Dr. Christian SERRE

Thèmes de recherche développés

Synthesis and structure of porous hybrid solids

Synthesis and characterization of porous hybrid solids based on transition metals (Fe, Cr, V)
(collaboration P. Horcajada (Fe), T. Devic (V) (Versailles); N. Stock (Kiel, Germany))

This concerns the development of new synthetic routes of MOFs based on trivalent transition metals with a particular interest for iron, a non toxic, cheap and redox active cation. A route based on trimeric oxocentered SBUs has been set-up, [1] leading either to very large pores rigid solids MIL-100 and -101 [2 3] with huge pore volumes and surface areas or the highly flexible MIL-88A-D compounds [4] with breathing amplitudes between 85 and 230 % (figure 1).

Figure 1: (left) view of the crystal structures of MIL-100/101(left); (right) the breathing phenomena in MIL-88.

Synthesis and characterization of porous hybrid solids based on tetravalent transition metals (Ti, Zr)
(collaboration T. Devic (Zr) (Versailles), S. Gross (Zr) (Padova, Italy), K.P. Lillerud (Zr) (Oslo, Norway); C. Sanchez, L. Rozes (Ti) (Paris))

There is still a high interest in the development of new porous hybrid solids based on titanium(IV) or zirconium, which are non toxic elements interesting for many applications. A higher chemical stability of the resulting MOFs is also expected with these higher valence metals. A nice example concerns the porous titanium diphosphonate MIL-91(Ti) built up from corner sharing chains of titanium octahedral and piperazinediphosphonate moieties (figure 2).[5] Its structure exhibits a small permanent porosity (4 Angst.) and an accessible pore volume for gases (SBET=350 m2.g-1). Current work concerns the discovery of new Ti or Zr based MOFs, using new SBU approaches, with increased porosity.

Figure 2 : view of the crystal structures of MIL-91(Ti) along the c axis.

Functionalization of MOFs
(Collaboration: T. Devic, P. Horcajada, O. David and E. Magnier (Versailles); N. Stock (Kiel, Germany); J. S. Chang (Korea))

In order to modulate the adsorption or catalytic properties, we have started to implement new strategies to functionalize our porous solids.[6, 7] Two approaches have been followed: either introducing prior to the synthesis an organic functional group directly by replacement of a proton of the aromatic ring by a polar or apolar group (Cl, NH2, CH3…) to produce an isostructural MOF with functionality within its framework, or post-synthesis grafting of amino groups on the accessible Lewis Metal sites (figure 3).

Figure 3: (top) organically modified carboxylate linkers; (down) schematic view of the post-synthesis grafting of amines on a supertetrahedron of MIL-101.

Characterization

To determine the structures of new solids, computer simulation (G. Maurin (Montpellier)) is used in order to decrease the time consuming process of the structure determination. X-Ray powder diffraction data on the dried solids are collected by Dr. N. Audebrand (Rennes) while high resolution X-Ray diffractions patterns are often collected at the ESRF (SNBL (Y. Filinchuk), ID31 (I. Margiolaki)) or Soleil (Cristal, E. Elkaim). The physical properties of the MOFs are often analyzed by spectroscopy (IR, Raman, UV) by A. Vimont and M. Daturi (Caen) or by Solid State NMR (F. Taulelle). The iron solids are also analyzed on a regular basis by Mossbauer spectroscopy (J.M. Grenèche, Le Mans).

Applications of MOFs

Bioapplications
(Collaboration : P. Horcajada (Versailles); R. Gref, P. Couvreur (Chatenay); R. Morris (St Andrews, UK); G. Maurin (Montpellier); R. Denoyel and O. Schäf (Marseille))

We were the first to use porous hybrid solids for drug delivery, with the controlled release of Ibuprofen using the large pores hybrid solids MIL-100 and MIL-101 or the flexible compound MIL-53, leading either to a record drug loading capacity of 1.4g of drug per g of dried solid or a very slow release up to three weeks (figure 4). [8, 9] This was the starting point of a new field of research, i.e. the use of porous cristallized hybrid solids for several bioapplications including drug delivery, adsorption of toxins, biological gases and so on… The European community has considered this approach as highly valuable since a European Research Council FP7 starting researcher grant has been awarded for 2008-2013 to develop the understanding of biomolecules-MOFs interactions.

