Supporting Information for

Transcription

1 Supporting Information for Microporous Organic Network Hollow Spheres: Useful Templates for Nanoparticulate Co 3 O 4 Hollow Oxidation Catalysts Narae Kang, Ji Hoon Park, Mingshi Jin, Nojin Park, Sang Moon Lee, Hae Jin Kim, Ji Man Kim,* and Seung Uk Son* Department of Chemistry and Department of Energy Science, Sungkyunkwan University, Suwon , Korea, and Korea Basic Science Institute, Daejeon , Korea Experimental Section TEM images were obtained using a JEOL 2100F unit operated at 200 kv. The adsorption-desorption isotherms for N 2 (77 K) were recorded using BELSORP II-mini volumetric adsorption equipment. PXRD patterns were obtained using a Rigaku MAX-2200 and filtered Cu-Ka radiation. The solid phase 13 C-NMR spectra were obtained on a Bruker 400 MHz Solid State Bruker DSX NMR spectrometer at the Korea Basic Science Institute (Daegu). The TGA curves were obtained by a Seiko Exstar The XPS spectrum was obtained using a Thermo VG and Monochromatic Al-Kα radiation. Synthetic procedure of H-MONs: Silica spheres were prepared for use as a template. [ref. 12 in text] Tetraethyl orthosilicate (14 ml) in ethanol (56 ml) was added to a mixture of ammonia solution (28~30%, 7 ml), ethanol (144 ml) and water (18 ml). The mixture was stirred for 2 hours. The silica spheres produced were isolated by centrifugation, washed with ethanol and dried under vacuum for 24 hours. For the preparation of H-MON-2, silica spheres (300 mg) were dispersed in a mixture of toluene (15 ml) and triethylamine (TEA, 15 ml). The catalysts, Pd(PPh 3 ) 2 Cl 2 (8.4 mg, mmol) and CuI (2.2 mg, mmol) were added. The solution was stirred for 1 hour at room temperature. Tetra(4-ethynylphenyl)methane (50 mg, 0.12 mmol) and 1,4- diiodobenzene (80 mg, 0.24 mmol) were added. The reaction mixture was heated at 100 o C for 48 hours. The resultant yellow solids (SiO were retrieved by centrifugation, washed with acetone, methanol, methylene chloride, and diethylether, and dried under vacuum overnight. The SiO (250 mg ~ 300 mg) was added to HF solution (48%, 15 ml) and the reaction mixture was stirred for 2 hours. The resultant materials (H-MON-2) were retrieved by centrifugation, washed with water, ethanol, acetone and diethylether, and dried under vacuum for 24 hours. For the preparation of H-MON-1 and H-MON-3, mixtures of 20 ml/10 ml and 0 ml/30 ml toluene/tea were used as solvents, respectively, instead of 15 ml/15 ml toluene/tea for H-MON-2. Other procedures were the same as those for H-MON-2. For the preparation of H-MON-4, 400 mg of silica was used instead of 300 mg of silica for H-MON-2. Synthetic procedure for nanoparticulate Co 3 O 4 hollow spheres: H-MON-2 (50 mg) was dispersed in toluene (4mL). Co 2 (CO) 8 (30 mg, mmol) in toluene (10 ml) was added. The reaction mixture was heated at 100 o C overnight. During this process, the dark solution became transparent. The resultant dark yellow solids were retrieved by centrifugation, washed with toluene, and dried under vacuum for 3 hours. Then, the solids were heated at 500 o C for 5 hours under air to form black powders. S1

2 Catalytic reaction procedure for H2O2 oxidation: H2O2 solution (0.2 M, 25 ml) was added to Co3O4 catalysts (20 mg) in a 100 ml flask. The volume of gas was measured every 1 minute using a burette connected with the reaction glassware. The temperature of reaction mixture was maintained at 25 oc using a temperature-controlled water bath. Considering the vapor pressure of water at 25 oc, the oxygen volume was calculated.[ref. 16 in text] It is known that 1 mole of oxygen gas is generated through the decomposition of 2 mol of H2O2 by Co3O4 catalysts with first-order reaction kinetics. [ref. 16 in text] Based on these, rate constants were calculated through the plot of ln[h2o2]/[h2o2]o versus time. The slope value corresponds to k. Figure S1. TEM image of the silica templates. Figure S2. TEM image of the MON materials obtained using 500 mg silica templates. S2

3 Figure S3. N 2 adsorption/desorption isotherms at 77K, pore size distribution diagrams of H-MONs. H-MON-1 H-MON-2 H-MON-3 H-MON m 2 /g 648 m 2 /g 572 m 2 /g 672 m 2 /g H-MON-1 H-MON-2 H-MON-3 H-MON cm 3 /g 0.39 cm 3 /g 0.38 cm 3 /g 0.41 cm 3 /g S3

4 Figure S4. TGA curves of H-MON-1~ ºC 240 ºC H-MON-3 H-MON-2 H-MON-1 H-MON-4 Figure S5. PXRD Patterns of H-MON-1~4. S4

5 Figure S6. TEM images (a), PXRD patterns (b), and XPS spectra (c) of the nanoparticulate Co 3 O 4 hollow spheres before and after (five runs) catalyzing the H 2 O 2 oxidation. (a) Original Co 3 O 4 hollows used for catalysis in Figure 4 in text Recovered Co 3 O 4 hollows after five runs (b) (c) S5