Supporting Information. Effective Formaldehyde Capture by Green Cyclodextrin Based. Metal-Organic Framework

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1 Supporting Information Effective Formaldehyde Capture by Green Cyclodextrin Based Metal-Organic Framework Lu Wang, a,c Xiang-Yong Liang, a,c Zhi-YiChang, a,c Li-Sheng Ding, a Sheng Zhang *b and Bang-Jing Li *a a. Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, , China. b. State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University Sichuan University, Chengdu, , China. c. University of Chinese Academy of Sciences, Beijing, , China. Corresponding authors: libj@cib.ac.cn, zslbj@163.com S-1

2 I. Materials, instruments and methods γ-cyclodextrin (γ-cd) was purchased from J&K (Beijing, China); Potassium hydroxide (KOH), methyl alcohol and formaldehyde(hcoh) were produced by Chengdu Kelong chemical engineering company (Chengdu, China). Scanning electron microscope(sem) was measured by Phenom pro, Phenom-world BV. Formaldehyde concentration was monitored by portable formaldehyde meter. X-Ray Powder Diffraction(XRD) was collected by PANalytical B.V. Low-pressure gas adsorption experiments were performed on a Quantachrome AUTOSORB-1 automatic volumetric instrument. The UV/Vis and fluorescence spectra results were detected using Varioskan Flash (Thermo, USA).The thermogravimetric analysis (TGA) was characterized using Thermal Analyzer EXSTAR 6000 (Seiko Instruments Inc, Japan). 1. Synthesis of CD-MOFs 1 γ-cd (1.30 g, 1 mmol) and KOH (0.45 g, 8 mmol) were dissolved into 20 ml pure water. The aqueous solution was filtered and MeOH was allowed to vapor diffuse into the solution. After 3-7 days, white cubic crystals which were appeared at the bottom of the vessel, were isolated, filtered and washed with MeOH for three times. In order to remove interstitial solvent, the γ-cd-mof-k was immersed in CH 2 Cl 2 for three days and the CH 2 Cl 2 was refreshed three times. The wet sample was then dried in vacuum ovenat room temperature for 10 h, and then at 45 0 C for 12 h. The white power was γ-cd-mof-k. The method of preparing α-cd-mof-k, β-cd-mof-k is the same as γ-cd-mof-k. 2. The research of formaldehyde adsorption behavior of CD-MOFs CD-MOFs were put into vacuum-tight container and the formaldehyde solution (the concentration was 0.3%)was added. Then, electrical heater was used to heat formaldehyde solution and formaldehyde solution could be turned to formaldehyde gas. Portable formaldehyde meter was monitored the changes of formaldehyde concentration at 293 K and 1 atm. The adsorption behavior of formaldehyde at different temperature was tested at 1 atm.the setup was S-2

3 shown in Figure S1. 3. The adsorption behavior of benzene, phenylethylene, HCl and SO 2 1 atm The research method was similar to the above method. The test condition was at 293 K and 4. Synthesis of ZIF-8 2 Zn(NO 3 ) 2 6H 2 O (2.933 g, 9.87 mmol) was dissolved in 200 ml of methanol and 2-methylimidazole was also dissolved in 200 ml of methanol. The two kinds of solution were rapidly poured together under stirring with a magnetic bar. After 1 hour, the crystal was separated from solution by centrifugation and washing with fresh methanol. The white powder was the ZIF-8. The XRD patterns of ZIF-8 was showed in Figure S Synthesis of UiO-66-OH 3 2-Hydroxyterephthalicacid (0.175mmol), ZrCl 4 (0.175mmol, 41mg), and DMF(4mL) was heated at 120 o C for 24h.The solid was then isolated by centrifugation and washed with DMF(10mL)for three times. After washing, the solids were centrifuged and dried under vacuum. 6. Adsorption isotherms 6.1 Langmuir isotherm 4 The Langmuir adsorption, which is the monolayer adsorption, depends on the assumption that the intermolecular forces decrease rapidly with distance, and consequently predicts the existence of monolayer coverage of the adsorbate at the outer surface of the adsorbent. The Langmuir equation was calculated as follows: C e q e = 1 K L q max + C e q max Where q e is the equilibrium ormaldehyde concentration on the adsorbent (mg/g), C e is the equilibrium formaldehyde concentration in container (mg/m 3 ), q max is the capacity of the adsorbent (mg/g), and K L is the Langmuir adsorption constant (m 3 /mg). Thus, a plot of C e /q e vs C e gives a straight line. The slope is 1/q max and the intercept is 1/ (q max K L ). 6.2 Freundlich isotherm 5 The Freundlich equation is an empirical equation employed to describe heterogeneous systems. The related equation is listed as follows: lnq e = lnk F + 1 n lnc e S-3

