DOCSLIB.ORG

© Copyright 2020 Emily Rabe

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
© Copyright 2020 Emily Rabe © Copyright 2020 Emily Rabe The Role of Excited-State Energy Landscapes in Directing Electron and Proton Motion for Light Harvesting Applications Emily Rabe A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy University of Washington 2020 Reading Committee: Cody Schlenker, Chair Brandi Cossairt Munira Khalil Program Authorized to Offer Degree: Chemistry University of Washington Abstract The Role of Excited-State Energy Landscapes in Directing Electron and Proton Motion for Light Harvesting Applications Emily Rabe Chair of the Supervisory Committee: Professor Cody Schlenker Department of Chemistry To meet the increasing global demand for energy we need to innovate new ways to harness and convert renewable energy sources. Solar energy provides a huge potential to meet these demands, but there is still a plethora of unanswered questions surrounding how photons interact with organic molecules and materials, particularly in the field of photovoltaics and photochemistry. The low dielectric constant of these organic materials causes them to behave differently than their inorganic counterparts. Chapter 2 provides background for the variety of applications of organic optoelectronic materials and common techniques used to study them. In recent years, the aza-aromatic material carbon nitride, and its monomer unit, heptazine, has seen a surge in popularity to mediate photochemical transformations, particularly hydrogen evolution. Yet despite the thousands of publications in this field, there are few fundamental photophysical studies, which are critical to enable new reaction pathways. This work describes a series of photophysical explorations into a molecular heptazine derivative, 2,5,8-tris(4- methoxyphenyl)-1,3,4,6,7,9,9b-heptaazaphenalene (TAHz). Chapter 3 provides an overview of the photophysical and electrochemical properties of TAHz, including the unusual inversion of the lowest singlet and triplet state. Chapter 4 provides the first experimental evidence for excited-state proton-coupled electron transfer (ES-PCET) from water to a heptazine chromophore using time- resolved photoluminescence and radical scavenging. This first step of water oxidation opens a new range of possible photochemical reactions to harness solar energy. Chapter 5 proposes design rules for increasing reaction efficiency of ES-PCET with heptazine chromophores by studying reaction rates with a series of phenol derivatives. By adding electron-donating groups on phenol, increased reactivity and support the corollary: adding electron-withdrawing groups to heptazine could increase reaction efficiency with water. Chapter 6 considers another aspect of chromophore design by studying hydrogen bonding and how the local excited-state landscape is modulated by hydrogen-bond strength. Together, this work presents a holistic picture of heptazine’s photophysics with implications for tailoring organic chromophores to meet unique photochemical demands. TABLE OF CONTENTS List of Figures .............................................................................................................................v List of Tables ............................................................................................................................ ix Chapter 1. Introduction ...............................................................................................................1 1.1 Motivating Clean Energy Research ..............................................................................1 1.1.1 Increasing Global Energy Demand ...........................................................................1 1.1.2 Solar Energy Potential .............................................................................................2 1.1.3 Global Hydrogen Production ....................................................................................3 1.2 Photocatalytic Reactions ..............................................................................................4 1.2.1 Hydrogen Evolution .................................................................................................5 1.2.2 Proton-Coupled Electron Transfer ............................................................................5 1.3 History of Carbon Nitride and Heptazine .....................................................................7 1.4 References ...................................................................................................................9 Chapter 2. Background .............................................................................................................. 13 2.1 Photophysics of Organic Molecules ........................................................................... 13 2.1.1 Absorption of Light ............................................................................................... 13 2.1.2 Photoluminescence ................................................................................................ 15 2.1.3 Non-radiative rates ................................................................................................. 17 2.2 Methods for Studying Optoelectronic Materials ......................................................... 18 2.2.1 Lock-in Amplification............................................................................................ 18 2.2.2 Time-Resolved Photoluminescence ........................................................................ 21 2.3 Global Analysis ......................................................................................................... 23 i 2.4 Excited State Energies Drive Charge Transfer in Organic Materials ........................... 24 2.4.1 Introduction ........................................................................................................... 24 2.4.2 Depicting the Energy Landscape of OPV’s ............................................................ 25 2.4.3 Methods for Determining Energy Levels ................................................................ 