Formation of Titania-Silica Mixed Oxides in Solvent Mixtures and Their Influences for the Photocatalytic CO2 Conversion to Hydrocarbon.

TiO2-SiO2 mixed oxide photocatalyst materials responsive to simulated solar light illumination have been synthesized by sol-gel method in various polar and nonpolar organic solvent mixtures. The photocatalysts were characterized by numerous experimental techniques and investigated for the photocatalytic conversion of CO2 to CH4. The TiO2-SiO2 mixed oxide photocatalysts prepared in the presence of nonpolar aromatic solvents such as xylene, toluene or benzene along with ethanol show high surface area, huge mesoporosity and enormous pore volume compared to the materials conventionally synthesized in a mixture of ethanol and hexane.

Highly fluorescent peptide nanoribbon impregnated with Sn-porphyrin as a potent DNA sensor.

Highly fluorescent and thermo-stable peptide nanoribbons (PNRs) were fabricated by solvothermal self-assembly of a single peptide (D,D-diphenyl alanine peptides) with Sn-porphyrin (trans-dihydroxo[5,10,15,20-tetrakis(p-tolyl)porphyrinato] Sn(IV) (SnTTP(OH)2)). The structural characterization of the as-prepared nanoribbons was performed by transmitting electron microscopy (TEM), scanning electron microscopy (SEM) and atomic force microscopy (AFM), FT-IR and Raman spectroscopy, indicating that the lipophilic Sn-porphyrins are impregnated into the porous surface formed in the process of nanoribbon formation through intermolecular hydrogen bonding of the peptide main chains. Consequently the Sn-porphyrin-impregnated peptide nanoribbons (Sn-porphyrin-PNRs) exhibited typical UV-visible absorption spectrum of the monomer porphyrin with a red shifted Q-band, and their fluorescence quantum yield was observed to be enhanced compared to that of free Sn-porphyrin.