Figure 4: kinetics of Ibuprofen release (SBF, 37°C) of different porous materials.

Adsorption, separation of fluids
(Collaboration: T. Devic, P. Horcajada and F. Millange (Versailles); S. Bourrelly, P.L. Llewellyn (Marseille); M. Latroche (Thiais); G. de Weireld (Mons); J.S. Chang (Korea); A. Rodrigues (Porto); P. Trens and G. Maurin (Montpellier); H. Jobic (Lyon); A. Vimont and M. Daturi (Caen))

MOFs are promising candidates for gas storage (hydrogen, methane) or the capture of gases (or vapors) such as CO2. [10, 11] Three types of solids have been evaluated: flexible MOFs which exhibit steps in their adsorption isotherms, MOFs with metal sites that possess a high affinity useful to increase the selectivity and finally large pore hybrid solids which have huge sorption capacity. Our work consists in making purified samples for adsorption or separation tests as well as studying the influence of the breathing character upon adsorption of guests. [12, 13]

Figure 5: left : hydrogen adsorption isotherms of MIL-101a (as-synthesised; b : activated) (77 K and 298 K); right : CO2 adsorption isotherm of MIL-53(Cr) (303 K).

NanoChemistry
(collaboration: P. Horcajada and O. David (Versailles); R. Gref and P. Couvreur (Chatenay) ; J.S. Chang (Korea); D. Grosso, C. Boissière, C. Sanchez (Paris))

The use of MOFs for some practical applications (drug delivery, thin films) requires the synthesis of nanoparticles with a controlled particle size as well as a narrow pore size distribution. In addition, the surface of the particles has to be modified with surface agents (polymers…) in order both to control the growth and avoid agglomeration but also to provide furtivity and addressing properties to the particles. The synthesis of nanoMOFs is currently done either by traditional solvothermal synthesis or by the use of microwave irradiation (figure 6). [14, 15]

Figure 6: nanoparticles obtained by microwave synthesis (left : MIL-101(Fe); right : MIL-101(Cr)).

Other applications

The catalytic properties of our MOFs have been to date analyzed by the group of Dr. J.S. Chang (Krict, Korea). MOFs with Lewis acidity have been tested for oxidation reactions or for basic catalysis through the grafting of amines.[16, 6] Insertion of polyanionic species (Keggin…) within the large pores MIL-100 and MIL-101 solids, performed by Dr. C. Roch (Versailles), will also lead soon to new catalytic properties.
The lithium insertion properties of iron MOFs are currently evaluated by the group of J.M. Tarascon and M. Morcrette (Amiens). The proof of principle of the use of MOFs as new battery materials has been demonstrated with the porous flexible iron carboxylate MIL-53(Fe). [17]

