Precipitation of Ni and NiO nanoparticle catalysts on zeolite and mesoporous silica by rotary chemical vapor deposition

Ni and NiO catalytic nanoparticles were precipitated onto mesoporous silica and zeolite by rotary chemical vapor deposition (RCVD) using NiCp2 as a precursor. The diameter of the nanoparticles precipitated onto zeolite increased from 5 to 50 nm when the oxygen flow rate (R-O2) increased from 0 to 0.33 x 10(-6) m(3) s(-1), whereas that of the nanoparticles precipitated onto mesoporous silica was 5 nm, independent of R-O2. The nanoparticles could be precipitated inside of the mesoporous silica pores but outside the zeolite pores. The highest H-2 production rate in the methanol-steam reforming reaction was 1150 x 10(-3) mol kg(-1) s(-1) at 633 K, which was achieved with a Ni/NiO catalyst on mesoporous silica, and this H-2 production rate is almost six times greater than that of the best Ni catalysts reported in literature. (C) 2013 The Ceramic Society of Japan. All rights reserved.