30 2.5 References ................................................................................................................. 35 Chapter 3. Synthesis and Characterization of Heptazine Derivatives ......................................... 39 3.1 Synthesis of Tri-Anisole Heptazine (TAHz) ............................................................... 39 3.2 Characterizing TAHz Structure .................................................................................. 41 3.3 Understanding the Excited State Landscape of TAHz ................................................ 43 3.4 Singlet-Triplet Inversion in Heptazine ....................................................................... 51 3.4.1 Computational Results ........................................................................................... 53 3.4.2 Experimental Results ............................................................................................. 58 3.5 References ................................................................................................................. 63 Chapter 4. Proton-Coupled Electron Transfer from Water to a Model Heptazine-Based Molecular Photocatalyst ............................................................................................................................. 66 4.1 Summary ................................................................................................................... 66 4.2 Introduction ............................................................................................................... 66 4.3 Conclusions ............................................................................................................... 74 4.4 Experimental Methods ............................................................................................... 74 4.5 References ................................................................................................................. 77 Chapter 5. Barrierless Heptazine-Driven Excited-State Proton-Coupled Electron Transfer: Implications for Controlling Photochemistry of Carbon Nitrides and Aza-Arenes ..................... 81 ii 5.1 Introduction ............................................................................................................... 81 5.2 Results and Discussion .............................................................................................. 84 5.2.1 Association Constants for Hydrogen-Bonding ........................................................ 84 5.2.2 Quenching Constants for PhOH Derivatives........................................................... 86 5.2.3 Time-Resolved Photoluminescence ........................................................................ 89 5.2.4 Computational Studies of Hz-PhOH Complexes and Their Potential Energy Surfaces 92 5.2.5 Implications for Molecular Design ......................................................................... 95 5.3 Conclusions ............................................................................................................... 97 5.4 Experimental Methods ............................................................................................... 98 5.5 References ............................................................................................................... 101 Chapter 6. Intermolecular hydrogen bonding tunes vibronic coupling in heptazine complexes 104 6.1 Summary ................................................................................................................
Load more

Recommended publications
  • Facile Synthesis of Potassium Poly(Heptazine Imide) (PHIK)
    Subscriber access provided by CORNELL UNIVERSITY LIBRARY Article Facile synthesis of potassium poly(heptazine imide) (PHIK) / Ti-based Metal- Organic Framework (MIL-125-NH2) composites for photocatalytic applications Nicolás Artemio Rodríguez, Aleksandr Savateev, Maria Alejandra Grela, and Dariya Dontsova ACS Appl. Mater. Interfaces, Just Accepted Manuscript • Publication Date (Web): 13 Jun 2017 Downloaded from http://pubs.acs.org on June 14, 2017 Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.
    [Show full text]
  • Solar Energy Harvesting with Carbon Nitrides: Do We Understand The
    Solar energy harvesting with carbon nitrides: Do we understand the mechanism? Wolfgang Domcke1, Johannes Ehrmaier1 and Andrzej L. Sobolewski2 1 Department of Chemistry, Technical University of Munich, D-85747 Garching, Germany 2 Institute of Physics, Polish Academy of Sciences, 02-668 Warsaw, Poland Email: [email protected] (Wolfgang Domcke) Abstract The photocatalytic splitting of water into molecular hydrogen and molecular oxygen with sunlight is the dream reaction for solar energy conversion. Since decades, transition-metal- oxide semiconductors and supramolecular organometallic structures have been extensively explored as photocatalysts for solar water splitting. More recently, polymeric carbon nitride materials consisting of triazine or heptazine building blocks have attracted considerable attention as hydrogen-evolution photocatalysts. The mechanism of hydrogen evolution with polymeric carbon nitrides is discussed throughout the current literature in terms of the familiar concepts developed for photoelectrochemical water splitting with semiconductors since the 1970s. We discuss in this perspective an alternative mechanistic paradigm for photoinduced water splitting with carbon nitrides, which focusses on the specific features of the photochemistry of aromatic N-heterocycles in aqueous environments. It is shown that a water molecule which is hydrogen-bonded to an N-heterocycle can be decomposed into hydrogen and hydroxyl radicals by two simple sequential photochemical reactions. This concept is illustrated by first-principles calculations of excited-state reaction paths and their energy profiles for hydrogen-bonded complexes of pyridine, triazine and heptazine with a water molecule. It is shown that the excited-state hydrogen-transfer and hydrogen-detachment reactions are essentially barrierless, in sharp contrast to water oxidation in the electronic ground state, where high barriers prevail.
