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Title: Concentration Dependent Dimensionality of Resonance Energy Transfer in a Postsynthetically Doped Morphologically Homologous Analogue of UiO-67 MOF with a Ruthenium(II) Polypyridyl Complex

Abstract

In this study, a method is described here by which to dope ruthenium(II) bis(2,2'-bipyridine) (2,2'-bipyridyl-5,5'-dicarboxylic acid), RuDCBPY, into a UiO-67 metal–organic framework (MOF) derivative in which 2,2'-bipyridyl-5,5'-dicarboxylic acid, UiO-67-DCBPY, is used in place of 4,4'-biphenyldicarboxylic acid. Emission lifetime measurements of the RuDCBPY triplet metal-to-ligand charge transfer, 3MLCT, excited state as a function of RuDCBPY doping concentration in UiO-67-DCBPY are discussed in light of previous results for RuDCBPY-UiO-67 doped powders in which quenching of the 3MLCT was said to be due to dipole–dipole homogeneous resonance energy transfer, RET. The bulk distribution of RuDCBPY centers within MOF crystallites are also estimated with the use of confocal fluorescence microscopy. In the present case, it is assumed that the rate of RET between RuDCBPY centers has an r–6 separation distance dependence characteristic of Förster RET. The results suggest (1) the dimensionality in which RET occurs is dependent on the RuDCBPY concentration ranging from one-dimensional at very low concentrations up to three-dimensional at high concentration, (2) the occupancy of RuDCBPY within UiO-67-DCBPY is not uniform throughout the crystallites such that RuDCBPY densely populates the outer layers of the MOF at low concentrations, and (3) the average separation distance between RuDCBPY centers is ~21 Å.

Authors:
 [1];  [1];  [1]
  1. Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States)
Publication Date:
Research Org.:
Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
OSTI Identifier:
1185241
Alternate Identifier(s):
OSTI ID: 1454259
Grant/Contract Number:  
SC0012446; SN20074
Resource Type:
Published Article
Journal Name:
Journal of the American Chemical Society
Additional Journal Information:
Journal Volume: 137; Journal Issue: 25; Journal ID: ISSN 0002-7863
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Maza, William A., Padilla, Roberto, and Morris, Amanda J. Concentration Dependent Dimensionality of Resonance Energy Transfer in a Postsynthetically Doped Morphologically Homologous Analogue of UiO-67 MOF with a Ruthenium(II) Polypyridyl Complex. United States: N. p., 2015. Web. doi:10.1021/jacs.5b03071.
Maza, William A., Padilla, Roberto, & Morris, Amanda J. Concentration Dependent Dimensionality of Resonance Energy Transfer in a Postsynthetically Doped Morphologically Homologous Analogue of UiO-67 MOF with a Ruthenium(II) Polypyridyl Complex. United States. https://doi.org/10.1021/jacs.5b03071
Maza, William A., Padilla, Roberto, and Morris, Amanda J. Thu . "Concentration Dependent Dimensionality of Resonance Energy Transfer in a Postsynthetically Doped Morphologically Homologous Analogue of UiO-67 MOF with a Ruthenium(II) Polypyridyl Complex". United States. https://doi.org/10.1021/jacs.5b03071.
@article{osti_1185241,
title = {Concentration Dependent Dimensionality of Resonance Energy Transfer in a Postsynthetically Doped Morphologically Homologous Analogue of UiO-67 MOF with a Ruthenium(II) Polypyridyl Complex},
author = {Maza, William A. and Padilla, Roberto and Morris, Amanda J.},
abstractNote = {In this study, a method is described here by which to dope ruthenium(II) bis(2,2'-bipyridine) (2,2'-bipyridyl-5,5'-dicarboxylic acid), RuDCBPY, into a UiO-67 metal–organic framework (MOF) derivative in which 2,2'-bipyridyl-5,5'-dicarboxylic acid, UiO-67-DCBPY, is used in place of 4,4'-biphenyldicarboxylic acid. Emission lifetime measurements of the RuDCBPY triplet metal-to-ligand charge transfer, 3MLCT, excited state as a function of RuDCBPY doping concentration in UiO-67-DCBPY are discussed in light of previous results for RuDCBPY-UiO-67 doped powders in which quenching of the 3MLCT was said to be due to dipole–dipole homogeneous resonance energy transfer, RET. The bulk distribution of RuDCBPY centers within MOF crystallites are also estimated with the use of confocal fluorescence microscopy. In the present case, it is assumed that the rate of RET between RuDCBPY centers has an r–6 separation distance dependence characteristic of Förster RET. The results suggest (1) the dimensionality in which RET occurs is dependent on the RuDCBPY concentration ranging from one-dimensional at very low concentrations up to three-dimensional at high concentration, (2) the occupancy of RuDCBPY within UiO-67-DCBPY is not uniform throughout the crystallites such that RuDCBPY densely populates the outer layers of the MOF at low concentrations, and (3) the average separation distance between RuDCBPY centers is ~21 Å.},
doi = {10.1021/jacs.5b03071},
journal = {Journal of the American Chemical Society},
number = 25,
volume = 137,
place = {United States},
year = {2015},
month = {6}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record
https://doi.org/10.1021/jacs.5b03071

