Photo-induced Charge Separation and Photoredox Catalysis in Cerium-Based Metal–Organic Frameworks
Abstract
Separation of photo-induced charges (electrons and holes) can exert important control over the lifetimes of photo-excited states. Such separation may be promoted in Metal–Organic frameworks (MOFs), which are organic–inorganic hybrid materials, through ligand-to-metal charge transfer (LMCT). Here, in this chapter, we discuss our recent work on photocatalysis with Ce-based MOFs, which feature LMCT due to the low-lying empty 4f states of Ce(IV). We discuss the electronic structure of Ce-based UiO-66, the effects of linker functionalization and metal (Zr or Ti) doping on the electronic structure of Ce-based UiO-66, and the photoredox possibilities of the selected Ce-MOFs.
- Authors:
-
- Univ. of Minnesota, Minneapolis, MN (United States)
- Publication Date:
- Research Org.:
- Univ. of Minnesota, Minneapolis, MN (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences & Biosciences Division (CSGB)
- OSTI Identifier:
- 2311171
- Grant/Contract Number:
- SC0008688; FG02-17ER16362
- Resource Type:
- Accepted Manuscript
- Journal Name:
- ACS Symposium Series
- Additional Journal Information:
- Journal Volume: 1331; Journal ID: ISSN 0097-6156
- Publisher:
- American Chemical Society (ACS)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Electrical conductivity; Ligand to metal charge transfer; Metal organic frameworks; Metals; Photocatalysts
Citation Formats
Wu, Xin-Ping, and Truhlar, Donald G. Photo-induced Charge Separation and Photoredox Catalysis in Cerium-Based Metal–Organic Frameworks. United States: N. p., 2019.
Web. doi:10.1021/bk-2019-1331.ch014.
Wu, Xin-Ping, & Truhlar, Donald G. Photo-induced Charge Separation and Photoredox Catalysis in Cerium-Based Metal–Organic Frameworks. United States. https://doi.org/10.1021/bk-2019-1331.ch014
Wu, Xin-Ping, and Truhlar, Donald G. Wed .
"Photo-induced Charge Separation and Photoredox Catalysis in Cerium-Based Metal–Organic Frameworks". United States. https://doi.org/10.1021/bk-2019-1331.ch014. https://www.osti.gov/servlets/purl/2311171.
@article{osti_2311171,
title = {Photo-induced Charge Separation and Photoredox Catalysis in Cerium-Based Metal–Organic Frameworks},
author = {Wu, Xin-Ping and Truhlar, Donald G.},
abstractNote = {Separation of photo-induced charges (electrons and holes) can exert important control over the lifetimes of photo-excited states. Such separation may be promoted in Metal–Organic frameworks (MOFs), which are organic–inorganic hybrid materials, through ligand-to-metal charge transfer (LMCT). Here, in this chapter, we discuss our recent work on photocatalysis with Ce-based MOFs, which feature LMCT due to the low-lying empty 4f states of Ce(IV). We discuss the electronic structure of Ce-based UiO-66, the effects of linker functionalization and metal (Zr or Ti) doping on the electronic structure of Ce-based UiO-66, and the photoredox possibilities of the selected Ce-MOFs.},
doi = {10.1021/bk-2019-1331.ch014},
journal = {ACS Symposium Series},
number = ,
volume = 1331,
place = {United States},
year = {Wed Dec 11 00:00:00 EST 2019},
month = {Wed Dec 11 00:00:00 EST 2019}
}
Free Publicly Available Full Text
Publisher's Version of Record
Other availability
Save to My Library
You must Sign In or Create an Account in order to save documents to your library.
Works referenced in this record:
Solar Fuels via Artificial Photosynthesis
journal, December 2009
- Gust, Devens; Moore, Thomas A.; Moore, Ana L.
- Accounts of Chemical Research, Vol. 42, Issue 12
Photosynthetic energy conversion: natural and artificial
journal, January 2009
- Barber, James
- Chem. Soc. Rev., Vol. 38, Issue 1
Solar Water Splitting Cells
journal, November 2010
- Walter, Michael G.; Warren, Emily L.; McKone, James R.
