Search NASA⌕ Search

SEARCH · Search NASA

Results for “Co(IO3)2”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

7 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Co(IO3)2 by Materials Project

Co(IO3)2 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is three-dimensional. Co2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Co–O bond distances ranging from 2.11–2.71 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Co2+ and three I5+ atoms. There are a spread of O–I bond distances ranging from 1.88–2.75 Å. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Co2+ and two I5+ atoms. There are one shorter (1.86 Å) and one longer (2.61 Å) O–I bond lengths. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Co2+ and two equivalent I5+ atoms. There are one shorter (1.84 Å) and one longer (2.59 Å) O–I bond lengths. In the fourth O2- site, O2- is bonded in a distorted water-like geometry to two equivalent Co2+ and one I5+ atom. The O–I bond length is 1.84 Å. In the fifth O2- site, O2- is bonded in a distorted water-like geometry to one Co2+ and two I5+ atoms. There are one shorter (1.86 Å) and one longer (2.64 Å) O–I bond lengths. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Co2+ and two equivalent I5+ atoms. There are one shorter (1.88 Å) and one longer (2.53 Å) O–I bond lengths. There are two inequivalent I5+ sites. In the first I5+ site, I5+ is bonded in a 6-coordinate geometry to six O2- atoms. In the second I5+ site, I5+ is bonded in a 6-coordinate geometry to six O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Co(IO3)2 by Materials Project

Co(IO3)2 is zeta iron carbide-derived structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with twelve equivalent IO6 octahedra. The corner-sharing octahedra tilt angles range from 50–53°. There are two shorter (2.11 Å) and four longer (2.24 Å) Co–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Co2+ and two equivalent I5+ atoms. Both O–I bond lengths are 2.17 Å. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Co2+ and two equivalent I5+ atoms. There are one shorter (2.10 Å) and one longer (2.14 Å) O–I bond lengths. I5+ is bonded to six O2- atoms to form IO6 octahedra that share corners with six equivalent CoO6 octahedra and edges with three equivalent IO6 octahedra. The corner-sharing octahedra tilt angles range from 50–53°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Co(IO3)2 by Materials Project

Co(IO3)2 is zeta iron carbide-derived structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with twelve equivalent IO6 octahedra. The corner-sharing octahedra tilt angles range from 48–56°. There are a spread of Co–O bond distances ranging from 2.00–2.35 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Co2+ and two equivalent I5+ atoms. There are one shorter (2.01 Å) and one longer (2.23 Å) O–I bond lengths. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Co2+ and two equivalent I5+ atoms. Both O–I bond lengths are 2.19 Å. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Co2+ and two equivalent I5+ atoms. There are one shorter (2.07 Å) and one longer (2.13 Å) O–I bond lengths. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Co2+ and two equivalent I5+ atoms. Both O–I bond lengths are 2.25 Å. I5+ is bonded to six O2- atoms to form IO6 octahedra that share corners with six equivalent CoO6 octahedra and edges with three equivalent IO6 octahedra. The corner-sharing octahedra tilt angles range from 48–56°.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Removal of iodine (I- and IO3-) from aqueous solutions using CoAl and NiAl layered double hydroxides

The treatment of radioactive iodine released from nuclear power plants and radiological waste disposal sites is of great concern due to its high mobility and toxicity. In particular, iodide (I-) and iodate (IO3-) are the major iodine species of concern under various pHs and groundwater conditions. Herein, CoAl and NiAl layered double hydroxides (LDHs) were synthesized by a hydrothermal method and investigated to identify the removal mechanisms and efficiencies of both I- and IO3-. Both CoAl and NiAl LDHs exhibited rapid iodine removal processes within 20 min, following the pseudo-second-order model via ion-exchange with parent NO3- anion in the LDHs. The CoAl LDH’s maximum sorption capacities for I- and IO3- were about 1.67 and 2.16 mmol g-1, respectively, whereas for the NiAl LDH, these were about 2.10 and 2.26 mmol g-1, and they followed the Langmuir isotherm model. Interestingly, both the CoAl and NiAl LDHs showed a preferential ion-exchange affinity for IO3- over I-, which was attributed to the structural similarity of the IO3- and NO3- as well as new formation of secondary Co(or Ni)(IO3)2·2H2O phases. In addition, a desorption study indicated that the selectivity order was SO42- = IO3- = OH- > HCO3- > Cl- > NO3- = I- and demonstrated the higher retention of the IO3- than I- anion. This study provides insights into promising iodine sorbents and the different removal mechanisms of I- and IO3- using CoAl and NiAl LDHs.

Kang, Jaehyuk↗
DOE OSTI2020

Materials Data on S(IO3)2 by Materials Project

S(O3I)2 crystallizes in the monoclinic C2/c space group. The structure is two-dimensional and consists of two S(O3I)2 sheets oriented in the (0, 0, 1) direction. S2+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.49 Å) and two longer (1.51 Å) S–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one S2+ and one I5+ atom. The O–I bond length is 2.46 Å. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one S2+ and one I5+ atom. The O–I bond length is 2.38 Å. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent I5+ atoms. There are one shorter (2.00 Å) and one longer (2.01 Å) O–I bond lengths. I5+ is bonded in a square co-planar geometry to four O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Competitive TcO4-, IO3-, and CrO42- Incorporation into Ettringite

Ettringite is a naturally occurring mineral found in cementitious matrices that is known for its ability to incorporate environmentally mobile oxyanion contaminants. To better assess this immobilization mechanism for contaminants within cementitious waste forms intended for nuclear waste storage, this work explores how mixed oxyanion contaminants compete for ettringite incorporation and influence the evolving mineralogy. Ettringite was precipitated in the presence of TcO4-, IO3-, and/or CrO42-, known contaminants of concern to nuclear waste treatment, over pre-determined precipitation periods. Solution analyses quantified contaminant removal and the collected solid was characterized using bulk and microprobe XRD coupled with PDF and microprobe XRF analyses. Results suggest that =96% IO3- is removed from solution, regardless of ettringite precipitation time or the presence of TcO4- or CrO42-. However, TcO4- removal remained <20%, was not significantly improved with longer ettringite precipitation times, and significantly decreased in the presence of IO3-. When IO3- is comingled with CrO42, gypsum is formed as a secondary mineral phase, which results in oxyanion partitioning among mineral phases, e.g., IO3- incorporation into ettringite and CrO42- incorporation into gypsum via SO42- substitution. Results from this work exemplify the importance of competitive immobilization when assessing waste form performance and environmental risk of contaminant release.

Gillispie, Elizabeth C.↗