    [Show full text]
  • Photo-Induced Phenomena from the Quantum Chemist Point of View Tangui Le Bahers
    Photo-Induced Phenomena from the Quantum Chemist Point of View Tangui Le Bahers To cite this version: Tangui Le Bahers. Photo-Induced Phenomena from the Quantum Chemist Point of View. Theoretical and/or physical chemistry. Université Claude Bernard Lyon 1, 2018. tel-02073756 HAL Id: tel-02073756 https://hal.archives-ouvertes.fr/tel-02073756 Submitted on 22 Mar 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. MEMOIRE En vue de l’obtention du diplôme national de l’ Habilitation à diriger des recherches, délivré par l’Université Claude Bernard Lyon 1 Discipline : Chimie Laboratoire de Chimie de l’ENS Lyon Présenté publiquement le 14 Juin 2018 Par Monsieur Tangui LE BAHERS Photo-Induced Phenomena from the Quantum Chemist Point of View Devant le jury composé de : Dr. Valérie Keller CNRS / Université de Strasbourg Pr. Mario Barbatti Université d’Aix-Marseille Dr. Pascal Raybaud IFP Energies Nouvelles Dr. Filippo De Angelis CNR Perugia / Italy Pr. Christophe Morell Université Claude Bernard Lyon 1 Dr. Chantal Andraud CNRS / ENS Lyon Remerciements Voilà maintenant 7 ans que j’ai soutenu ma thèse. Ce manuscrit vient retracer les travaux scientifiques que j’ai réalisés depuis.
    [Show full text]
  • Graphitic Carbon Nitride (G-C3N4), an Organic Semiconductor That Proved a Suitable Photocatalyst for Hydrogen Production from Water
    METAL LOADED G-C₃N₄ FOR VISIBLE LIGHT-DRIVEN H₂ PRODUCTION Federica Fina A Thesis Submitted for the Degree of PhD at the University of St Andrews 2014 Full metadata for this item is available in St Andrews Research Repository at: http://research-repository.st-andrews.ac.uk/ Please use this identifier to cite or link to this item: http://hdl.handle.net/10023/6322 This item is protected by original copyright This item is licensed under a Creative Commons Licence Metal loaded g-C3N4 for visible light-driven H2 production by Federica Fina A thesis submitted in partial fulfilment for the degree of PhD at the University of St Andrews 2014 I, Federica Fina hereby certify that this thesis, which is approximately 50,000 words in length, has been written by me, and that it is the record of work carried out by me and that it has not been submitted in any previous application for a higher degree. I was admitted as a research student in January 2011 and as a candidate for the degree of Doctor of Philosophy in August 2014; the higher study for which this is a record was carried out in the University of St Andrews between 2011 and 2014. Date …………….………….. Signature of candidate …………….………….. I hereby certify that the candidate has fulfilled the conditions of the Resolution and Regulations appropriate for the degree of Doctor of Philosophy in the University of St Andrews and that the candidate is qualified to submit this thesis in application for that degree. Date …………….………….. Signature of supervisor …………….………….. In submitting this thesis to the University of St Andrews I understand that I am giving permission for it to be made available for use in accordance with the regulations of the University Library for the time being in force, subject to any copyright vested in the work not being affected thereby.
    [Show full text]
  • Heptazine Imide Salts Can Exchange Metal Cations in the Solid State
    MPIKG Public Access Author Manuscript Published in final edited form as: Savateev, A., Pronkin, S., Willinger, M. G., Antonietti, M., & Dontsova, D. (2017). Towards Organic Zeolites and Inclusion Catalysts: Heptazine Imide Salts Can Exchange Metal Cations in the Solid State. Chemistry – An Asian Journal, 12(13), 1517-1522. doi:10.1002/asia.201700209. Towards organic zeolites and inclusion catalysts: heptazine imide salts can exchange metal cations in the solid state Savateev, A., Pronkin, S., Willinger, M. G., Antonietti, M., & Dontsova, D. Worth its salt: A variety of heptazine imide salts and a free base can be easily prepared by a simple ion exchange starting from the synthesized potassium derivative. Thus, various mono- and bivalent cations can be incorporated in the structure that resembles the behavior of zeolites. The photocatalytic activity in visible-light-driven hydrogen evolution is shown to depend on the nature of the introduced cation and reaches its maximum in the case of the Mg-salt. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. Towards organic zeolites and inclusion catalysts: heptazine ipt imide salts can exchange metal cations in the solid state Aleksandr Savateev1, Sergey Pronkin2, Marc Willinger1,3, Markus Antonietti1, and Dariya Manuscr 1* Dontsova Abstract. Highly crystalline potassium (heptazine imides) were preparations. In addition, intercalation of chloride and prepared by the thermal condensation of substituted 1,2,4- · Author · bromide changes the gallery heights of the graphitic triazoles in eutectic salt melts. These semiconducting salts are already known to be highly active photocatalysts, e.g.