- Chemical Reviews, Vol. 110, Issue 11, p. 6446-6473
Photochemical splitting of water for hydrogen production by photocatalysis: A review
journal, September 2014
- Ismail, Adel A.; Bahnemann, Detlef W.
- Solar Energy Materials and Solar Cells, Vol. 128
Heterogeneous photocatalysis
journal, January 1993
- Fox, Marye Anne.; Dulay, Maria T.
- Chemical Reviews, Vol. 93, Issue 1
Environmental Applications of Semiconductor Photocatalysis
journal, January 1995
- Hoffmann, Michael R.; Martin, Scot T.; Choi, Wonyong.
- Chemical Reviews, Vol. 95, Issue 1
An overview of semiconductor photocatalysis
journal, July 1997
- Mills, Andrew; Le Hunte, Stephen
- Journal of Photochemistry and Photobiology A: Chemistry, Vol. 108, Issue 1
Heterogeneous photocatalyst materials for water splitting
journal, January 2009
- Kudo, Akihiko; Miseki, Yugo
- Chem. Soc. Rev., Vol. 38, Issue 1
Semiconductor-based Photocatalytic Hydrogen Generation
journal, November 2010
- Chen, Xiaobo; Shen, Shaohua; Guo, Liejin
- Chemical Reviews, Vol. 110, Issue 11
Semiconductor Photocatalysis — Past, Present, and Future Outlook
journal, February 2012
- Serpone, N.; Emeline, A. V.
- The Journal of Physical Chemistry Letters, Vol. 3, Issue 5
TiO2 photocatalysis: Design and applications
journal, September 2012
- Nakata, Kazuya; Fujishima, Akira
- Journal of Photochemistry and Photobiology C: Photochemistry Reviews, Vol. 13, Issue 3
Understanding TiO 2 Photocatalysis: Mechanisms and Materials
journal, May 2014
- Schneider, Jenny; Matsuoka, Masaya; Takeuchi, Masato
- Chemical Reviews, Vol. 114, Issue 19
Recent advances in semiconductors for photocatalytic and photoelectrochemical water splitting
journal, January 2014
- Hisatomi, Takashi; Kubota, Jun; Domen, Kazunari
- Chem. Soc. Rev., Vol. 43, Issue 22
Hierarchical photocatalysts
journal, January 2016
- Li, Xin; Yu, Jiaguo; Jaroniec, Mietek
- Chemical Society Reviews, Vol. 45, Issue 9
Improved photoinduced charge carriers separation in organic-inorganic hybrid photovoltaic devices
journal, July 2010
- Vaynzof, Yana; Kabra, Dinesh; Zhao, Lihong
- Applied Physics Letters, Vol. 97, Issue 3
Photo-induced Charge Separation across the Graphene–TiO 2 Interface Is Faster than Energy Losses: A Time-Domain ab Initio Analysis
journal, August 2012
- Long, Run; English, Niall J.; Prezhdo, Oleg V.
- Journal of the American Chemical Society, Vol. 134, Issue 34
Efficient organometal trihalide perovskite planar-heterojunction solar cells on flexible polymer substrates
journal, November 2013
- Docampo, Pablo; Ball, James M.; Darwich, Mariam
- Nature Communications, Vol. 4, Article No. 2761
Semiconductor Composites: Strategies for Enhancing Charge Carrier Separation to Improve Photocatalytic Activity
journal, December 2013
- Marschall, Roland
- Advanced Functional Materials, Vol. 24, Issue 17
Semiconductor heterojunction photocatalysts: design, construction, and photocatalytic performances
journal, January 2014
- Wang, Huanli; Zhang, Lisha; Chen, Zhigang
- Chemical Society Reviews, Vol. 43, Issue 15
Direct and indirect electron transfer at a semiconductor surface with an adsorbate: Theory and application to Ag3Si(111):H
journal, March 2010
- Leathers, Andrew S.; Micha, David A.; Kilin, Dmitri S.