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Cited by: 113 works
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Works referenced in this record:

Post-synthetic modification of the metal–organic framework compound UiO-66
journal, January 2010

  • Kandiah, Mathivathani; Usseglio, Sandro; Svelle, Stian
  • Journal of Materials Chemistry, Vol. 20, Issue 44, p. 9848-9851
  • DOI: 10.1039/c0jm02416c

Postsynthetic Modification Switches an Achiral Framework to Catalytically Active Homochiral Metal−Organic Porous Materials
journal, June 2009

  • Banerjee, Mainak; Das, Sunirban; Yoon, Minyoung
  • Journal of the American Chemical Society, Vol. 131, Issue 22
  • DOI: 10.1021/ja901440g

Post-Synthetic Modification of Tagged Metal-Organic Frameworks
journal, October 2008

  • Burrows, Andrew D.; Frost, Christopher G.; Mahon, Mary F.
  • Angewandte Chemie International Edition, Vol. 47, Issue 44, p. 8482-8486
  • DOI: 10.1002/anie.200802908

Ground- and Excited-State Properties of Zn(II) Tetrakis(4-tetramethylpyridyl) Pophyrin Specifically Encapsulated within a Zn(II) HKUST Metal–Organic Framework
journal, October 2011

  • Larsen, Randy W.; Miksovska, Jaroslava; Musselman, Ronald L.
  • The Journal of Physical Chemistry A, Vol. 115, Issue 42
  • DOI: 10.1021/jp2064408

Photophysical Studies of Ru(II)tris(2,2′-bipyridine) Confined within a Zn(II)–Trimesic Acid Polyhedral Metal–Organic Framework
journal, July 2012

  • Larsen, Randy W.; Wojtas, Lukasz
  • The Journal of Physical Chemistry A, Vol. 116, Issue 30
  • DOI: 10.1021/jp302979a

Amplified Luminescence Quenching of Phosphorescent Metal–Organic Frameworks
journal, February 2012

  • Kent, Caleb A.; Liu, Demin; Meyer, Thomas J.
  • Journal of the American Chemical Society, Vol. 134, Issue 9
  • DOI: 10.1021/ja211271m

Rapid energy transfer in non-porous metal–organic frameworks with caged Ru(bpy)32+ chromophores: oxygen trapping and luminescence quenching
journal, January 2013

  • Kent, Caleb A.; Liu, Demin; Ito, Akitaka
  • Journal of Materials Chemistry A, Vol. 1, Issue 47
  • DOI: 10.1039/c3ta14009a

Light Harvesting in Microscale Metal–Organic Frameworks by Energy Migration and Interfacial Electron Transfer Quenching
journal, August 2011

  • Kent, Caleb A.; Liu, Demin; Ma, Liqing
  • Journal of the American Chemical Society, Vol. 133, Issue 33
  • DOI: 10.1021/ja204214t

Energy Transfer Dynamics in Metal−Organic Frameworks
journal, September 2010

  • Kent, Caleb A.; Mehl, Brian P.; Ma, Liqing
  • Journal of the American Chemical Society, Vol. 132, Issue 37
  • DOI: 10.1021/ja102804s

