Electronic Supplementary Information

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1 Electronic Supplementary Information One-step-impregnation hard templating synthesis of highsurface-area nanostructured mixed metal oxides (, and Cu/CeO 2 ) Hoang Yen a, Yongbeom Seo b, Rémy Guillet-Nicolas a, Serge Kaliaguine c and Freddy Kleitz a* Mixed metal oxide replica Filtration, drying, calcination, removal of silica template with NaOH 2M Nitrate salt precursors + Organic solvent (n-hexane, cyclohexane, n- heptane) + Mesoporous silica Reflux at 7-8 o C, 12h Fig. S1 Schematic representation of the hard templating synthesis of mixed metal oxides using nitrate precursors in the presence of organic solvent under reflux. Prior to the reflux step, the given nitrate salts in stoichiometric proportion are pre-mixed together with the mesoporous silica powder and ground in an agate mortar in the presence of the solvent. Note here that the metal nitrate hydrate salts can be liquefied at lower temperature on the surface of the solid than in the bulk when they are pressed and ground. Therefore, this wet grinding step could serve as a driving force for reducing melting point and thus increasing homogeneity of the mixture. For related references, see Y. M. Wang, Z. Y. Wu, H. J. Wang and J. H. Zhu, dv. Funct. Mater., 6, 16, 2374; Y.-C. Xie and Y.-Q. Tang, dv. Catal. 199, 37, 1; and V. I. Levitas,. F. Henson, L.. Smilowitz and. W. say, Phys. Rev. Lett. 4, 92,

2 1 dsorption Desorption dsorption Desorption. 1. C 8 Volume adsorbed (cm3g-1) Volume adsorbed (cm3g-1) Volume adsorbed (cm3g-1) P/P dsorption Desorption P/P P/P Fig. S2 N2 adsorption-desorption isotherms at -196 C of mesoporous silicas: () S15 silica aged at 1 oc, () KIT-6 silica aged at 1 oc, (C) MCM-48 silica nanospheres (Micromeretics SP 21). C theta (o) theta (o) o 2 theta ( ) Fig. S3 Low-angle XRD patterns of mesoporous silicas: () S-15 aged at 1oC, () KIT-6 aged at 1 oc, (C) MCM-48 nanospheres (Rigaku Multiplex, operated at 2 kw, using Cu Kα radiation). 1 nm C 5 nm nm Fig. S4 Representative TEM images of the mesoporous silica templates: () S-15 aged at 1 oc, () KIT-6 aged at 1oC, (C) MCM-48 nanospheres (JEOL JEM 123 operated at 12kV). 2

3 Cu(1)/CeO 2 Cu(3)/CeO 2 1 nm nm Fig. S5 TEM images of Cu(1)/CeO 2 and Cu(3)/CeO 2 prepared using KIT-6 as a template (as indicated). Fig. S6 HRTEM images of () nanocast using KIT-6 template () nanocast prepared using KIT-6 as the template and (C) nanowires from S-15 (the images were obtained using Philips F2 Tecnai instrument, 16kV). 3

4 1 nm 1 nm Fig. S7 TEM images of Cu(2)/CeO 2 prepared using S-15 as the template with different loadings of nitrate precursor/silica: () 1.5g/g silica, () 2g/g silica. Cu(2)/CeO theta ( o ) Fig. S8 Wide-angle powder XRD patterns for the mixed metal oxides prepared in this work prepared using MCM-48 as the template (as indicated) (ruker SMRT PEXII X-ray diffractometer with a Cu K α radiation). 4

5 (d) (c) (b) (a) theta ( o ) Fig. S9 Low-angle XRD patterns of nanocast mixed oxides prepared using S-15 as the template: (a) isolated nanowires, (b) mesostructured Cu(2)/CeO 2, (c) mesostructured, (d) nanowire bundles (Rigaku Multiplex, operated at 2 kw, using Cu K α radiation). Cu(2)/CeO theta ( o ) Fig. S1 Low-angle XRD patterns of nanocast mixed oxides prepared using MCM-48 nanospheres as the template (as indicated) (ruker SMRT PEXII X-ray diffractometer with a Cu K α radiation). 5

6 1 8 Volume adsorbed (cm 3 g -1 ) Cu(2)/CeO 2 Volume adsorbed (cm 3 g -1 ) Cu(2)/CeO P/P o P/P o Fig. S11 N 2 adsorption-desorption isotherms measured at -196 C for the mixed metal oxides prepared using () KIT-6 silica as a template, and () S-15 as a template (as indicated) (SP 21). 7 Volume adsorbed (cm 3 g -1 ) 5 3 Pore size distribution (cm3g-1nm-1) + +5 Cu(2)/CeO Pore size (nm) Cu(2)/CeO P/P Fig. S12 N 2 adsorption-desorption isotherms at -196 C and respective NLDFT pore size distributions (inset) deduced from the adsorption branch for the nanocast mixed metal oxides (as indicated). 6

7 25.5 Volume adsorbed (cm 3 g -1 ) dv/dd (cm 3 g -1 nm -1 ) P/P o Pore diameter (nm) Fig. S13 N 2 sorption isotherm and respective NLDFT pore size distribution (adsorption branch) of single metal oxide Co 3 nanocast prepared using KIT-6 as the template. nm theta ( o ) Fig. S14 TEM image of Co 3 prepared using KIT-6 as the template (left) and wideangle XRD pattern of Co 3 using KIT-6 as the template (right). 7

8 C 1 nm nm nm D nm E 1 nm Fig. S15 TEM images of Cu(2)/CeO2 prepared using S-15 as the template in the presence of various solvents and at different reflux temperatures, with a fixed precursor loading of 2.5g/1g silica: () n-hexane at 7 oc, () cyclohexane at 7 oc, (C) n-heptane at 7 oc, (D) cyclohexane at 8 oc, and (E) n-heptane at 1 oc. nm nm Fig. S16 TEM images of () Cu(2)/CeO2 nanocast prepared using S-15 as the template without reflux process (the nitrate precursors were ground with silica and calcined at 5 oc for 5h). () Cu(2)/CeO2 prepared using S-15 as the template without reflux process (the nitrate precursors were ground with silica and pre-heated at 7 oc before calcination at 5 oc for 5h). 8

9 nm Fig. S17 TEM image of Cu(2)/CeO 2 nanocast prepared using S-15 as the template via wet impregnation method using ethanol to dissolve the metal precursors. 9

10 Table S1. Physicochemical parameters of the different mesoporous mixed metal oxides derived from nitrogen physisorption measurements at -196 C. Samples a S ET b V t c d NLDFT (m 2 g -1 ) (cm 3 g -1 ) (nm) Cu(2)/CeO 2 -S S S Cu(2)/CeO 2 -KIT KIT KIT Cu(2)/CeO 2 -MCM MCM MCM a S ET, apparent ET specific surface area deduced from the isotherm analysis in the relative pressure range from.5 to.2; b V t, total pore volume at relative pressure.95; c d NLDFT, pore diameter calculated from the adsorption branch (NLDFT kernel of metastable adsorption isotherms). 1