- The Journal of Chemical Physics, Vol. 132, Issue 11
Roles of Cocatalysts in Photocatalysis and Photoelectrocatalysis
journal, March 2013
- Yang, Jinhui; Wang, Donge; Han, Hongxian
- Accounts of Chemical Research, Vol. 46, Issue 8
Synthetic Strategies, Structure Patterns, and Emerging Properties in the Chemistry of Modular Porous Solids†
journal, August 1998
- Yaghi, Omar M.; Li, Hailian; Davis, Charles
- Accounts of Chemical Research, Vol. 31, Issue 8, p. 474-484
Exceptionally Long-Lived Charge Separated State in Zeolitic Imidazolate Framework: Implication for Photocatalytic Applications
journal, June 2016
- Pattengale, Brian; Yang, Sizhuo; Ludwig, John
- Journal of the American Chemical Society, Vol. 138, Issue 26
Long-Lived Photoinduced Charge Separation in a Trinuclear Iron-μ 3 -oxo-based Metal–Organic Framework
journal, June 2017
- Hanna, Lauren; Kucheryavy, Pavel; Liu, Cunming
- The Journal of Physical Chemistry C, Vol. 121, Issue 25
Hybrid porous solids past, present, future
journal, January 2008
- Férey, Gérard
- Chem. Soc. Rev., Vol. 37, Issue 1, p. 191-214
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
Structural determination of a highly stable metal-organic framework with possible application to interim radioactive waste scavenging: Hf-UiO-66
journal, September 2012
- Jakobsen, Søren; Gianolio, Diego; Wragg, David S.
- Physical Review B, Vol. 86, Issue 12
Study of the inorganic substitution in a functionalized UiO-66 metal–organic framework
journal, January 2016
- Yasin, Alhassan Salman; Li, Jiangtian; Wu, Nianqiang
- Physical Chemistry Chemical Physics, Vol. 18, Issue 18
Thorium Terephthalates Coordination Polymers Synthesized in Solvothermal DMF/H 2 O System
journal, February 2015
- Falaise, Clément; Charles, Jean-Sébastien; Volkringer, Christophe
- Inorganic Chemistry, Vol. 54, Issue 5
Cerium-based metal organic frameworks with UiO-66 architecture: synthesis, properties and redox catalytic activity
journal, January 2015
- Lammert, Martin; Wharmby, Michael T.; Smolders, Simon
- Chemical Communications, Vol. 51, Issue 63
Three-Dimensional MOF-Type Architectures with Tetravalent Uranium Hexanuclear Motifs (U 6 O 8 )
journal, January 2013
- Falaise, Clément; Volkringer, Christophe; Vigier, Jean-François
- Chemistry - A European Journal, Vol. 19, Issue 17
Coordination polymers of uranium( iv ) terephthalates
journal, January 2015
- Falaise, Clément; Assen, Ayalew; Mihalcea, Ionut
- Dalton Transactions, Vol. 44, Issue 6
De facto methodologies toward the synthesis and scale-up production of UiO-66-type metal–organic frameworks and membrane materials
journal, January 2015
- Hu, Zhigang; Zhao, Dan
- Dalton Transactions, Vol. 44, Issue 44
Postsynthetic Modification of Zirconium Metal-Organic Frameworks: Postsynthetic Modification of Zirconium Metal-Organic Frameworks
journal, July 2016
- Marshall, Ross J.; Forgan, Ross S.
- European Journal of Inorganic Chemistry, Vol. 2016, Issue 27
Water Stable Zr-Benzenedicarboxylate Metal-Organic Frameworks as Photocatalysts for Hydrogen Generation
journal, August 2010
- Gomes Silva, Cláudia; Luz, Ignacio; Llabrés i. Xamena, Francesc X.