    [Show full text]
  • From Triazines to Heptazines: Novel Nonmetal Tricyanomelaminates As Precursors for Graphitic Carbon Nitride Materials
    Chem. Mater. 2006, 18, 1891-1900 1891 From Triazines to Heptazines: Novel Nonmetal Tricyanomelaminates as Precursors for Graphitic Carbon Nitride Materials Bettina V. Lotsch and Wolfgang Schnick* Department Chemie und Biochemie, Lehrstuhl fu¨r Anorganische Festko¨rperchemie, Ludwig-Maximilians-UniVersita¨t Mu¨nchen, Butenandtstrasse 5-13, D-81377 Mu¨nchen, Germany ReceiVed October 25, 2005. ReVised Manuscript ReceiVed December 22, 2005 The first non-metal tricyanomelaminates have been synthesized via metathesis reactions and characterized by means of single-crystal X-ray diffraction and vibrational and solid-state NMR spectroscopy. The crystal structures of [NH4]2[C6N9H] (1)(P21/c, a ) 1060.8(2) pm, b ) 1146.2(2) pm, c ) 913.32(18) pm, â ) 6 3 112.36(3)°, V ) 1027.0(4) × 10 pm ), [C(NH2)3]3[C6N9]‚2H2O(2)(P212121, a ) 762.12(15) pm, b ) 6 3 1333.6(3) pm, c ) 1856.6(4) pm, V ) 1887.0(7) × 10 pm ) and [C3N6H7]2[C6N9H]‚2.5 H2O(3)(P1h, a ) 1029.5(2) pm, b ) 1120.3(2) pm, c ) 1120.7(2) pm, R)104.22(3)°, â ) 112.74(3)°, γ ) 104.62- (3)°, V ) 1064.8(4) × 106 pm3) are composed of singly protonated (1 and 3) or nonprotonated (2) tricyanomelaminate ions, which, together with the respective counterions, form two-dimensional, layered structures (1 and 3) or a quasi three-dimensional network (2). Particular emphasis has been placed on the elucidation of the thermal reactivity of the three molecular salts by means of thermal analysis and vibrational and NMR spectroscopy, as well as temperature-dependent X-ray powder diffraction.
