Synthesis of Pt-containing mesoporous silica using Pt precursor as a pore-forming agent

We synthesized Pt nanoparticle-containing mesoporous silica in a one-pot process using tetraammineplatinum(II) hydroxide (TPH) precursor as a pore-forming agent and silica nanospheres as a silica source. The TPH precursor was added into as-prepared colloidal silica sol with silica nanospheres (SN) of about 8 nm in particle diameter, to obtain the SN–TPH sol. During drying process of the SN–TPH sol, an amorphous SN–TPH nanocomposite was formed via hydrogen-bonding interaction between silanol groups and amine groups of the TPH precursor. The hydrogen-bonding interaction was confirmed by thermal gravimetry and differential thermal analysis (TG–DTA) profiles and Fourier transform infrared (FTIR) spectra. Using the TPH precursor as a pore-forming agent, incorporation of the Pt nanoparticles into the mesoporous silica can be simultaneously achieved with the synthesis of the mesoporous silica in a one-pot process. In addition, Pt nanoparticle size and pore diameter of the mesoporous Pt/silica were simultaneously controlled by simply varying the concentration of the TPH precursor. The pore diameter of the mesoporous silica was easily controlled from 3.2 nm to 6.5 nm with an increase in the TPH concentration.