Cu-Sn binary particles were generated via spray pyrolysis from metal salt precursors with ethylene glycol as the co-solvent and reducing agent. The morphology, crystallinity, and elemental distribution of particles were tunable by changing the reaction temperature, residence time, and quench gas flow rate. Hollow porous particles were fabricated with a higher Sn concentration on the particle surface when the furnace set point was 500 C, while solid particles with a lower surface Sn concentration were generated when the furnace set point was 1000 C. Particles with spherical morphologies were obtained at long residence time conditions (4.5 s). Cu-Sn binary particles with irregular structures (e.g., pores on the particle surface, fragmented spherical particles, and lamellar fragments) were formed at short residence time conditions (0.92 s). A possible spray pyrolysis mechanism was proposed that incorporates chemical reaction steps and structural progression. By this mechanism, the metal salts are believed to sequentially undergo hydrolysis to metal hydroxides, decomposition to metal oxides, reduction to metals, and finally diffusion of Sn into the Cu matrix to generate the Cu-Sn solid solution.

Two series of ordered mesoporous organosilica (OMO) SBA-15 materials with surface and bridging groups were fabricated by varying the organic precursor addition at different synthesis stages. The consequence of the delayed introduction of organic precursor on the structural and adsorption properties of the resulting OMOs was investigated. The OMOs studied were synthesized via co-condensation of tetraethyl orthosilicate (TEOS) and ureidopropyltrimethoxysilane (UPS) as well as TEOS and bis(triethoxysilylpropyl) disulfide (BTDS) in the presence of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer Pluronic P123 (EO 20 PO 70 EO 20 ). The aforementioned OMOs were characterized by nitrogen adsorption-desorption isotherms at −196°C and powder X-ray diffraction (XRD). Nitrogen adsorption isotherms were used to estimate the pore volume, mesopore diameter and the BET specific surface area, whereas the XRD data provided information about structural ordering and unit cell of the samples studied.Keywords Channel-like mesostructures · Ordered mesoporous organosilicas · Nitrogen adsorption · SBA-15 · Ureidopropyl surface group · Bis(propyl)disulfide bridging group Ryan Felix, undergraduate student from Oberlin College (Oberlin, OH, USA) participating in the NSF-REU program during Summer 2006.Abbreviations a unit cell parameter (nm) P N/S nitrogen or sulfur weight percentages obtained from elemental analysis (%) S BET BET specific surface area (m 2 /g) V c volume of micropores and interconnecting pores of the diameter below 4 nm (cc/g) V p volume of primary pores (cc/g) V t single-point pore volume (cc/g) w KJS mesopore diameter calculated by the KJS method (nm)

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