Triplet Excitation Energy Dynamics in Metal–Organic Frameworks
journal, June 2013

  • Lin, Jiaxing; Hu, Xiangqian; Zhang, Peng
  • The Journal of Physical Chemistry C, Vol. 117, Issue 43
  • DOI: 10.1021/jp401515r

Doping Metal–Organic Frameworks for Water Oxidation, Carbon Dioxide Reduction, and Organic Photocatalysis
journal, August 2011

  • Wang, Cheng; Xie, Zhigang; deKrafft, Kathryn E.
  • Journal of the American Chemical Society, Vol. 133, Issue 34, p. 13445-13454
  • DOI: 10.1021/ja203564w

Enhanced photovoltaic performance of Cu-based metal-organic frameworks sensitized solar cell by addition of carbon nanotubes
journal, February 2014

  • Lee, Deok Yeon; Shin, Chan Yong; Yoon, Seog Joon
  • Scientific Reports, Vol. 4, Issue 1
  • DOI: 10.1038/srep03930

Energy Transfer on Demand: Photoswitch-Directed Behavior of Metal–Porphyrin Frameworks
journal, August 2014

  • Williams, Derek E.; Rietman, Joseph A.; Maier, Josef M.
  • Journal of the American Chemical Society, Vol. 136, Issue 34
  • DOI: 10.1021/ja505589d

Ruthenium(II) Tris(2,2′-bipyridine)-Templated Zinc(II) 1,3,5-Tris(4-carboxyphenyl)benzene Metal Organic Frameworks: Structural Characterization and Photophysical Properties
journal, December 2013

  • Whittington, Christi L.; Wojtas, Lukasz; Larsen, Randy W.
  • Inorganic Chemistry, Vol. 53, Issue 1
  • DOI: 10.1021/ic402614w

A new photoactive Ru( ii )tris(2,2′-bipyridine) templated Zn( ii ) benzene-1,4-dicarboxylate metal organic framework: structure and photophysical properties
journal, January 2015

  • Whittington, Christi L.; Wojtas, Lukasz; Gao, Wen-Yang
  • Dalton Transactions, Vol. 44, Issue 12
  • DOI: 10.1039/C4DT02594F

Photocatalytic Carbon Dioxide Reduction with Rhodium-based Catalysts in Solution and Heterogenized within Metal-Organic Frameworks
journal, January 2015


Tailoring of network dimensionality and porosity adjustment in Zr- and Hf-based MOFs
journal, January 2013

  • Bon, Volodymyr; Senkovska, Irena; Weiss, Manfred S.
  • CrystEngComm, Vol. 15, Issue 45
  • DOI: 10.1039/c3ce41121d

Stability and degradation mechanisms of metal–organic frameworks containing the Zr6O4(OH)4 secondary building unit
journal, January 2013

  • DeCoste, Jared B.; Peterson, Gregory W.; Jasuja, Himanshu
  • Journal of Materials Chemistry A, Vol. 1, Issue 18
  • DOI: 10.1039/c3ta10662d

A facile synthesis of UiO-66, UiO-67 and their derivatives
journal, January 2013

  • Katz, Michael J.; Brown, Zachary J.; Colón, Yamil J.
  • Chemical Communications, Vol. 49, Issue 82
  • DOI: 10.1039/c3cc46105j

A New Zirconium Inorganic Building Brick Forming Metal Organic Frameworks with Exceptional Stability
journal, October 2008

  • Cavka, Jasmina Hafizovic; Jakobsen, Søren; Olsbye, Unni
  • Journal of the American Chemical Society, Vol. 130, Issue 42, p. 13850-13851
  • DOI: 10.1021/ja8057953

CH4 storage and CO2 capture in highly porous zirconium oxide based metal–organic frameworks
journal, January 2012

  • Yang, Qingyuan; Guillerm, Vincent; Ragon, Florence
  • Chemical Communications, Vol. 48, Issue 79, p. 9831-9833
  • DOI: 10.1039/c2cc34714h

H 2 storage in isostructural UiO-67 and UiO-66 MOFs
journal, January 2012

  • Chavan, Sachin; Vitillo, Jenny G.; Gianolio, Diego
  • Phys. Chem. Chem. Phys., Vol. 14, Issue 5
  • DOI: 10.1039/C1CP23434J

