Selective surfaces

Quaternary Co(Ni)MoS-based chalcogels with divalent (Pb 2+, Cd 2+, Pd 2+) and trivalent (Cr 3+, Bi 3+) metals for gas separation

Kyriaki Polychronopoulou, Christos D. Malliakas, Jiaqing He, Mercouri G Kanatzidis

Research output: Contribution to journalArticle

34 Citations (Scopus)

Abstract

Porous chalcogels with tunable compositions of Co xM 1-xMoS 4 and Ni xM 1-xMoS 4, where M = Pd 2+, Pb 2+, Cd 2+, Bi 3+, or Cr 3+ and x = 0.3-0.7, were synthesized by metathesis reactions between the metal ions and MoS 4 2-. Solvent exchange, counterion removal and CO 2 supercritical drying led to the formation of aerogels. All chalcogels exhibited high surface areas (170-510 m 2/g) and pore volumes in the 0.56-1.50 cm 3/g range. Electron microscopy coupled with nitrogen adsorption measurements suggest the presence of both mesoporosity (2 nm <d <50 nm) and macroporosity (d > 50 nm, where d is the average pore size). Pyridine adsorption corroborated for the acid character of the aerogels. We present X-ray photoelectron spectroscopic and X-ray scattering evidence that the [MoS 4] 2- unit does not stay intact when bound to the metals in the chalcogel structure. The Mo 6+ species undergoes redox reactions during network assembly, giving rise to Mo 4+/5+-containing species where the Mo is bound to sulfide and polysulfide ligands. The chalcogels exhibit high adsorption selectivities for CO 2 and C 2H 6 over H 2, N 2, and CH 4 whereas specific compositions exhibited among the highest CO 2 enthalpy of adsorption reported so far for a porous material (up to 47 kJ/mol). The Co-Pb-MoS 4 and Co-Cr-MoS 4 chalcogels exhibited a 2-fold to 4-fold increase in CO 2/H 2 selectivity compared to ternary CoMoS 4 chalcogels.

Original languageEnglish
Pages (from-to)3380-3392
Number of pages13
JournalChemistry of Materials
Volume24
Issue number17
DOIs
Publication statusPublished - Sep 11 2012

Fingerprint

Carbon Monoxide
Gases
Metals
Adsorption
Aerogels
Polysulfides
Redox reactions
Sulfides
Photoelectrons
X ray scattering
Chemical analysis
Pyridine
Electron microscopy
Pore size
Metal ions
Porous materials
Enthalpy
Ion exchange
Drying
Nitrogen

Keywords

  • aerogels
  • chalcogenides
  • gas adsorption
  • porosity

ASJC Scopus subject areas

  • Materials Chemistry
  • Chemical Engineering(all)
  • Chemistry(all)

Cite this

Selective surfaces : Quaternary Co(Ni)MoS-based chalcogels with divalent (Pb 2+, Cd 2+, Pd 2+) and trivalent (Cr 3+, Bi 3+) metals for gas separation. / Polychronopoulou, Kyriaki; Malliakas, Christos D.; He, Jiaqing; Kanatzidis, Mercouri G.

In: Chemistry of Materials, Vol. 24, No. 17, 11.09.2012, p. 3380-3392.

Research output: Contribution to journalArticle

@article{d37da98f4f7c42e89340093a27a1fa4f,
title = "Selective surfaces: Quaternary Co(Ni)MoS-based chalcogels with divalent (Pb 2+, Cd 2+, Pd 2+) and trivalent (Cr 3+, Bi 3+) metals for gas separation",
abstract = "Porous chalcogels with tunable compositions of Co xM 1-xMoS 4 and Ni xM 1-xMoS 4, where M = Pd 2+, Pb 2+, Cd 2+, Bi 3+, or Cr 3+ and x = 0.3-0.7, were synthesized by metathesis reactions between the metal ions and MoS 4 2-. Solvent exchange, counterion removal and CO 2 supercritical drying led to the formation of aerogels. All chalcogels exhibited high surface areas (170-510 m 2/g) and pore volumes in the 0.56-1.50 cm 3/g range. Electron microscopy coupled with nitrogen adsorption measurements suggest the presence of both mesoporosity (2 nm 50 nm, where d is the average pore size). Pyridine adsorption corroborated for the acid character of the aerogels. We present X-ray photoelectron spectroscopic and X-ray scattering evidence that the [MoS 4] 2- unit does not stay intact when bound to the metals in the chalcogel structure. The Mo 6+ species undergoes redox reactions during network assembly, giving rise to Mo 4+/5+-containing species where the Mo is bound to sulfide and polysulfide ligands. The chalcogels exhibit high adsorption selectivities for CO 2 and C 2H 6 over H 2, N 2, and CH 4 whereas specific compositions exhibited among the highest CO 2 enthalpy of adsorption reported so far for a porous material (up to 47 kJ/mol). The Co-Pb-MoS 4 and Co-Cr-MoS 4 chalcogels exhibited a 2-fold to 4-fold increase in CO 2/H 2 selectivity compared to ternary CoMoS 4 chalcogels.",
keywords = "aerogels, chalcogenides, gas adsorption, porosity",
author = "Kyriaki Polychronopoulou and Malliakas, {Christos D.} and Jiaqing He and Kanatzidis, {Mercouri G}",
year = "2012",
month = "9",
day = "11",
doi = "10.1021/cm301444p",
language = "English",
volume = "24",
pages = "3380--3392",
journal = "Chemistry of Materials",
issn = "0897-4756",
publisher = "American Chemical Society",
number = "17",

