Abstract This manuscript reports on compared color evolution about phase transformation of α-FeOOH@SiO₂ and β-FeOOH@SiO2 pigments. Prepared α-FeOOH and β-FeOOH were coated with silica for enhancing thermal properties and coloration of both samples. To study phase and color of α-FeOOH and β-FeOOH, we prepared nano sized iron oxide hydroxide pigments which were coated with SiO2 using tetraethylorthosilicate and cetyltrimethyl-ammonium bro- mide as a surface modifier. The silica-coated both samples were calcined at high temperatures (300, 700 and 1000°C) and characterized by scanning electron microscopy, CIE L*a*b* color parameter measurements, transmission electron microscopy and UV-vis spectroscopy. The yellow α-FeOOH and β-FeOOH was transformed to α-Fe2O3 with red, brown at 300, 700°C, respectively.

• 유리(한국세라믹기술원, 엔지니어링 세라믹 센터) | Ri Yu
• 최균(한국세라믹기술원, 엔지니어링 세라믹 센터) | Kyoon Choi
• 피재환(한국세라믹기술원, 엔지니어링 세라믹 센터) | Jae-Hwan Pee
• 김유진(한국세라믹기술원, 엔지니어링 세라믹 센터) | YooJin Kim Corresponding Author