A stabilizer-free method based on segmented flow for the continuous
synthesis of TiO2 supported noble metal nanoparticles (M/TiO2-MR, M =
Pd, Pt or Au) was proposed. Due to the enhanced mixing performance
arising from the internal convection in the discrete plugs, the particle
size of noble metal nanoparticles could be well controlled by reducing
the metal precursors with NaBH4 just in the presence of TiO2 without
using any stabilizer. In comparison with the batch method, the
as-prepared M/TiO2-MR had smaller noble metal particle size and better
dispersity. Experimental results showed that adjusting the oil-to-water
phase ratio or increasing the total volume flow rate and synthetic
temperature could lead to smaller average particle size with narrower
distribution. The as-prepared M/TiO2-MR possessed higher catalytic
activities in the hydrolysis of ammonia borane than those prepared by
the batch method, which could be ascribed to smaller noble metal
nanoparticles, exposing more active sites.
Continuous synthesis of TiO2-supported noble metal NPs and their application in ammonia borane hydrolysis
