Nanoscale Co and Ni catalysts in silica were synthesized using sol-gel method for hydrogen production from steam reforming of methanol (SRM) in silicon microreactors with 50 mu m channels. Silica sol-gel support with porous structure gives specific surface area of 452.35 m(2) g(-1) for Ni/SiO2 and 337.72 m(2) g(-1) for CO/SiO2. TEM images show the particles size of Ni and Co catalysts to be < 10 nm. The EDX results indicate Co and Ni loadings of 5-6 wt.% in silica which is lower than the intended loading of 12 wt.%. The DTA and XRD data suggest that 450 degrees C is an optimum temperature for catalyst calcination when most of the metal hydroxides are converted to metal oxides without significant particle aggregation to form larger crystallites. SRM reactions show 53% methanol conversion with 74% hydrogen selectivity at 5 mu L min(-1) and 200 degrees C for Ni/SiO2 catalyst, which is higher than that for CO/SiO2. The activity of the metal catalysts decrease significantly after SRM reactions over 10 h, and it is consistent with the magnetization (VSM) results indicating that similar to 90% of Co and similar to 85% of Ni become non-ferromagnetic after 10 h. (c) 2006 Elsevier B.V. All rights reserved.