title: Organic-inorganic hybrid supermicroporous iron(III) phosphonate nanoparticles as an efficient catalyst for the synthesis of biofuels.
abstract: Here we report a novel family of crystalline, supermicroporous iron(III) phosphonate nanomaterials (HFeP-1-3, HFeP-1-2, and HFeP-1-4) with different Fe(III)-to-organophosphonate ligand mole ratios. The materials were synthesized by using a hydrothermal reaction between benzene-1,3,5-triphosphonic acid and iron(III) chloride under acidic conditions (pH ≈ 4.0). Powder X-ray diffraction, N2 sorption, transmission and scanning electron microscopy (TEM and SEM) image analysis, thermogravimetric and differential thermal analysis (TGA-DTA), and FTIR spectroscopic tools were used to characterize the materials. The triclinic crystal phase [P1(2) space group] of the hybrid iron phosphonate was established by a Rietveld refinement of the PXRD analysis of HFeP-1-3 by using the MAUD program. The unit cell parameters are a = 8.749(1), b = 8.578(1), c = 17.725(3) Å; α = 104.47(3), β = 97.64(1), γ = 113.56(3)°; and V = 1013.41 Å(3). With these crystal parameters, we proposed an 24-membered-ring open framework structure for HFeP-1. Compound HFeP-1-3, with an starting Fe/ligand molar ratio of 3.0, shows the highest Brunauer-Emmett-Telller (BET) surface area of 556 m(2) g(-1) and uniform supermicropores of approximately 1.1 nm. The acidic surface of the porous iron(III) phosphonate nanoparticles was used in a highly efficient and recyclable catalytic transesterification reaction for the synthesis of biofuels under mild reaction conditions.
authors: Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, 700 032, India.
authors: Malay
authors: M
authors: Pramanik
authors: Asim
authors: A
authors: Bhaumik
mesh_terms: D056804:Biofuels; D002384:Catalysis; D002712:Chlorides / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004951:Esterification; D005290:Ferric Compounds / Q000737:chemistry*; D008968:Molecular Conformation; D053758:Nanoparticles / Q000737:chemistry*; D063065:Organophosphonates / Q000737:chemistry*; D016062:Porosity
chemical_list: D056804:Biofuels; D002712:Chlorides; D005290:Ferric Compounds; D063065:Organophosphonates; C024555:ferric chloride