Oxidation of dodecanoate intercalated iron(II)–iron(III) layered double hydroxide to form 2D iron(III) (hydr)oxide layers

TY - JOUR

T1 - Oxidation of dodecanoate intercalated iron(II)–iron(III) layered double hydroxide to form 2D iron(III) (hydr)oxide layers

AU - Huang, Lizhi

AU - Ayala Luis, Karina Barbara

AU - Fang, Liping

AU - Dalby, Kim Nicole

AU - Kasama, Takeshi

AU - Bender Koch, Christian

AU - Hansen, Hans Chr. Bruun

PY - 2013/11

Y1 - 2013/11

N2 - A planar trioctahedral iron(II)-iron(III) hydroxide (green rust, GR) intercalated with dodecanoate (GRC12) has been oxidized by dioxygen to produce the corresponding planar iron(III) (hydr)oxide. The formulae of GRC12 and the final iron(III) product (oxGRC12) were determined to be FeII2.00FeIII 1.00(OH)5.31(C12H23O 2)0.66(SO4)0.51 and Fe III3O2.18(OH)3.13(C 12H23O2)0.56(SO4) 0.47, respectively. oxGRC12 has the same planar layer structure as GRC12, as revealed by identical powder X-ray diffraction patterns. The electrostatic interactions between the interlayer dodecanoate (C12) anions and the iron hydroxide planar layer were preserved during the oxidation, as shown by FTIR spectroscopy. The high positive charge in the hydroxide layer produced by the oxidation of iron(II) to iron(III) is partially compensated by the deprotonation of hydroxy groups, as shown by X-ray photoelectron spectroscopy. The Mössbauer quadrupole splitting of the iron(III) doublet increased on oxidation of GRC12, which has been attributed to the distortion of the octahedral sites caused by deprotonation and changes in the coordination site geometry. oxGRC12 is stable in air for more than 2 years. The van der Waals interactions between the alkyl chains of the intercalated dodecanoate anions play a crucial role in stabilizing the structure and hindering the collapse of the iron(II)-iron(III) (hydr)oxide structure during oxidation. This is the first report describing the formation of a stable planar layered octahedral iron(III) (hydr)oxide. oxGRC12 shows promise as a sorbent and host for hydrophobic reagents, and as a possible source of single planar layers of iron(III) (hydr)oxide. The formation of a planar trioctahedral iron(III) (hydr)oxide with a brucite-type structure is reported. It was formed by the solid-state oxidation of iron(II)-iron(III) layered double hydroxide precursors with a stable dodecanoate interlayer held together by van der Waals forces to keep the planar structure intact during oxidation.

AB - A planar trioctahedral iron(II)-iron(III) hydroxide (green rust, GR) intercalated with dodecanoate (GRC12) has been oxidized by dioxygen to produce the corresponding planar iron(III) (hydr)oxide. The formulae of GRC12 and the final iron(III) product (oxGRC12) were determined to be FeII2.00FeIII 1.00(OH)5.31(C12H23O 2)0.66(SO4)0.51 and Fe III3O2.18(OH)3.13(C 12H23O2)0.56(SO4) 0.47, respectively. oxGRC12 has the same planar layer structure as GRC12, as revealed by identical powder X-ray diffraction patterns. The electrostatic interactions between the interlayer dodecanoate (C12) anions and the iron hydroxide planar layer were preserved during the oxidation, as shown by FTIR spectroscopy. The high positive charge in the hydroxide layer produced by the oxidation of iron(II) to iron(III) is partially compensated by the deprotonation of hydroxy groups, as shown by X-ray photoelectron spectroscopy. The Mössbauer quadrupole splitting of the iron(III) doublet increased on oxidation of GRC12, which has been attributed to the distortion of the octahedral sites caused by deprotonation and changes in the coordination site geometry. oxGRC12 is stable in air for more than 2 years. The van der Waals interactions between the alkyl chains of the intercalated dodecanoate anions play a crucial role in stabilizing the structure and hindering the collapse of the iron(II)-iron(III) (hydr)oxide structure during oxidation. This is the first report describing the formation of a stable planar layered octahedral iron(III) (hydr)oxide. oxGRC12 shows promise as a sorbent and host for hydrophobic reagents, and as a possible source of single planar layers of iron(III) (hydr)oxide. The formation of a planar trioctahedral iron(III) (hydr)oxide with a brucite-type structure is reported. It was formed by the solid-state oxidation of iron(II)-iron(III) layered double hydroxide precursors with a stable dodecanoate interlayer held together by van der Waals forces to keep the planar structure intact during oxidation.

U2 - 10.1002/ejic.201300735

DO - 10.1002/ejic.201300735

M3 - Journal article

SN - 1434-1948

VL - 2013

SP - 5718

EP - 5727

JO - European Journal of Inorganic Chemistry

JF - European Journal of Inorganic Chemistry

IS - 33

ER -