Yali Liu, Pengfei Zhang, Junmin Liu, Tao Wang, Qisheng Huo, Li Yang, Lei. Sun,*, Zhen-An Qiao,*, and Sheng Dai *, ASSOCIATED CONTENT

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1 ASSOCIATED CONTENT Supporting Information Gold Cluster-CeO 2 Nanostructured Hybrid Architectures as Catalysts for Selective Oxidation of Inert Hydrocarbons Yali Liu, Pengfei Zhang, Junmin Liu, Tao Wang, Qisheng Huo, Li Yang, Lei Sun,*, Zhen-An Qiao,*, and Sheng Dai *, Figure S1. UV-vis spectrum of a) Au 25 and b) Au 144 clusters in chloroform.

2 Figure S2. TEM a), aberration-corrected HAADF-STEM b)-c) images of Au 2 nanospheres (0.2 wt % loading rate of Au 144 clusters) and the corresponding elemental mapping for Au, O, Ce of Au 2 nanospheres (0.2 wt % loading rate of Au 144 clusters).

3 Figure S3. a) XRD patterns and b) N 2 adsorption/desorption isotherms of different Au 25 clusters loading amount on mesoporous CeO 2 nanospheres. The inset in b shows pore size distributions of samples. Figure S4. TEM images of a) Au 25 /mceo 2 b) Au 144 /mceo 2 and c) Au NPs/mCeO 2 nanospheres (the red circle areas are gold nanoparticles). d) N 2 adsorption/desorption isotherms and (inset) pore size distributions of Au NPs/mCeO 2 (black line) Au 25 /mceo 2 (blue line) and Au 144 /mceo 2 (red line). Isotherms of Au 25 /mceo 2 and Au 144 /mceo 2 have been offset by 10 and 20, respectively, along the vertical axis for clarity.

4 Figure S5. a) The FTIR spectra and b) TGA-MS analysis of the Au 2, and Au 2 nanospheres (0.2 wt % loading rate of gold clusters). Figure S6. TEM images of Au 2 nanospheres (0.2 wt % loading rate of Au 25 clusters) after calcination at different temperatures a) 300 C, b) 500 C and c) 700 C, and d) the corresponding XRD patterns.

5 Figure S7. The reusing tests of Au 2 nanospheres in the tetrahydronaphthalene oxidation. Figure S8. TEM images of a) Au 2 and b) Au 2 samples (0.1 wt % loading rate of gold clusters) after cyclic catalysis experiment. c) XRD patterns and d) N 2 adsorption/desorption isotherms for these samples.

6 Figure S9. Three-dimensional charge density difference with isosurface value of e/bohr3 of the Au 2 system. Green and blue colors represent losing and gaining electrons, respectively. Figure S10. Optimized geometries for positive Au 25 cluster. Green color represents the middle atomic layer.

7 Figure S11. The reaction kinetics plots for the oxidation by 10 mg Au 2 catalyst (0.1 wt % loading rate of Au 25 clusters). Reaction conditions: a) tetrahydronaphthalene 10 ml, 100 C. b) diphenylmethane 10 ml, 140 C. c) indane 10 ml, 110 C. d) ethylbenzene 10 ml, 120 C. C o : original concentration of substrate; C t : concentration of substrate at t. Table S1. C H N elemental analysis of gold clusters@mceo 2 (0.2 wt % loading rate of gold clusters) after calcination. Name N(%) C(%) H(%) S(%)

8 Au Au Table S2. Comparison of ethylbenzene oxidation activity of the Au 2 catalysts with other reported catalytic systems. Catalyst T/P Solvent Oxidant Conversion (%) Acetophenone Selectivity (%) Phenylethyl alcohol TOF (h -1 ) references MnCO3 190 C /1MPa free O n.d. [32] Mn-N-C@ SiO2 120 C /0.8MPa free O n.d. n.d. 3,228.6 [33] Au/LDH 140 C /3MPa free TBHP n.d. [34] CeO2 160 C /1.2MPa free TBHP n.d. [35] Ce0.5Mn0.5Ox 120 C /10bar CH3CN O n.d. n.d. n.d. [38] sub-au/lc- 0.5%Pd@C- GluA C /1atm free O n.d. n.d. 245 [36] CoSBA C /1atm CH4CN TBHP n.d. n.d. [37] Au25/mCeO2 120 C/1atm free O ,956 this work