Disclosing the Complex Structure of UiO-66 Metal Organic Framework: A Synergic Combination of Experiment and Theory
journal, April 2011

  • Valenzano, Loredana; Civalleri, Bartolomeo; Chavan, Sachin
  • Chemistry of Materials, Vol. 23, Issue 7, p. 1700-1718
  • DOI: 10.1021/cm1022882

Combined study of structural properties on metal-organic frameworks with same topology but different linkers or metal
journal, April 2013


Modulated Synthesis of Zr-Based Metal-Organic Frameworks: From Nano to Single Crystals
journal, May 2011

  • Schaate, Andreas; Roy, Pascal; Godt, Adelheid
  • Chemistry - A European Journal, Vol. 17, Issue 24
  • DOI: 10.1002/chem.201003211

Detailed Structure Analysis of Atomic Positions and Defects in Zirconium Metal–Organic Frameworks
journal, October 2014

  • Øien, Sigurd; Wragg, David; Reinsch, Helge
  • Crystal Growth & Design, Vol. 14, Issue 11
  • DOI: 10.1021/cg501386j

A significant enhancement of water vapour uptake at low pressure by amine-functionalization of UiO-67
journal, January 2015

  • Ko, Nakeun; Hong, Jisu; Sung, Siyoung
  • Dalton Transactions, Vol. 44, Issue 5
  • DOI: 10.1039/C4DT02582B

Water Adsorption in Porous Metal–Organic Frameworks and Related Materials
journal, March 2014

  • Furukawa, Hiroyasu; Gándara, Felipe; Zhang, Yue-Biao
  • Journal of the American Chemical Society, Vol. 136, Issue 11, p. 4369-4381
  • DOI: 10.1021/ja500330a

High gas storage capacities and stepwise adsorption in a UiO type metal–organic framework incorporating Lewis basic bipyridyl sites
journal, January 2014

  • Li, Liangjun; Tang, Sifu; Wang, Chao
  • Chemical Communications, Vol. 50, Issue 18
  • DOI: 10.1039/c3cc48275h

Postsynthetic Metalation of Bipyridyl-Containing Metal–Organic Frameworks for Highly Efficient Catalytic Organic Transformations
journal, April 2014

  • Manna, Kuntal; Zhang, Teng; Lin, Wenbin
  • Journal of the American Chemical Society, Vol. 136, Issue 18
  • DOI: 10.1021/ja5018267

Single-Crystal-to-Single-Crystal Metalation of a Metal–Organic Framework: A Route toward Structurally Well-Defined Catalysts
journal, February 2015


Molecular Fluorescence
book, April 2012


Absorption spectra, luminescence properties, and electrochemical behavior of tris-heteroleptic ruthenium(II) polypyridine complexes
journal, October 1988

  • Juris, Alberto; Campagna, Sebastiano; Balzani, Vincenzo
  • Inorganic Chemistry, Vol. 27, Issue 20
  • DOI: 10.1021/ic00293a043

Ru(II) polypyridine complexes: photophysics, photochemistry, eletrochemistry, and chemiluminescence
journal, March 1988


Photophysical Characterization of a Ruthenium(II) Tris(2,2′-bipyridine)-Doped Zirconium UiO-67 Metal–Organic Framework
journal, April 2014

  • Maza, William A.; Morris, Amanda J.
  • The Journal of Physical Chemistry C, Vol. 118, Issue 17
  • DOI: 10.1021/jp501140r

Influence of Energy Transfer by the Exchange Mechanism on Donor Luminescence
journal, September 1965

  • Inokuti, Mitio; Hirayama, Fumio
  • The Journal of Chemical Physics, Vol. 43, Issue 6
  • DOI: 10.1063/1.1697063

Kinetics of Energy Transfer from the Triplet State in Rigid Solutions
journal, November 1967

  • Kellogg, R. E.
  • The Journal of Chemical Physics, Vol. 47, Issue 9
  • DOI: 10.1063/1.1712405

