Redox reactivity of methylene blue bound in pores of UMCM-1 metal-organic frameworks

Jonathan E Halls, Charles Y Cummings, Jonathan Ellis, Luke L Keenan, Dongmei Jiang, Andrew D Burrows, Frank Marken

Research output: Contribution to journalArticle

  • 6 Citations

Abstract

Redox processes were studied in the pores of a crystalline UMCM-1 metal organic framework (MOF) material. Methylene blue was employed as an absorbed redox active dye component. From the change in coloration during dye adsorption, it was concluded that an essentially irreversible adsorption process with high pore loading of the resulting MOF structure occurred. The adsorbed methylene blue remained redox active in the MOF pores and there was no evidence of significant losses during extended redox cycling. Due to the size of the pores, the reactivity of the pore-bound methylene blue is closely related to that expected for methylene blue in an aqueous solution. A study of the effect of solution pH on the voltammetric responses revealed an interesting gradual change in electrical pore conductivity form conducting poorly under acidic conditions to conducting very well under alkaline conditions. This is interpreted in terms of charge transport via single-electron hopping conduction in pores. An estimate of the apparent charge diffusion coefficient at pH 7, Dapp = 1.4 ̃ 10 -15 m 2s -2, is obtained. Potential applications of the new family of redox active hybrid MOF materials are indicated.
LanguageEnglish
Pages12-21
Number of pages10
JournalMolecular Crystals and Liquid Crystals
Volume554
Issue number1
DOIs
StatusPublished - 2012

Fingerprint

Methylene Blue
methylene blue
reactivity
Metals
porosity
metals
Coloring Agents
Dyes
organic materials
conduction
Adsorption
dyes
Charge transfer
adsorption
Oxidation-Reduction
Crystalline materials
Electrons
diffusion coefficient
aqueous solutions
color

Keywords

  • metal-organic frameworks
  • diffusion
  • electron transfer
  • voltammetry
  • ion conduction
  • coordination polymers
  • MOF
  • carbon dioxide
  • sensors
  • junction
  • electrolyte
  • pore
  • pH

Cite this

Redox reactivity of methylene blue bound in pores of UMCM-1 metal-organic frameworks. / Halls, Jonathan E; Cummings, Charles Y; Ellis, Jonathan; Keenan, Luke L; Jiang, Dongmei; Burrows, Andrew D; Marken, Frank.

In: Molecular Crystals and Liquid Crystals, Vol. 554, No. 1, 2012, p. 12-21.

Research output: Contribution to journalArticle

Halls, Jonathan E ; Cummings, Charles Y ; Ellis, Jonathan ; Keenan, Luke L ; Jiang, Dongmei ; Burrows, Andrew D ; Marken, Frank. / Redox reactivity of methylene blue bound in pores of UMCM-1 metal-organic frameworks. In: Molecular Crystals and Liquid Crystals. 2012 ; Vol. 554, No. 1. pp. 12-21
@article{0d05bdb916c0419c890b6967e27f0f60,
title = "Redox reactivity of methylene blue bound in pores of UMCM-1 metal-organic frameworks",
abstract = "Redox processes were studied in the pores of a crystalline UMCM-1 metal organic framework (MOF) material. Methylene blue was employed as an absorbed redox active dye component. From the change in coloration during dye adsorption, it was concluded that an essentially irreversible adsorption process with high pore loading of the resulting MOF structure occurred. The adsorbed methylene blue remained redox active in the MOF pores and there was no evidence of significant losses during extended redox cycling. Due to the size of the pores, the reactivity of the pore-bound methylene blue is closely related to that expected for methylene blue in an aqueous solution. A study of the effect of solution pH on the voltammetric responses revealed an interesting gradual change in electrical pore conductivity form conducting poorly under acidic conditions to conducting very well under alkaline conditions. This is interpreted in terms of charge transport via single-electron hopping conduction in pores. An estimate of the apparent charge diffusion coefficient at pH 7, Dapp = 1.4 ̃ 10 -15 m 2s -2, is obtained. Potential applications of the new family of redox active hybrid MOF materials are indicated.",
keywords = "metal-organic frameworks, diffusion, electron transfer, voltammetry, ion conduction, coordination polymers, MOF, carbon dioxide, sensors, junction, electrolyte, pore, pH",
author = "Halls, {Jonathan E} and Cummings, {Charles Y} and Jonathan Ellis and Keenan, {Luke L} and Dongmei Jiang and Burrows, {Andrew D} and Frank Marken",
year = "2012",
doi = "10.1080/15421406.2012.632738",
language = "English",
volume = "554",
pages = "12--21",
journal = "Molecular Crystals and Liquid Crystals",
issn = "1542-1406",
publisher = "Taylor & Francis",
number = "1",