}

TY - JOUR

T1 - Selective surfaces

T2 - Quaternary Co(Ni)MoS-based chalcogels with divalent (Pb 2+, Cd 2+, Pd 2+) and trivalent (Cr 3+, Bi 3+) metals for gas separation

AU - Polychronopoulou, Kyriaki

AU - Malliakas, Christos D.

AU - He, Jiaqing

AU - Kanatzidis, Mercouri G

PY - 2012/9/11

Y1 - 2012/9/11

N2 - Porous chalcogels with tunable compositions of Co xM 1-xMoS 4 and Ni xM 1-xMoS 4, where M = Pd 2+, Pb 2+, Cd 2+, Bi 3+, or Cr 3+ and x = 0.3-0.7, were synthesized by metathesis reactions between the metal ions and MoS 4 2-. Solvent exchange, counterion removal and CO 2 supercritical drying led to the formation of aerogels. All chalcogels exhibited high surface areas (170-510 m 2/g) and pore volumes in the 0.56-1.50 cm 3/g range. Electron microscopy coupled with nitrogen adsorption measurements suggest the presence of both mesoporosity (2 nm 50 nm, where d is the average pore size). Pyridine adsorption corroborated for the acid character of the aerogels. We present X-ray photoelectron spectroscopic and X-ray scattering evidence that the [MoS 4] 2- unit does not stay intact when bound to the metals in the chalcogel structure. The Mo 6+ species undergoes redox reactions during network assembly, giving rise to Mo 4+/5+-containing species where the Mo is bound to sulfide and polysulfide ligands. The chalcogels exhibit high adsorption selectivities for CO 2 and C 2H 6 over H 2, N 2, and CH 4 whereas specific compositions exhibited among the highest CO 2 enthalpy of adsorption reported so far for a porous material (up to 47 kJ/mol). The Co-Pb-MoS 4 and Co-Cr-MoS 4 chalcogels exhibited a 2-fold to 4-fold increase in CO 2/H 2 selectivity compared to ternary CoMoS 4 chalcogels.

AB - Porous chalcogels with tunable compositions of Co xM 1-xMoS 4 and Ni xM 1-xMoS 4, where M = Pd 2+, Pb 2+, Cd 2+, Bi 3+, or Cr 3+ and x = 0.3-0.7, were synthesized by metathesis reactions between the metal ions and MoS 4 2-. Solvent exchange, counterion removal and CO 2 supercritical drying led to the formation of aerogels. All chalcogels exhibited high surface areas (170-510 m 2/g) and pore volumes in the 0.56-1.50 cm 3/g range. Electron microscopy coupled with nitrogen adsorption measurements suggest the presence of both mesoporosity (2 nm 50 nm, where d is the average pore size). Pyridine adsorption corroborated for the acid character of the aerogels. We present X-ray photoelectron spectroscopic and X-ray scattering evidence that the [MoS 4] 2- unit does not stay intact when bound to the metals in the chalcogel structure. The Mo 6+ species undergoes redox reactions during network assembly, giving rise to Mo 4+/5+-containing species where the Mo is bound to sulfide and polysulfide ligands. The chalcogels exhibit high adsorption selectivities for CO 2 and C 2H 6 over H 2, N 2, and CH 4 whereas specific compositions exhibited among the highest CO 2 enthalpy of adsorption reported so far for a porous material (up to 47 kJ/mol). The Co-Pb-MoS 4 and Co-Cr-MoS 4 chalcogels exhibited a 2-fold to 4-fold increase in CO 2/H 2 selectivity compared to ternary CoMoS 4 chalcogels.

KW - aerogels

KW - chalcogenides

KW - gas adsorption

KW - porosity

UR - http://www.scopus.com/inward/record.url?scp=84866124135&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84866124135&partnerID=8YFLogxK

U2 - 10.1021/cm301444p

DO - 10.1021/cm301444p

M3 - Article

VL - 24

SP - 3380

EP - 3392

JO - Chemistry of Materials

JF - Chemistry of Materials

SN - 0897-4756

IS - 17

ER -