Theory of Fast and Slow Excitation Transfer Rates
journal, September 1974


Energy transfer with semiconductor nanocrystals
journal, January 2009

  • Rogach, Andrey L.; Klar, Thomas A.; Lupton, John M.
  • J. Mater. Chem., Vol. 19, Issue 9
  • DOI: 10.1039/B812884G

Fractal behavior in trapping and reaction
journal, January 1984

  • Klafter, J.; Blumen, A.
  • The Journal of Chemical Physics, Vol. 80, Issue 2
  • DOI: 10.1063/1.446743

Fractal behavior in trapping and reaction: A random walk study
journal, September 1984

  • Klafter, J.; Blumen, A.; Zumofen, G.
  • Journal of Statistical Physics, Vol. 36, Issue 5-6
  • DOI: 10.1007/BF01012922

Energy transfer in fractal structures
journal, December 1984


Fluorescence resonance energy transfer from allophycocyanin to malachite green
journal, August 1999


Photon-harvesting polymers
journal, December 1990


Photophysical processes on a latex surface: electronic energy transfer from rhodamine dyes to malachite green
journal, October 1993

  • Nakashima, K.; Duhamel, J.; Winnik, M. A.
  • The Journal of Physical Chemistry, Vol. 97, Issue 41
  • DOI: 10.1021/j100143a029

The Dynamics of Electronic Energy Transfer in Novel Multiporphyrin Functionalized Dendrimers:  A Time-Resolved Fluorescence Anisotropy Study
journal, March 2000

  • Ghiggino, Kenneth P.; Reek, Joost N. H.; Crossley, Maxwell J.
  • The Journal of Physical Chemistry B, Vol. 104, Issue 12
  • DOI: 10.1021/jp993116u

Critical evaluation of the application of direct energy transfer in probing the morphology of porous solids
journal, October 1988

  • Levitz, P.; Drake, J. M.; Klafter, J.
  • The Journal of Chemical Physics, Vol. 89, Issue 8
  • DOI: 10.1063/1.455613

Two-Dimensional Förster Resonant Energy Transfer in a Mixed Quantum Dot Monolayer: Experiment and Theory
journal, February 2009

  • Lunz, Manuela; Bradley, A. Louise; Chen, Wei-Yu
  • The Journal of Physical Chemistry C, Vol. 113, Issue 8
  • DOI: 10.1021/jp8087034

Picosecond fluorescence studies of energy transfer on the surface of poly(butyl methacrylate) latex particles
journal, November 1993

  • Nakashima, Kenichi; Liu, Yuan Sheng; Zhang, Ping
  • Langmuir, Vol. 9, Issue 11
  • DOI: 10.1021/la00035a017

Resonance energy transfer in a model system of membranes: application to gel and liquid crystalline phases
journal, October 1996


Förster-Type Energy Transfer along a Specified Axis
journal, August 2005

  • Minkowski, Claudia; Calzaferri, Gion
  • Angewandte Chemie International Edition, Vol. 44, Issue 33
  • DOI: 10.1002/anie.200500431

Electronic Energy Transfer on Fractals
journal, June 1984


Nanometal Surface Energy Transfer in Optical Rulers, Breaking the FRET Barrier
journal, March 2005

  • Yun, C. S.; Javier, A.; Jennings, T.
  • Journal of the American Chemical Society, Vol. 127, Issue 9
  • DOI: 10.1021/ja043940i

Assembly of Ruthenium-Based Complex into Metal–Organic Framework with Tunable Area-Selected Luminescence and Enhanced Photon-to-Electron Conversion Efficiency
journal, October 2014

  • Tang, Yanqun; He, Wanhong; Lu, Yanluo
  • The Journal of Physical Chemistry C, Vol. 118, Issue 44
  • DOI: 10.1021/jp5092174

Works referencing / citing this record:

Post-synthetic exchange (PSE) of UiO-67 frameworks with Ru/Rh half-sandwich units for visible-light-driven H 2 evolution and CO 2 reduction
journal, January 2018

  • Liao, Wei-Ming; Zhang, Jian-Hua; Wang, Zheng
  • Journal of Materials Chemistry A, Vol. 6, Issue 24
  • DOI: 10.1039/c8ta02962h