- Chemistry - A European Journal, Vol. 16, Issue 36
Studies on Photocatalytic CO 2 Reduction over NH 2 -Uio-66(Zr) and Its Derivatives: Towards a Better Understanding of Photocatalysis on Metal-Organic Frameworks
journal, September 2013
- Sun, Dengrong; Fu, Yanghe; Liu, Wenjun
- Chemistry - A European Journal, Vol. 19, Issue 42
Metal–organic frameworks for artificial photosynthesis and photocatalysis
journal, January 2014
- Zhang, Teng; Lin, Wenbin
- Chem. Soc. Rev., Vol. 43, Issue 16
Band gap modulation of functionalized metal–organic frameworks
journal, January 2014
- Musho, Terence; Li, Jiangtan; Wu, Nianqiang
- Phys. Chem. Chem. Phys., Vol. 16, Issue 43
Computational exploration of newly synthesized zirconium metal–organic frameworks UiO-66, -67, -68 and analogues
journal, January 2014
- Yang, Li-Ming; Ganz, Eric; Svelle, Stian
- J. Mater. Chem. C, Vol. 2, Issue 34
Understanding Intrinsic Light Absorption Properties of UiO-66 Frameworks: A Combined Theoretical and Experimental Study
journal, November 2015
- Hendrickx, Kevin; Vanpoucke, Danny E. P.; Leus, Karen
- Inorganic Chemistry, Vol. 54, Issue 22
A panchromatic modification of the light absorption spectra of metal–organic frameworks
journal, January 2016
- Otal, E. H.; Kim, M. L.; Calvo, M. E.
- Chemical Communications, Vol. 52, Issue 40
Electronic origins of photocatalytic activity in d0 metal organic frameworks
journal, March 2016
- Nasalevich, Maxim A.; Hendon, Christopher H.; Santaclara, Jara G.
- Scientific Reports, Vol. 6, Issue 1
Fabrication of Ce doped UiO-66/graphene nanocomposites with enhanced visible light driven photoactivity for reduction of nitroaromatic compounds
journal, October 2017
- Yang, Zhiwang; Xu, Xueqing; Liang, Xixi
- Applied Surface Science, Vol. 420
Missing Linkers: An Alternative Pathway to UiO-66 Electronic Structure Engineering
journal, March 2017
- De Vos, Arthur; Hendrickx, Kevin; Van Der Voort, Pascal
- Chemistry of Materials, Vol. 29, Issue 7
Revisiting the Incorporation of Ti(IV) in UiO-type Metal–Organic Frameworks: Metal Exchange versus Grafting and Their Implications on Photocatalysis
journal, October 2017
- Santaclara, Jara G.; Olivos-Suarez, Alma I.; Gonzalez-Nelson, Adrian
- Chemistry of Materials, Vol. 29, Issue 21
Cerium Metal–Organic Framework for Photocatalysis
journal, May 2018
- Wu, Xin-Ping; Gagliardi, Laura; Truhlar, Donald G.
- Journal of the American Chemical Society, Vol. 140, Issue 25
Metal doping in cerium metal-organic frameworks for visible-response water splitting photocatalysts
journal, January 2019
- Gagliardi, Laura; Truhlar, Donald G.
- The Journal of Chemical Physics, Vol. 150, Issue 4
Ab initio molecular-dynamics simulation of the liquid-metal–amorphous-semiconductor transition in germanium
journal, May 1994
- Kresse, G.; Hafner, J.
- Physical Review B, Vol. 49, Issue 20, p. 14251-14269
Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set
journal, July 1996
- Kresse, G.; Furthmüller, J.
- Computational Materials Science, Vol. 6, Issue 1, p. 15-50
Restoring the Density-Gradient Expansion for Exchange in Solids and Surfaces
journal, April 2008
- Perdew, John P.; Ruzsinszky, Adrienn; Csonka, Gábor I.
- Physical Review Letters, Vol. 100, Issue 13
Influence of the exchange screening parameter on the performance of screened hybrid functionals
journal, December 2006
- Krukau, Aliaksandr V.; Vydrov, Oleg A.; Izmaylov, Artur F.
- The Journal of Chemical Physics, Vol. 125, Issue 22
Projector augmented-wave method
journal, December 1994
- Blöchl, P. E.
- Physical Review B, Vol. 50, Issue 24, p. 17953-17979
Molecular excitation energies to high-lying bound states from time-dependent density-functional response theory: Characterization and correction of the time-dependent local density approximation ionization threshold
journal, March 1998
- Casida, Mark E.; Jamorski, Christine; Casida, Kim C.
- The Journal of Chemical Physics, Vol. 108, Issue 11
Energy‐adjusted a b i n i t i o pseudopotentials for the rare earth elements
journal, February 1989
- Dolg, M.; Stoll, H.; Preuss, H.