References

[1] A route to the synthesis of trivalent transition metals porous carboxylates with trimeric secondary building units.., Serre, C.; Millange, F.; Surblé, S.; Férey, G., Angew. Chem. Int. Ed 2004, 43, 6286-6289
[2] A hybrid solid with giant pores prepared by combination of targeted chemistry, simulation and powder diffraction. Férey, G.; Serre, C.; Mellot-Draznieks, C.; Millange, F.; Surblé, S.; Dutour, J.; Margiolaki, I., Angew. Chem. Int. Ed., 2004, 43, 6296-6301
[3] A chromium terephthalate-based solid with unusually large pore volumes and surface area. Férey, G.; Mellot-Draznieks, C.; Serre, C.; Millange, F.; Dutour, J.; Surblé, S.; Margiolaki, I. Science, 2005, 309, 2040-2042
[4] The role of solvent-host interactions that lead to very large swelling of hybrid frameworks. C. SERRE C. MELLOT-DRAZNIEKS, S. SURBLE, N. AUDEBRAND, Y. FILINCHUK & G. FEREY, Science. 2007, 315, 1828-1831
[5] Synthesis, structure and properties of related microporous N,N’-piperazinebismethylenephosphonates of aluminium and titanium; C. Serre, J. A. Groves, P. Lightfoot, A. M. Z. Slawin, P. A. Wright, N. Stock, T. Bein, M. Haouas, F. Taulelle, and G. Férey: Chem. Mater. 2006 18, 1451-1457:
[6] High-throughput rationalization of the formation of metal organic frameworks in the iron(III) aminoterephtalate solvothermal system. S. BAUER, C. SERRE, T. DEVIC, P. HORCAJADA, J. MARROT, G. FEREY & N. STOCK. Inorg. Chem. 2008, 47, 7568-7676
[7] Y. K. Hwang, D.-Y. Hong, J. S. Chang, S. H. Jhung, Y.-K. Seo, J. Kim, A. Vimont, M. Daturi, C. Serre, and G. Férey, Angew. Chem. Int. Ed, 47, 2008, 4144
[8] Metal-organic frameworks as new materials for drug delivery. Horcajada, P.; Serre, C.; Vallet-Regi, M.; Sebban, M.; Taulelle, F.; Férey, G., Angew. Chem. Int. Ed., 2006, 45, 5974-5978
[9] P. Horcajada, C. Serre, G. Maurin, N. A. Ramsahye, M. Vallet-Regí, M. Sebban, F. Taulelle, and G. Férey J. Am. Chem. Soc., 130, 2008, 6774
[10] Hydrogen storage in the giant pores of Metal-organic frameworks MIL-100 and MIL-101. M. LATROCHE, S. SURBLE, C. SERRE, C. MELLOT-DRAZNIEKS, P.L. LLEWELLYN, J.S. CHANG, S.H. JHUNG & G. FEREY, Angew. Chem. Int. Ed.. 2006, 45, 8227-8231
[11] An explanation for the very large breathing effect of a metal-organic framework during CO2 adsorption. C. SERRE, S. BOURRELLY, A. VIMONT, N. A. RAMSAHYE, G. MAURIN, P. LLEWELLYN, M. DATURI, Y. FILINCHUK, O. LEYNAUD, P. BARNES & G. FÉREY, Adv. Mater. 2007, 19, 2246-2251
[12] Structural effects of the nature of solvents on the breathing of MOFs : an in situ diffraction study. F. MILLANGE, C. SERRE, N. GUILLOU, G. FEREY & R.I. WALTON. Angew. Chem. Int. Ed. 2008, 47, 4100-4105
[13] Experimental evidence supported by simulations of the hydrogen super-mobility in metal-organic frameworks materials.
F. SALLES, H. JOBIC, G. MAURIN, M.M. KOZA, T. DEVIC, C. SERRE, G. FEREY. Phys. Rev. Lett. 2008, 100, 245901, 1-4
[14] Facile Synthesis of the Chromium Terephthalate MIL-101 with Giant Pores and Its Sorption Ability for Benzene; Sung Hwa Jhung, Jin-Ho Lee, Ji Woong Yoon, Christian Serre, Gérard Férey and Jong-San Chang Adv. Mater (2006), 19(1), 121-124.
[15] Colloidal route towards Optical thin films of Nanoporous Metal-Organic-Frameworks; P. Horcajada, C. Serre, D. Grosso, C. Boissière, S. Perruchas, C. Sanchez and G. Férey Adv. Mater., 2008, in press
[16] Synthesis and catalytic properties of MIL-100(Fe), an iron(III) carboxylate with large pores. P. HORCAJADA, S. SURBLE, C. SERRE, D-Y HONG, Y-K SEO, J-S CHANG, J-M GRENECHE, I. MARGIOLAKI & G. FEREY, Chem. Comm. 2007, 2820-2822
[17] Mixed valence Li/Fe-based MOFs with both reversible redox and sorption properties. G. FEREY, F. MILLANGE, M. MORCRETTE, C. SERRE, M.L. DOUBLET, J.M. GRENECHE & J.M. TARASCON, Angew. Chem. Int. Ed.. 2007, 46, 3259-3263