}

TY - JOUR

T1 - Redox reactivity of methylene blue bound in pores of UMCM-1 metal-organic frameworks

AU - Halls,Jonathan E

AU - Cummings,Charles Y

AU - Ellis,Jonathan

AU - Keenan,Luke L

AU - Jiang,Dongmei

AU - Burrows,Andrew D

AU - Marken,Frank

PY - 2012

Y1 - 2012

N2 - Redox processes were studied in the pores of a crystalline UMCM-1 metal organic framework (MOF) material. Methylene blue was employed as an absorbed redox active dye component. From the change in coloration during dye adsorption, it was concluded that an essentially irreversible adsorption process with high pore loading of the resulting MOF structure occurred. The adsorbed methylene blue remained redox active in the MOF pores and there was no evidence of significant losses during extended redox cycling. Due to the size of the pores, the reactivity of the pore-bound methylene blue is closely related to that expected for methylene blue in an aqueous solution. A study of the effect of solution pH on the voltammetric responses revealed an interesting gradual change in electrical pore conductivity form conducting poorly under acidic conditions to conducting very well under alkaline conditions. This is interpreted in terms of charge transport via single-electron hopping conduction in pores. An estimate of the apparent charge diffusion coefficient at pH 7, Dapp = 1.4 ̃ 10 -15 m 2s -2, is obtained. Potential applications of the new family of redox active hybrid MOF materials are indicated.

AB - Redox processes were studied in the pores of a crystalline UMCM-1 metal organic framework (MOF) material. Methylene blue was employed as an absorbed redox active dye component. From the change in coloration during dye adsorption, it was concluded that an essentially irreversible adsorption process with high pore loading of the resulting MOF structure occurred. The adsorbed methylene blue remained redox active in the MOF pores and there was no evidence of significant losses during extended redox cycling. Due to the size of the pores, the reactivity of the pore-bound methylene blue is closely related to that expected for methylene blue in an aqueous solution. A study of the effect of solution pH on the voltammetric responses revealed an interesting gradual change in electrical pore conductivity form conducting poorly under acidic conditions to conducting very well under alkaline conditions. This is interpreted in terms of charge transport via single-electron hopping conduction in pores. An estimate of the apparent charge diffusion coefficient at pH 7, Dapp = 1.4 ̃ 10 -15 m 2s -2, is obtained. Potential applications of the new family of redox active hybrid MOF materials are indicated.

KW - metal-organic frameworks

KW - diffusion

KW - electron transfer

KW - voltammetry

KW - ion conduction

KW - coordination polymers

KW - MOF

KW - carbon dioxide

KW - sensors

KW - junction

KW - electrolyte

KW - pore

KW - pH

UR - http://www.scopus.com/inward/record.url?scp=84855911524&partnerID=8YFLogxK

UR - http://dx.doi.org/10.1080/15421406.2012.632738

U2 - 10.1080/15421406.2012.632738

DO - 10.1080/15421406.2012.632738

M3 - Article

VL - 554

SP - 12

EP - 21

JO - Molecular Crystals and Liquid Crystals

T2 - Molecular Crystals and Liquid Crystals

JF - Molecular Crystals and Liquid Crystals

SN - 1542-1406

IS - 1

ER -