Highly Solar Radiation Reflective Cr₂O₃–3TiO₂ Orange Nanopigment Prepared by a Polymer-Pyrolysis Method

Abstract

The present study reports the preparation and characterization of an orange nanopigment with high solar radiation reflective properties. Complex Cr2O3–3TiO2 nanoparticles were prepared by the pyrolysis of Cr–Ti precursors at high temperature, and the effects of the calcination temperature on the structure of Cr2O3–3TiO2 nanopigment were investigated by thermal analysis, X-ray diffraction, and transmission electron microscopy. The results reveal that the Cr2O–-3TiO2 pigments having rutile structure can be prepared by the calcination of the precursor at above 600 °C. All Cr2O3–3TiO2 pigments are granular in nature and present a homogeneous particle size of around 20 nm. The ultraviolet–visible near infrared (UV–vis-NIR) reflection spectra show that the Cr2O3–3TiO2 nanopigments have a reflection peak at around 600 nm, which reflects the orange color of these pigments. The average reflectance of Cr2O3–3TiO2 in the NIR range is around 53%, respectively, which is much higher than that of the visible light range. The prepared orange Cr2O3–3TiO2 nanopigments have a great potential in applications such as cool materials used for buildings with energy saving performance.

<strong>Acrylic acid in the synthesis of a trimetallic nano oxide </strong><strong>as NIR reflectance pigment <em>via</em> polymer pyrolysis method</strong>

“…With the existence of a large amount of H 2 O, Ti(C4H 9 O) 4 mainly hydrolyze with the water in situ and lead to an immediate nucleation of Ti(OH) 4 , which is distributed randomly within the polymer precursor, as shown in Figure 1 [4]. The Ni (II) and Mn (II) ions are bound by the strong ionic bonds between the polymeric chains.…”

“…The Ni (II) and Mn (II) ions are bound by the strong ionic bonds between the polymeric chains. Ti(OH) 4 is distributed randomly within the polymer precursor. This uniform inmobilization of metallic ions in the polymer chains favors the formation of NiTiO3 nanoparticles in the following pyrolysis process.…”

“…Large-scale application of metal oxides with nanometer size as cool colors with special optical properties have prompted the development of several widely used methods, including sol-gel coprecipitation, milling, hydrothermal method [1][2][3][4][5][6][7][8][9][10]. The above methods can produce highly crystalline and uniformly sized nanoparticles.…”

Preparation and characterization of “green” hybrid clay-dye nanopigments

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Thiophene‐Fused‐Heteroaromatic Diones as Promising NIR Reflectors for Radiative Cooling

“…Currently,the dominating reflectance pigments are inorganic materials such as titanium oxide, [15] chromium oxide, [16] and rare-earth oxide. Currently,the dominating reflectance pigments are inorganic materials such as titanium oxide, [15] chromium oxide, [16] and rare-earth oxide.…”