화학공학소재연구정보센터
Journal of Materials Science, Vol.35, No.1, 115-121, 2000
Characterization of aluminosilicate on rutile surface by high resolution solid state NMR
Pigments of titanium dioxide rutile, coated with SiO2-Al2O(3), have been characterized by high-resolution solid state NMR. The model samples were prepared following four synthesis routes differing by the aluminate and silicate salts addition sequence. From Al-27 single pulse MAS and 3Q-MAS NMR experiments, we characterize short range order around Al and distinguish several types of environment: Al-IV, Al-V, Al-VI and Al-VI linked to Ti, depending upon synthesis route and thermal treatment. The major difference between the different samples is observed after heat treatment at 750 degrees C. Rotational echo double resonance Al-27-H-1 and cross-polarization H-Si experiments provide longer range distance information through dipolar coupling to proton. Two types of surface treatment can be distinguished from Al-27-H-1 Redor by the presence of proton free alumina domain in the surface treatment.