the chromatic properties of BiVO 4 pigment. A similar phenomenon was also found for the synthesis of hybrid SiO 2 /BiVO 4 pigments, with SiO 2 as the core, by He et al [33]. The addition of SiO 2 is expected to decrease the use cost of yellow pigment greatly since BiVO 4 is much more costly than SiO 2 .…”

Facile preparation of high conductive silver electrodes by dip-coating followed by quick sintering

“…Infrared sintering technology is a photonic sintering approach for metal nanoparticles [38][39][40]. In this work, the infrared sintering process is used to promote the deformation of PVP on the surface of AgNPs and improve the conductivity of the silver film.…”

Mechanochemical preparation of low cost kaolinite-based BiVO4 hybrid pigments with high near infrared reflectance

“…In recent years, it has been recognized as an effective way for blocking solar radiation energy to reduce indoor temperature by developing the smarter nontoxic near-infrared reflective (NIR) cool inorganic pigments [2][3][4]. It was confirmed that the temperature difference could reach 10 °C before and after coating NIR inorganic pigments with high solar reflection and thermal emissivity [5,6]. It is well-known that the spectrum of the solar rays also includes ultraviolet (UV) (5%) and visible light (43%) in addition to near-infrared waveband (52%) [7].…”

“…At present, some colored non-toxic NIR and infrared radiative pigments had presented great broad application prospects in the field of energy-saving architectural coatings [5,6]. As an environment-friendly yellow inorganic pigments, bismuth yellow (BiVO 4 ) has been identified as an ideal substitute for conventional industrial inorganic yellow pigments (e.g.…”