Shell-adjustable hollow ‘soft’ silica spheres as a support for gold nanoparticles

Hollow silica spheres composed of a ‘soft’ nanosheet network exhibit a large surface area and pore volume and are used here as a support for gold nanoparticles. The nanosheet morphology changes upon binding of gold nanoparticles and facilitates their fixation in the shell. The gold nanoparticles remain well dispersed in the shell even after heat treatment at 500 °C. It is also possible to control easily the loading ratio of gold in the flake-shell sphere by varying the quantity of chloroauric acid added during the preparation. The stably confined but accessible gold nanoparticles in the flake-shell sphere show high performance for the catalytic reduction of nitrophenols with high conversion and good reusability. This new composite structure could also be useful for various other catalytic processes.

[1]  G. Hutchings,et al.  Hydrochlorination of acetylene using gold catalysts: A study of catalyst deactivation , 1991 .

[2]  C. Copéret,et al.  Gold nanoparticles supported on passivated silica: access to an efficient aerobic epoxidation catalyst and the intrinsic oxidation activity of gold. , 2009, Journal of the American Chemical Society.

[3]  H. Koga,et al.  Topochemical synthesis and catalysis of metal nanoparticles exposed on crystalline cellulose nanofibers. , 2010, Chemical communications.

[4]  Hiroshi Sano,et al.  Novel Gold Catalysts for the Oxidation of Carbon Monoxide at a Temperature far Below 0 °C , 1987 .

[5]  M. Haruta,et al.  A three-dimensional mesoporous titanosilicate support for gold nanoparticles: vapor-phase epoxidation of propene with high conversion. , 2004, Angewandte Chemie.

[6]  K. B. Yoon,et al.  Synthesis of ideal AM-6 and elucidation of V4+-to-O charge transfer in vanadate quantum wires. , 2010, Angewandte Chemie.

[7]  Yun Yan,et al.  Self-assembled laminated nanoribbon-directed synthesis of noble metallic nanoparticle-decorated silica nanotubes and their catalytic applications , 2012 .

[8]  R. Holze,et al.  Spectroelectrochemical investigation of the adsorption and oxidation of unsaturated C4-alcohols , 2000 .

[9]  T. Tabakova,et al.  Gold, silver and copper catalysts supported on TiO2 for pure hydrogen production , 2002 .

[10]  K. Chao,et al.  Highly Dispersed Metal Nanoparticles in Functionalized SBA-15 , 2003 .

[11]  Avelino Corma,et al.  Supported gold nanoparticles as catalysts for organic reactions. , 2008, Chemical Society reviews.

[12]  Katsuhiko Ariga,et al.  Nanoarchitectonics for mesoporous materials , 2012 .

[13]  G. Hutchings.  Vapor phase hydrochlorination of acetylene: Correlation of catalytic activity of supported metal chloride catalysts , 1985 .

[14]  Itamar Willner,et al.  Integrated nanoparticle-biomolecule hybrid systems: synthesis, properties, and applications. , 2004, Angewandte Chemie.

[15]  Masatake Haruta,et al.  Gold catalysts prepared by coprecipitation for low-temperature oxidation of hydrogen and of carbon monoxide , 1989 .

[16]  K. Loh,et al.  Au nanoparticles dispersed on functionalized mesoporous silica for selective oxidation of cyclohexane , 2010 .

[17]  Katsuhiko Ariga,et al.  Flake-shell capsules: adjustable inorganic structures. , 2012, Small.

[18]  D. Fernig,et al.  Determination of size and concentration of gold nanoparticles from UV-vis spectra. , 2007, Analytical chemistry.

[19]  Masatake Haruta,et al.  Size- and support-dependency in the catalysis of gold , 1997 .

[20]  N. Pradhan,et al.  Silver nanoparticle catalyzed reduction of aromatic nitro compounds , 2002 .

[21]  Qiuming Gao,et al.  Intensively competitive adsorption for heavy metal ions by PAMAM-SBA-15 and EDTA-PAMAM-SBA-15 inorganic-organic hybrid materials , 2007 .

[22]  S. Ghosh,et al.  Bimetallic Pt–Ni nanoparticles can catalyze reduction of aromatic nitro compounds by sodium borohydride in aqueous solution , 2004 .

[23]  G. Somorjai,et al.  Thermally stable Pt/mesoporous silica core-shell nanocatalysts for high-temperature reactions. , 2009, Nature materials.