Multicenter Metal–Organic Framework‐Based Ratiometric Fluorescent Sensors
journal, February 2019


Energy transfer on a two-dimensional antenna enhances the photocatalytic activity of CO 2 reduction by metal–organic layers
journal, January 2019

  • Hu, Xuefu; Chen, Peican; Zhang, Cankun
  • Chemical Communications, Vol. 55, Issue 65
  • DOI: 10.1039/c9cc04594e

On the potential for nanoscale metal–organic frameworks for energy applications
journal, January 2019

  • Kuyuldar, Seher; Genna, Douglas T.; Burda, Clemens
  • Journal of Materials Chemistry A, Vol. 7, Issue 38
  • DOI: 10.1039/c9ta09896h

Unravelling Why and to What Extent the Topology of Similar Ce‐Based MOFs Conditions their Photodynamic: Relevance to Photocatalysis and Photonics
journal, July 2019

  • Caballero‐Mancebo, Elena; Cohen, Boiko; Smolders, Simon
  • Advanced Science, Vol. 6, Issue 19
  • DOI: 10.1002/advs.201901020

Chemical diversity in a metal–organic framework revealed by fluorescence lifetime imaging
journal, April 2018


A luminescent [Pd 4 Ru 8 ] 24+ supramolecular cage
journal, January 2018

  • Rota Martir, Diego; Cordes, David B.; Slawin, Alexandra M. Z.
  • Chemical Communications, Vol. 54, Issue 47
  • DOI: 10.1039/c8cc02104j

Self-Assembly of Tunable Heterometallic Ln-Ru Coordination Polymers with Near-Infrared Luminescence and Magnetocaloric Effect
journal, January 2017

  • Wang, Lei; Xie, Zhigang; Dang, Song
  • Chemistry - A European Journal, Vol. 23, Issue 12
  • DOI: 10.1002/chem.201604869

Construction of metal–organic frameworks from 3-(6-oxo-6,9-dihydro-1H-purin-1-yl)propionate
journal, July 2017


Light-driven hydrogen evolution catalyzed by a cobaloxime catalyst incorporated in a MIL-101(Cr) metal–organic framework
journal, January 2018

  • Roy, Souvik; Bhunia, Asamanjoy; Schuth, Nils
  • Sustainable Energy & Fuels, Vol. 2, Issue 6
  • DOI: 10.1039/c8se00072g

Photonic hybrid crystals constructed from in situ host–guest nanoconfinement of a light-emitting complex in metal–organic framework pores
journal, January 2016

  • Chaudhari, Abhijeet K.; Ryder, Matthew R.; Tan, Jin-Chong
  • Nanoscale, Vol. 8, Issue 12
  • DOI: 10.1039/c6nr01122e

Photonic functional metal–organic frameworks
journal, January 2018

  • Cui, Yuanjing; Zhang, Jun; He, Huajun
  • Chemical Society Reviews, Vol. 47, Issue 15
  • DOI: 10.1039/c7cs00879a

A metal–organic framework film with a switchable anodic and cathodic behaviour in a photo-electrochemical cell
journal, January 2019

  • Ifraemov, Raya; Shimoni, Ran; He, Wenhui
  • Journal of Materials Chemistry A, Vol. 7, Issue 7
  • DOI: 10.1039/c8ta10483b

Recent Progress in Metal-Organic Frameworks for Applications in Electrocatalytic and Photocatalytic Water Splitting
journal, January 2017


Multifunctional Aromatic Carboxylic Acids as Versatile Building Blocks for Hydrothermal Design of Coordination Polymers
journal, February 2018


Light-driven hydrogen evolution catalyzed by a cobaloxime catalyst incorporated in a MIL-101(Cr) metal–organic framework
text, January 2018


Recent Progress in Metal-Organic Frameworks for Applications in Electrocatalytic and Photocatalytic Water Splitting
journal, January 2017


Light-driven hydrogen evolution catalyzed by a cobaloxime catalyst incorporated in a MIL-101(Cr) metal–organic framework
journal, January 2018

  • Roy, Souvik; Bhunia, Asamanjoy; Schuth, Nils
  • Sustainable Energy & Fuels, Vol. 2, Issue 6
  • DOI: 10.1039/c8se00072g