9 Table S3. Aerobic oxidation of saturated hydrocarbons by gold 2 (0.1 wt % loading rate of gold clusters) catalysts. Entry Catalyst Substrate Product (Sel. %) T ( C) TOF (h -1 ) Con. (%) 1 * Au 2 Indane 1-Indanol (81) 1-Indanone (18) , * Au 2 Indane 1-Indanol (40) 1-Indanone (52) , * Au 2 Indane 1-Indanol (14) 1-Indanone (47) , * Au 2 Indane 1-Indanol (74) 1-Indanone (25) , * Au 2 Tetrahydronaphthalene a-naphthol (36) α-tetralone (63) , * Au 2 Tetrahydronaphthalene a-naphthol (22) α-tetralone (77) , * Au 2 Diphenylmethane Benzophenone (99) , * Au 2 Diphenylmethane Benzophenone (99) , Au 2 Cyclohexene 2-Cyclohexen-1-ol (33) 2-Cyclohexen-1-one (32) , Reaction conditions: * Substrate 10 ml, 10 mg of gold clusters@mceo 2 nanospheres, O 2 1 atm, 24 h; Substrate 10 ml, 10 mg of gold clusters@mceo 2, O 2 10 atm, 7 h. TOF = [reacted mol hydrocarbons]/[(total mol gold) (gold dispersion) (reaction time)]. * The TOFs were measured after the first 0.5 h of reaction. The TOFs were calculated after 7 h of the reaction. Conv., conversion; Sel., selectivity.

10 Table S4. Total electronic energy for Au + 25 (E atom ), O 2 binding energy to the cluster (E B ), barrier to dissociation for rate-determining step (E # ), O-O distance for O 2 (d O-O ) and net Bader charge on each O atom for reactant (N O2 ) and final product (N 2O ). E atom E b E # d O-O N O2 N 2O Au + 25 (ev/atom) (ev) (ev) (Å) (e) (e) Cluster I / /-0.67 Cluster II / /-0.71 Computational details The DFT calculation for Au 25 cluster was performed using the Vienna Ab initio Simulation Package (VASP) code, 1-2 with exchange correlation effects being described by the Perdew Burke Ernzerhof (PBE) version of the generalized gradient approximation (GGA). 3 A plane-wave basis set with kinetic-energy cutoff of 450 ev has

11 been used. The convergence criterion for the geometry optimizations was set to be 0.02 ev/å on force. A Monkhorst-Pack k-point grid was used in our studies. For the Au 2 model, CeO 2 (200) substrate consisted of 3 atomic layers (two bottom layers fixed, the other one free), the size of the surface supercell was 8 4. The Au 25 cluster was placed on the CeO 2 (200) surface. Different with the Au 25 cluster calculation, we used the PW91 type of generalized gradient approximation (GGA) 4 as the exchange correlation functional and added the simplified approach to the LSDA+U, introduced by Dudarev et al. 5 A Monkhorst-Pack k-point grid was used in this calculation. To better describe the dispersion interaction within oxygen adsorption systems, van der Waals correction 6 and spin polarization were considered in the calculations. The cluster was placed in the center of a large unit cell (20 Å 20 Å 20 Å), with a vacuum space of 10 Å between each other in all directions. The climbing images nudged elastic band (CI-NEB) algorithm was employed to search for transition states (TSs). For the search TSs, the same force threshold as the geometrical optimization was used. Table S5. The gold dispersion of gold-based catalysts.

12 Sample Gold dispersion (%) Au Au Au 25 /mceo Au 144 /mceo References 1. Kresse, G.; Furthmüller, J., Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set. Comp. Mater. Sci. 1996, 6, Kresse, G.; Hafner, J., Ab-initio molecular dynamics for liquid metals. Phys. Rev. B 1993, 47, Perdew, J. P.; Burke, K.; Ernzerhof, M., Generalized gradient approximation made simple. Phys. Rev. Lett. 1996, 77, Perdew J. P.; Chevary J. A.; Vosko S. H.; Jackson K. A.; Pederson M.; Singh R. D.; Fiolhais J. C., Atoms, molecules, solids, and surfaces: Applications of the

13 generalized gradient approximation for exchange and correlation. Phys. Rev. B 1992, 46, Dudarev, S. L.; Botton, G. A.; Savrasov, S. Y.; Humphreys, C. J.; Sutton, A. P., Electron-energy-loss spectra and the structural stability of nickel oxide: An LSDA+ U study. Phys. Rev. B 1992, 57, Grimme, S., Semiempirical GGA-type density functional constructed with a longrange dispersion correction. J. Comput. Chem. 2006, 27,