4 where q e is the equilibrium formaldehyde concentration on adsorbent (mg/g), C e is the equilibrium formaldehyde concentration in container (mg/m 3 ), K F is Freundlich constant (m 3 / g), and 1/n is the heterogeneity factor. Therefore, a plot of lnc e vs lnq e gives a straight line. The slope is 1/n and the intercept is lnk F. 7. Thermodynamic studies 6,7 The thermodynamic parameters included in standard free energy (ΔG 0 ), enthalpy (ΔH 0 ), and entropy (ΔS 0 ). The thermodynamic equations were determined by using the following equations K C = C A C S ΔG 0 = RT ln K C, ln K C = ΔS0 R - ΔH0 RT In order to confirm that the kinetic data was fitted with the second-order model, the ΔH 0 and ΔS 0 was calculated by the following equations: lnk=lna-e a /RT ΔH 0 = E a RT ΔS 0 = (ΔH 0 ΔG 0 )/T where K is the rate constant of sorption and Ea is the Arrhenius activation energy of sorption. When ln k is plotted versus 1/T (Figure S18), a straight line with slope E a /R is obtained. Then, the ΔH 0 and ΔS 0 was listed in Table S3. 8. Kinetic modeling 7.1 Pseudo-first-order kinetic model is as the following equation 8 : dq t dt = K 1 (q e - q t ) log (q e q t ) = logq e - K t where q e is the amount of formaldehyde at equilibrium time in container (mg/m 3 ), q t is the amount of formaldehyde at any time. K 1 is the equilibrium rate constant. 7.2 Pseudo-second order kinetic model is as the following equation 9 : dq t d t = K 2 (q e -q t ) 2 t q t = 1 K 2 q e 2 + t q e S-4

5 Where q e is the amount of formaldehyde at equilibrium time in container (mg/m 3 ), q t is the amount of formaldehyde at any time. K 2 is the equilibrium rate constant. II.Characteristic of materials Figure S1. The test equipment chart of formaldehyde adsorption Figure S2. (a) SEM image of α-cd-mof-k. (b) XRD patterns of α-cd and α-cd-mof-k. Figure S3. (a) SEM image of β-cd-mof-k. (b) XRD patterns of β-cd and β-cd-mof-k. S-5

6 Figure S4. (a) SEM image of γ-cd-mof-k. (b) XRD patterns of γ-cd and γ-cd-mof-k. Figure S5. The TGA curves of γ-cd and γ-cd-mof-k. Figure S6. (a) N 2 sorption isotherms at 77K of γ-cd. (b) Pore size distributions of γ-cd analyzed with Horváth-Kawazoe (HK) method from N 2 adsorption isotherms at 77 K. S-6

7 Figure S7. (a) N 2 sorption isotherms at 77K of γ-cd-mof-k. (b) Pore size distributions of γ-cd-mof-k analyzed with Horváth-Kawazoe (HK) method from N 2 adsorption isotherms at 77 K. Figure S8. (a) SEM image of γ-cd-mof-k after adsorption. (b) XRD patterns of γ-cd-mof-k before and after adsorption. Figure S9. The corresponding absorption curves of γ-cd at different relevant temperatures. S-7

8 Figure S10. (a) SEM image of γ-cd-mof-cs. (b) XRD patterns of γ-cd-mof-cs. Figure S11. Powder X-ray diffraction patterns for α-cd-mof-k 10. Figure S12.Powder X-ray diffraction patterns for β-cd-mof-k 11. S-8

9 Figure S13. Powder X-ray diffraction patterns for evacuated (activated) and as-synthesized samples of γ-cd-mof-k. 1 Figure S14. IR of CD-MOFs. Figure S15. XPS of CD-MOFs S-9

10 Figure S16. XRD patterns of ZIF-8 Figure S17. XRD patterns of UiO-66-OH Figure S18.Arrhenius plots of HCHO-γ-CD-MOF-K. S-10

11 Figure S19. Adsorption curves of γ-cd-mof-k at different concentrations of HCHO. Table S2 Information for BET consistency criteria. γ-cd-mof-k P/P 0 range R Slope C Q m BET surface area m 2 /g Adsorption average pore diameter 0.775nm Table S3. The thermodynamic parameters calculated by second-order model. materials T (K) ΔG 0 (kj/mol) ΔH 0 (kj/mol) ΔS 0 (kj/mol) γ-cd-mof-k References 1. Smaldone, R. A.; Forgan, R. S.; Furukawa, H.; Gassensmith, J. J.; Slawin, A. M.; Yaghi, O. M.; Stoddart, J. F.Metal Organic Frameworks from Edible Natural ProductsAngew. Chem. Int. Ed. 2010, 49, Cravillon, J.; Münzer, S.; Lohmeier, S. J.; Feldhoff, A.; Huber, K.; Wiebcke, M. Rapid Room-Temperature Synthesis and Characterization of Nanocrystals of a Prototypical Zeolitic Imidazolate Framework Chem. Mater. 2009, 21, S-11

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