- The Journal of Chemical Physics, Vol. 90, Issue 3
Electronic Chemical Potentials of Porous Metal–Organic Frameworks
journal, February 2014
- Butler, Keith T.; Hendon, Christopher H.; Walsh, Aron
- Journal of the American Chemical Society, Vol. 136, Issue 7
Novel metal–organic framework linkers for light harvesting applications
journal, January 2014
- Foster, Michael E.; Azoulay, Jason D.; Wong, Bryan M.
- Chem. Sci., Vol. 5, Issue 5
Metal-Organic Framework (MOF) Compounds: Photocatalysts for Redox Reactions and Solar Fuel Production
journal, March 2016
- Dhakshinamoorthy, Amarajothi; Asiri, Abdullah M.; García, Hermenegildo
- Angewandte Chemie International Edition, Vol. 55, Issue 18
Photochemistry of Zr-based MOFs: ligand-to-cluster charge transfer, energy transfer and excimer formation, what else is there?
journal, January 2016
- Gutierrez, Mario; Cohen, Boiko; Sánchez, Félix
- Physical Chemistry Chemical Physics, Vol. 18, Issue 40
The effect of intramolecular quantum modes on free energy relationships for electron transfer reactions
journal, November 1975
- Ulstrup, Jens; Jortner, Joshua
- The Journal of Chemical Physics, Vol. 63, Issue 10
Quantum effects in electron-transfer reactions
journal, February 1981
- Siders, P.; Marcus, R. A.
- Journal of the American Chemical Society, Vol. 103, Issue 4
Density matrix treatment of non-adiabatic photoinduced electron transfer at a semiconductor surface
journal, December 2012
- Micha, David A.
- The Journal of Chemical Physics, Vol. 137, Issue 22
Photoinduced electron transfer at a Si(111) nanostructured surface: Effect of varying light wavelength, temperature, and structural parameters
journal, May 2013
- Hembree, Robert H.; Micha, David A.
- The Journal of Chemical Physics, Vol. 138, Issue 18
Photoemission study of energy-band alignments and gap-state density distributions for high-k gate dielectrics
journal, January 2001
- Miyazaki, Seiichi
- Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures, Vol. 19, Issue 6
Titanium Dioxide Nanomaterials: Synthesis, Properties, Modifications, and Applications
journal, July 2007
- Chen, Xiaobo; Mao, Samuel S.
- Chemical Reviews, Vol. 107, Issue 7
Band offsets of ultrathin high- oxide films with Si
journal, August 2008
- Bersch, Eric; Rangan, Sylvie; Bartynski, Robert Allen
- Physical Review B, Vol. 78, Issue 8
Electron Localization Determines Defect Formation on Ceria Substrates
journal, July 2005
- Esch, F.
- Science, Vol. 309, Issue 5735
Electron Localization in Defective Ceria Films: A Study with Scanning-Tunneling Microscopy and Density-Functional Theory
journal, June 2011
- Jerratsch, Jan-Frederik; Shao, Xiang; Nilius, Niklas
- Physical Review Letters, Vol. 106, Issue 24
Clustering of Oxygen Vacancies at : Critical Role of Hydroxyls
journal, February 2016
- Wu, Xin-Ping; Gong, Xue-Qing
- Physical Review Letters, Vol. 116, Issue 8
Oxygen Defects and Surface Chemistry of Ceria: Quantum Chemical Studies Compared to Experiment
journal, December 2012
- Paier, Joachim; Penschke, Christopher; Sauer, Joachim
- Chemical Reviews, Vol. 113, Issue 6
Unique Electronic and Structural Effects in Vanadia/Ceria-Catalyzed Reactions
journal, October 2015
- Wu, Xin-Ping; Gong, Xue-Qing
- Journal of the American Chemical Society, Vol. 137, Issue 41
Theoretical studies on the monomeric vanadium oxides supported by ceria: the atomic structures and oxidative dehydrogenation activities
journal, January 2015
- Wu, Xin-Ping; Liu, Juanjuan; Fan, Jie
- RSC Advances, Vol. 5, Issue 64
Fundamentals and Catalytic Applications of CeO 2 -Based Materials
journal, April 2016
- Montini, Tiziano; Melchionna, Michele; Monai, Matteo
- Chemical Reviews, Vol. 116, Issue 10
Ceria-based model catalysts: fundamental studies on the importance of the metal–ceria interface in CO oxidation, the water–gas shift, CO 2 hydrogenation, and methane and alcohol reforming
journal, January 2017
- Rodriguez, José A.; Grinter, David C.; Liu, Zongyuan
- Chemical Society Reviews, Vol. 46, Issue 7
Photocatalysis. A multi-faceted concept for green chemistry
journal, January 2009
- Ravelli, Davide; Dondi, Daniele; Fagnoni, Maurizio
- Chemical Society Reviews, Vol. 38, Issue 7
Effects of Single Metal-Ion Doping on the Visible-Light Photoreactivity of TiO 2
journal, December 2009
- Choi, Jina; Park, Hyunwoong; Hoffmann, Michael R.
