Supporting Information

Transcription

1 Supporting Information Yb 3 O(OH) 6 Cl.2H 2 O An anion exchangeable hydroxide with a cationic inorganic framework structure Helen V. Goulding, a Sarah E. Hulse, a William Clegg, b Ross W. Harrington, b Helen Y. Playford, c Richard I. Walton c and Andrew M. Fogg a * a Department of Chemistry, University of Liverpool, Crown Street, Liverpool, L69 7ZD, U.K. b School of Chemistry, Newcastle University, Newcastle upon Tyne, NE1 7RU, U.K. c Department of Chemistry, University of Warwick, Coventry, CV4 7AL, U.K. S1

2 Experimental Details Synthesis Yb 3 O(OH) 6 Cl.2H 2 O was prepared via a hydrothermal synthesis. Typically, 7.5 ml of a 0.44 M aqueous solution of YbCl 3.nH 2 O was added to 2.5 ml of an aqueous solution containing 2.1 M NaOH and 1.44 M NaCl. A gelatinous precipitate was formed instantaneously and the resulting mixture was treated hydrothermally at 220 ºC for 14 hours. The resulting product was then filtered, washed with de-ionized water and ethanol before being dried in air at room temperature. Anion exchange reactions were performed between Yb 3 O(OH) 6 Cl.2H 2 O and a threefold molar excess of the following anions in aqueous solution: nitrate, carbonate oxalate and succinate. In each case the reaction mixture was stirred at room temperature overnight before being filtered, washed with de-ionized water and ethanol and left to dry in air. Characterization Powder X-ray diffraction patterns were recorded with Cu Kα 1 radiation on a Stoe Stadi-P diffractometer in either Bragg-Brentano or Debye-Scherrer geometry. A combination of thermogravimetric analysis (TGA) and elemental analysis was used to determine the stoichiometry of the materials. CHN analysis was performed by Elemental Microanalysis, Okehampton, Devon, EX20 1UB, U.K. Fourier transform infra-red (FTIR) spectra were obtained using a Perkin Elmer Spectrum 100 spectrometer fitted with the Spectrum 100 Universal Diamond/ZnSe ATR. In situ powder X-ray diffraction data were recorded using a Bruker D8 diffractometer equipped with an Anton Parr XRK900 reaction chamber and operating with Cu Kα radiation. Data were measured using a VÅNTEC-1 solid-state detector in scanning mode. The sample was packed into a ceramic holder and data measured in S2

3 theta-theta geometry with a flow of dry nitrogen was passed through the chamber while being heated between room temperature and 550 ºC. The single-crystal X-ray diffraction analysis of Yb 3 O(OH) 6 Cl.2H 2 O was performed on data collected on Beamline I19 of the Diamond Light Source, using a Crystal Logics kappa-geometry diffractometer and a Rigaku Saturn 724+ CCD detector with a Cryostream cooler (at 120 K); Rigaku CrystalClear was used to record images, Bruker APEX2 for data integration, and SHELXTL for structure solution and refinement. The synchrotron X-ray wavelength was Å. Non-merohedral twinning prevented merging of symmetry-equivalent data prior to refinement. Elemental Analysis Table S1 Elemental Analysis Compound Observed (%) Calculated (%) Yb 3 O(OH) 6 Cl.2H 2 O H (1.14) H (1.42) Lu 3 O(OH) 6 Cl.2H 2 O H (1.20) H (1.41) C (0.33) Yb 3 O(OH) 6 (CO 3 ) 0.5.2H 2 O H (1.21) C (0.71) H (1.43) C (0.85) Yb 3 O(OH) 6 (C 2 O 4 ) 0.5.3H 2 O H (1.20) C (1.86) H (1.64) C (1.63) Yb 3 O(OH) 6 (C 4 H 4 O 4 ) 0.5.H 2 O H (1.48) C (3.66) H (1.41) C (3.37) S3

4 Characterizing data for Yb 3 O(OH) 6 Cl.2H 2 O Intensity (Arb. units) * * * θ (º) Figure S1 Powder XRD patterns of Yb 3 O(OH) 6 Cl.2H 2 O (a) calculated and (b) experimental. * - unknown impurity S4

5 Sample Weight (%) Temperature (ºC) Figure S2 TGA trace for Yb 3 O(OH) 6 Cl.2H 2 O showing a mass loss of 2.57% below 150 ºC, corresponding to the removal of the one water molecule from the channels (calc 2.54%), and a total observed mass loss of 17.02% (16.59%) by 1000 ºC leaving a residue of Yb 2 O 3. S5

6 %T cm-1 Figure S3 FTIR spectrum of Yb 3 O(OH) 6 Cl.2H 2 O. S6

7 Figure S4 Powder XRD patterns showing the structural evolution of Yb 3 O(OH) 6 Cl.2H 2 O between room temperature and 550 ºC. The impurity phase (reflections at 10.2, 17.7 and 27.1 º2θ) shows a greater thermal stability in comparison to Yb 3 O(OH) 6 Cl.2H 2 O decomposing at approximately 350 ºC which could be indicative of a layered Yb hydroxide phase. S7

8 Figure S5 Comparison of the powder XRD patterns of Yb 3 O(OH) 6 Cl.2H 2 O (green) and Lu 3 O(OH) 6 Cl.2H 2 O (red). S8

9 Anion Exchange Derivatives Absolute Intensity Figure S6 Powder XRD patterns for (a) Yb 3 O(OH) 6 Cl.2H 2 O (dark blue) (b) Yb 3 O(OH) 6 (CO 3 ) 0.5.H 2 O (purple) (c) Yb 3 O(OH) 6 (C 4 H 4 O 4 ) 0.5.H 2 O (light blue)and (d) Yb 3 O(OH) 6 (C 2 O 4 ) 0.5.H 2 O (green) 2Theta (d) (c) (b) (a) (a) %T (b) (c) (d) cm-1 Figure S7 FTIR spectra for (a) Yb 3 O(OH) 6 Cl.2H 2 O (black) (b) Yb 3 O(OH) 6 (CO 3 ) 0.5.H 2 O (blue) (c) Yb 3 O(OH) 6 (C 4 H 4 O 4 ) 0.5.H 2 O (red)and (d) Yb 3 O(OH) 6 (C 2 O 4 ) 0.5.H 2 O (green) S9

10 Sample Weight (%) Temperature (ºC) Figure S8 TGA trace for Yb 3 O(OH) 6 (C 4 H 4 O 4 ) 0.5.H 2 O showing a total mass loss of 1.80 (calc. 2.53) % below 200 ºC corresponding to the removal of water and a total mass loss of (17.12) % by 1000 ºC % Mass Temperature (ºC) Figure S9 TGA trace for Yb 3 O(OH) 6 (C 2 O 4 ) 0.5.3H 2 O showing a total mass loss of (calc 19.60) % below 900 ºC. S10

11 Sample Weight (%) Temperature (ºC) Figure S10 TGA trace for Yb 3 O(OH) 6 (CO 3 ) 0.5.2H 2 O showing a total mass loss of 4.81 (calc. 5.13) % below 200 ºC corresponding to the removal of water and a total mass loss of (25.94) % by 1000 ºC. S11

12 (a) (b) (c) (d) Figure S11 SEM images of (a)-(b)yb3o(oh)6cl.2h2o, (c) Yb3O(OH)6(CO3)0.5.2H2O and (d) Yb3O(OH)6(C2O4)0.5.3H2O S12