2. 2 4 3 1 Work schedule Formation mechanism Preparation of ZSM-5 zeolite films on oxide coated stainless steel substrates (SiO 2, Al 2 O 3, TiO 2, ZrO 2 ) Effect of surface roughness on b-oriented ZSM-5 zeolite films

3. 1 Effect of surface roughness on b-oriented ZSM-5 zeolite films 0.32TPAOH:1TEOS:165H 2 O 165 ℃ crystallized for 24 h Surface roughness was decreased > > 0.32TPAOH:1TEOS:165H 2 O:0.01Al(NO 3 ) 3 Stirring at room temperature for 24 h 1. Yan et al, Chem Mater, 2001, 13, 1101-1107 stainless steel tube air-calcined stainless steeluntreated stainless steel

4. Figure 1. Top-view SEM images of ZSM-5 films on stainless steel tube (A), air-calcined stainless steel chip (B), untreated stainless steel (C) and XRD patterns of the zeolite layer on air-calcined and untreated stainless steel chips. A. On stainless steel tubeB. On air-calcined stainless steel chip C. On untreated stainless steel D

5. Preparation of ZSM-5 zeolite films on oxide coated stainless steel substrates (SiO 2, Al 2 O 3, TiO 2, ZrO 2 ) Al 2 O 3, SiO 2, TiO 2, ZrO 2 b-oriented ZSM-5 membrane 2 Rough surface Oxide surfaces Zeolite films

6. Figure 4. Top-view SEM image of stainless steel supported Al 2 O 3 layer. Al 2 O 3 layer Figure 6. Top-view SEM image of stainless steel supported ZrO 2 layer. ZrO 2 layer Figure 5. Top-view SEM image of stainless steel supported TiO 2 layer. TiO 2 layer 1 2 3 Figure 2. Drying and calcination profiles of coatings. 0.5 ℃ /min 450 ℃ calcination drying 4 Figure 3. Top-view SEM image of stainless steel supported SiO 2 layer. SiO 2 layer 5 Dip coating procedure

7. Figure 7. Top-view SEM images of ZSM-5 films on stainless steel supported SiO 2 (A), Al 2 O 3 (B), TiO 2 (C), ZrO 2 (D) layers. The insert in (C ) is a cross-sectional SEM view of ZSM-5 film on TiO 2 - coated substrate. B. Al 2 O 3 coated D. ZrO 2 coated A. SiO 2 coated C. TiO 2 coated

8. OH hydrophilic property F(D)= - A R/6D 2 2R D Van der waals forceZeta potential Discussion

9. OH Figure 8. Zeta potential of SiO 2 /Al 2 O 3 /TiO 2 /ZrO 2 in aqueous suspension F(D)= - AR/6D 2 2R D Zeta potential do not affect the growth of zeolite films very much. Zeta potential

10. F(D)= - AR/6D 2 2R D Figure 9. contact angles of synthesis solution on the SiO 2 (A), Al 2 O 3 (B), TiO 2 (C), ZrO 2 (D) sublayer. OH For different oxide surfaces, the hydrophilic property of the sublayer is not the main factor affecting the morphology of the zeolite film. hydrophilic property

11. F(D)= - AR/6D 2 2R D OH For the same oxide surface, different hydrophilic property of the surface may cause different morphology of zeolite films. hydrophilic property 3. M J M Mies, Journal of Catalysis 247 (2007) 328–338. 2. Annemieke W C van den Berg, Microporous and Mesoporous Materials 66 (2003) 303–309. Increase zeolite nucleation Before UV after UV TiO 2 Figure 10. relationship of the UV irradiation time and the static contact angles of synthesis solution on TiO 2 coated stainless steel. UV

12. F(D)= - A R/6D 2 OH The Hamaker constant is given by 4 : A = π 2 Cρ 1 ρ 2 The value of A can be estimated through the Lifshitz theory of macroscopic van der waals interactions(McLachlan’s Equation) 4. Hamaker constant from McLachlan’s Equation Where, “1” and “2” denote two interacting bodies inside medium “3”; K: Boltzmann constants(J/K) T: temperature (K) ε: dielectric constant n: refractive indices h: Planck's constant (J·s) ν e : absorption frequency(Hz) 4. J N Israelachivili, Intermolecular and Surface Forces, 2 nd edn., Academic Press, San Diego,1992. 2R D Waals force [1]

13. SiO 2 Al 2 O 3 ZrO 2 TiO 2 Table 1. Hamaker constants A v>0 (10 -20 ) for two media interacting across water a 0.37 1.24 2.21 3.16 SiO 2 a Estimated from the expression and constants in Ref. [4] Similar findings were reported in a study on the growth of ZSM-5 films on alumina and other surfaces [5]. Calculated results: SiO 2 Al 2 O 3 ZrO 2 SiO 2 Al 2 O 3 0.35 1.2 4.1 2.1 7.3 [5] Re Lai, Microporous and Mesoporous Materials 37 (2000) 9–19. Table 2. Hamaker constants A v>0 (10 -20 ) for two media interacting across water OH F(D)= - A R/6D 2 2R D Waals force

14. Synthesis condition 0.32TPAOH ： 1TEOS ： 165H 2 O ： 0.01Al(NO 3 ) 3 Aging time < 24 h Crystallized at 165 o C for 24 h. Surface roughness palys an important role in crystal orientation and coverage of the zeolite films. For the same oxide surface, the hydrophilicity of the surface is also important because hydroxyl group may increase zeolite nucleation. For different oxide surfaces, van der Waals force between the silica bodies and the surface wall is one the most important factors in growing a continuous oriented film. 2R D summary OH

15. 3 Formation mechanism Silica gel bodies TPA + (SiO 2 ) m

16. Zeolites,1997,19(4): 262-269. This model can explain well the fact that b-oriented crystals are formed on both horizontally and vertically placed substrates. But it is difficult to use this model to explain why a-oriented crystals appear in the film. It also has difficulty in explaining the presence of a secondary layer under certain conditions. Figure 11. A Si-ZSM-5 thin film growth model on a support in three steps.

17. Explain why a-oriented crystals appear in the film sometimes! Explain why a secondary layer appeared under certain conditions! why random crystals appeared in the film when different synthesis solution used? Figure 12. A schematic drawing of a possible formation mechanism for b-oriented zeolite MFI thin film. Microporous and Mesoporous Materials, 48(2001) 229-238

18. Chinese Science Bulletin, 55(2010),27-28 A gel layer enriched with TPA and TS-1 precursor was first formed on the chitosan surface, followed by the nucleation within the gel-layer, especially on the chitosan surface. nucleation Figure 13. Schematic drawing of the formation mechanism for b-oriented TS-1 zeolite film on the porous solid supported chitosan surface.

19. substrate Silica gel bodies TPA + Gel layer Zeolite crystal b-oriented zeolite film Figure 14. A schematic drawing of a possible formation mechanism for b-oriented zeolite MFI thin film.

20. Glass substrate TiO 2 coating ZSM-5 zeolite Rough surface Figure 15. Top-view SEM images of ZSM-5 films on stainless steel tube(A) and glass(B) coated with TiO 2 layer. A. stainless steel tubeB. glass

21. 4 Work schedule Paper writing Functional modification of substrates