- The Journal of Physical Chemistry C, Vol. 114, Issue 2
Introduction of a mediator for enhancing photocatalytic performance via post-synthetic metal exchange in metal–organic frameworks (MOFs)
journal, January 2015
- Sun, Dengrong; Liu, Wenjun; Qiu, Mei
- Chemical Communications, Vol. 51, Issue 11
Photocatalytic CO 2 reduction by a mixed metal (Zr/Ti), mixed ligand metal–organic framework under visible light irradiation
journal, January 2015
- Lee, Yeob; Kim, Sangjun; Kang, Jeung Ku
- Chemical Communications, Vol. 51, Issue 26
Tuning the properties of the UiO-66 metal organic framework by Ce substitution
journal, January 2015
- Nouar, Farid; Breeze, Matthew I.; Campo, Betiana C.
- Chemical Communications, Vol. 51, Issue 77
Titanium incorporated with UiO-66(Zr)-type Metal–Organic Framework (MOF) for photocatalytic application
journal, January 2016
- Wang, Aoning; Zhou, Yingjie; Wang, Zhoulu
- RSC Advances, Vol. 6, Issue 5
Microwave-induced fast incorporation of titanium into UiO-66 metal–organic frameworks for enhanced photocatalytic properties
journal, January 2017
- Tu, Jiping; Zeng, Xiaoliang; Xu, Fujian
- Chemical Communications, Vol. 53, Issue 23
Ti as Mediator in the Photoinduced Electron Transfer of Mixed-Metal NH 2 –UiO-66(Zr/Ti): Transient Absorption Spectroscopy Study and Application in Photovoltaic Cell
journal, March 2017
- Santiago Portillo, Andrea; Baldoví, Herme G.; García Fernandez, Maria Teresa
- The Journal of Physical Chemistry C, Vol. 121, Issue 12
Photoelectrolysis of water using semiconducting TiO2 crystals
journal, October 1975
- Nozik, A. J.
- Nature, Vol. 257, Issue 5525
Electrochemistry and photoelectrochemistry of iron(III) oxide
journal, January 1983
- Dare-Edwards, Martin P.; Goodenough, John B.; Hamnett, Andrew
- Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases, Vol. 79, Issue 9, 2027
Photocatalytic Water Splitting: Recent Progress and Future Challenges
journal, September 2010
- Maeda, Kazuhiko; Domen, Kazunari
- The Journal of Physical Chemistry Letters, Vol. 1, Issue 18, p. 2655-2661
Review of photocatalytic water-splitting methods for sustainable hydrogen production: Review: photocatalysis for sustainable hydrogen
journal, May 2016
- Acar, Canan; Dincer, Ibrahim; Naterer, Greg F.
- International Journal of Energy Research, Vol. 40, Issue 11
Photocatalytic Water Splitting—The Untamed Dream: A Review of Recent Advances
journal, July 2016
- Jafari, Tahereh; Moharreri, Ehsan; Amin, Alireza
- Molecules, Vol. 21, Issue 7
Photoassisted Electrolysis of Water by Irradiation of a Titanium Dioxide Electrode
journal, April 1975
- Wrighton, M. S.; Ginley, D. S.; Wolczanski, P. T.
- Proceedings of the National Academy of Sciences, Vol. 72, Issue 4