Sol–gel preparation of Ni/TiO2 catalysts with bimodal pore structures Original Research Article

Ni/TiO2 with bimodal pore structure was prepared from nickel nitrate and titanium alkoxide by a sol–gel process under acidic conditions in the presence of formamide. The Ni/TiO2 has continuous macropores which are formed by fixing the transitional structure of phase separation. Although the addition of nickel nitrate in the sol–gel reaction of titanium alkoxide steeply decreases the phase separation tendency, the macropore size can be controlled by changing the composition of preparation. The Ni/TiO2 prepared by sol–gel has higher dispersion of Ni compared with that prepared by impregnation, and shows catalytic activity for the selective hydrogenation of crotonaldehyde: selectivity in the hydrogenation of Cdouble bond; length as m-dashC bond is much higher than that of Cdouble bond; length as m-dashO bond over sol–gel-derived Ni/TiO2.