[24]  F. Schüth,et al.  A systematic study of the synthesis conditions for the preparation of highly active gold catalysts , 2002 .

[25]  A. Hashmi,et al.  Gold catalysis in total synthesis. , 2008, Chemical Society reviews.

[26]  Jeong‐Myeong Ha,et al.  Synthesis and characterization of accessible metal surfaces in calixarene-bound gold nanoparticles. , 2009, Langmuir : the ACS journal of surfaces and colloids.

[27]  J. Teles,et al.  Cationic Gold(I) Complexes: Highly Efficient Catalysts for the Addition of Alcohols to Alkynes. , 1998, Angewandte Chemie.

[28]  Lifang Chen,et al.  Intercalation of aggregation-free and well-dispersed gold nanoparticles into the walls of mesoporous silica as a robust "green" catalyst for n-alkane oxidation. , 2009, Journal of the American Chemical Society.

[29]  Charles T. Campbell,et al.  The Active Site in Nanoparticle Gold Catalysis , 2004, Science.

[30]  A. Corma,et al.  Chemoselective Hydrogenation of Nitro Compounds with Supported Gold Catalysts , 2006, Science.

[31]  P. Claus.  Heterogeneously catalysed hydrogenation using gold catalysts , 2005 .

[32]  G. Hutchings,et al.  Hydrochlorination of acetylene using a supported gold catalyst: A study of the reaction mechanism , 2007 .

[33]  G. Somorjai,et al.  Synthetic insertion of gold nanoparticles into mesoporous silica , 2003 .

[34]  S. Mann,et al.  Covalent coupling of an organic chromophore into functionalized MCM-41 mesophases by template-directed co-condensation , 1998 .

[35]  H. Hinode,et al.  Roles of nano-sized Au in the reduction of NOx by propene over Au/TiO2: An in situ DRIFTS study , 2010 .

[36]  A. Hashmi,et al.  Gold catalysis in total synthesis--an update. , 2012, Chemical Society reviews.

[37]  I. Arslan,et al.  Gold nanoparticle-catalyzed reduction in a model system: Quantitative determination of reactive heterogeneity of a supported nanoparticle surface , 2012 .

[38]  S. Hamoudi,et al.  Synthesis of Gold Catalysts Supported on Mesoporous Silica Materials: Recent Developments , 2011 .

[39]  Masatake Haruta,et al.  Catalysis of Gold Nanoparticles Deposited on Metal Oxides , 2002 .

[40]  R. Doong,et al.  Bifunctional Au−Fe3O4 Heterostructures for Magnetically Recyclable Catalysis of Nitrophenol Reduction , 2011 .

[41]  Byeong‐Su Kim,et al.  Hybrid gold nanoparticle-reduced graphene oxide nanosheets as active catalysts for highly efficient reduction of nitroarenes , 2011 .

[42]  Ferdi Schüth,et al.  Support effect in high activity gold catalysts for CO oxidation. , 2006, Journal of the American Chemical Society.

[43]  Katsuhiko Ariga,et al.  Effect of molecular weight of polyethyleneimine on loading of CpG oligodeoxynucleotides onto flake-shell silica nanoparticles for enhanced TLR9-mediated induction of interferon-α , 2012, International journal of nanomedicine.

[44]  T. García,et al.  Stable anchoring of dispersed gold nanoparticles on hierarchic porous silica-based materials , 2010 .

[45]  Bernard Delmon,et al.  Low-Temperature Oxidation of CO over Gold Supported on TiO2, α-Fe2O3, and Co3O4 , 1993 .

[46]  Lifang Chen,et al.  Nanoscale gold intercalated into mesoporous silica as a highly active and robust catalyst , 2012, Nanotechnology.

[47]  Katsuhiko Ariga,et al.  Gold nanoparticles embedded in a mesoporous carbon nitride stabilizer for highly efficient three-component coupling reaction. , 2010, Angewandte Chemie.

[48]  T. Tabakova,et al.  FTIR study of low-temperature water-gas shift reaction on gold/ceria catalyst , 2003 .

[49]  A. Corma,et al.  Supported gold catalyzes the homocoupling of phenylboronic acid with high conversion and selectivity. , 2005, Angewandte Chemie.

[50]  B. Gates,et al.  Gold Nanoclusters Supported on MgO: Synthesis, Characterization, and Evidence of Au6 , 2001 .

[51]  L. Prati,et al.  Selective oxidation using gold. , 2008, Chemical Society reviews.