The precursor for a lithium-ion sieve is prepared using an inorganic precipitation-peptization method with titanium sulfate as the titanium source and lithium acetate as the lithium source. The effects of Ni2+ (Nickel ions) doping on the stability of the sol, crystal morphology and interplanar spacing of Li2TiO3 are investigated. The results indicate that, after Ni2+ doping with varying fractions, the stability of the precursor sol first increases then decreases, and the maximum stabilization time of the precursor sol doped with 1% Ni2+ is 87 h. When doped with 1% Ni2+, the sol performance is most stable, the porous Li2TiO3 is obtained, and the specific surface area of Li2TiO3 increases by up to 1.349 m2/g from 0.911 m2/g. Accompanying the increase in calcination temperature, the inhibition of Ni2+ doping on the growth and crystallization of grains decreases. When the temperature is lower than 750 °C, Ni atoms replace the Ti atoms that are substituted for Li atoms in the original pure Li layer, forming lattice defects, resulting in the disappearance of (002) and (−131) diffraction peaks for Li2TiO3, the reduced ordering of crystal structure, a decrease in the interplanar spacing of the (002) plane, lattice expansion and an increase in the particle size to 100–200 nm. When the temperature exceeds 750 °C, with the increase of calcination temperature, the influence of Ni doping on the growth and crystallinity of grains decreases, and the (002) crystal surface starts to grow again.
Preparation of Ni-Doped Li2TiO3 Using an Inorganic Precipitation–Peptization Method