    [Show full text]
  • 2,5,8-Trihydrazino-S-Heptazine
    2,5,8-Trihydrazino-s-heptazine: a precursor for heptazine-based iminophosphoranes Edwin Kroke, Tatyana Saplinova, Vadym Bakumov, Tobias Gmeiner, Jörg Wagler, Marcus Schwarz To cite this version: Edwin Kroke, Tatyana Saplinova, Vadym Bakumov, Tobias Gmeiner, Jörg Wagler, et al.. 2,5,8- Trihydrazino-s-heptazine: a precursor for heptazine-based iminophosphoranes. Journal of Inorganic and General Chemistry / Zeitschrift für anorganische und allgemeine Chemie, Wiley-VCH Verlag, 2009, 10.1002/zaac.200900311. hal-00518304 HAL Id: hal-00518304 https://hal.archives-ouvertes.fr/hal-00518304 Submitted on 17 Sep 2010 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. ZAAC 2,5,8-Trihydrazino-s-heptazine: a precursor for heptazine- based iminophosphoranes Journal: Zeitschrift für Anorganische und Allgemeine Chemie Manuscript ID: zaac.200900311.R1 Wiley - Manuscript type: Article Date Submitted by the 17-Jul-2009 Author: Complete List of Authors: Kroke, Edwin; TU Bergakademie Freiberg, Institut fuer Anorganische Chemie Saplinova, Tatyana; TU Bergakademie Freiberg,
    [Show full text]
  • Investigations Into S-Heptazine-Based Carbon Nitride Precursors
    Dissertation zur Erlangung des Doktorgrades der Fakultät für Chemie und Pharmazie der Ludwig-Maximilians-Universität München Investigations into s-Heptazine-Based Carbon Nitride Precursors Andreas Sattler aus Augsburg 2010 Erklärung Diese Dissertation wurde im Sinne von § 13 Abs. 3 bzw. 4 der Promotionsordnung vom 29. Januar 1998 von Herrn Prof. Dr. Wolfgang Schnick betreut. Ehrenwörtliche Versicherung Diese Dissertation wurde selbstständig, ohne unerlaubte Hilfe erarbeitet. München, den 12.02.2010 Andreas Sattler Dissertation eingereicht am 15.02.2010 1. Gutachter: Prof. Dr. Wolfgang Schnick 2. Gutachter: Prof. Dr. Dirk Johrendt Mündliche Prüfung am 20. April 2010 ii Für meine Familie und Freunde Und für alle denen dies Information und Hilfe sein mag iii iv Acknowledgements First of all, I would like to express my gratitude to Prof. Dr. Wolfgang Schnick for hav- ing granted me the opportunity to work in his research group. His guidance and expertise have been invaluable for the present work. I am most grateful to Prof. Dr. Dirk Johrendt for his willingness to be the co-referee of this thesis. I thank Prof. Dr. Bettina V. Lotsch, Prof. Dr. Jürgen Senker, Prof. Dr. Konstantin Karaghiosoff and Priv. Doz. Dr. Klaus Müller-Buschbaum for being available as examiners in my viva-voce. The past and present members of the work group and other members of the department, whose company I have had the honor to enjoy, have helped and supported me in a multitude of ways. Working with these fine colleagues has become a part of my life that I will look back upon often and happily. I would like to address special thanks and gratitude to: My predecessors Dr.
    [Show full text]
  • Structure Elucidation of Polyheptazine Imide by Electron Diffraction
    View Article Online / Journal Homepage / Table of Contents for this issue COMMUNICATION www.rsc.org/chemcomm | ChemComm Structure elucidation of polyheptazine imide by electron diffraction—a templated 2D carbon nitride networkw Markus Do¨blinger,a Bettina V. Lotsch,a Julia Wack,b Ju¨rgen Thun,b Ju¨rgen Senkerb and Wolfgang Schnick*a Received (in Cambridge, UK) 10th November 2008, Accepted 9th January 2009 First published as an Advance Article on the web 27th January 2009 DOI: 10.1039/b820032g Structure elucidation of a condensed carbon(IV) nitride with a owing to the lack of single-crystal data. Electron diffraction is stoichiometry close to C3N4 by electron diffraction reveals a a powerful tool to deliver on both requirements by locally two-dimensional planar heptazine-based network containing probing the real structure of nanocrystalline materials and isolated melamine molecules in the trigonal voids. minority phases not previously accessible to bulk structural analysis. Owing to their exceptional chemical stability and hardness, Here, we communicate the structure elucidation of a crys- nitrides of main group elements have entered the stage as talline 2D carbon nitride network with the formula ubiquitous light-weight, high-performance materials relevant to (C6N7)2(NH)3ÁC3N3(NH2)3 by electron diffraction. This novel a multitude of technological applications. Although 3D phases of member of the carbon nitride family, featuring an intermediate binary carbon nitride C3N4 hold promise as new ultra-hard condensation stage halfway between melon and g-C3N4, may materials,1 the layered polymorph, graphitic carbon nitride shed light on structural implications and stability considerations (g-C3N4) has recently garnered attention for its versatile optical, associated with graphitic carbon nitride.
    [Show full text]
  • Fritz-Haber-Institut Der Max-Planck-Gesellschaft Berlin
    Fritz-Haber-Institut der Max-Planck-Gesellschaft Berlin 19th Meeting of the Fachbeirat Berlin, November 28th – 30th, 2017 Fritz-Haber-Institut der Max-Planck-Gesellschaft Berlin 19th Meeting of the Fachbeirat Berlin, November 28th – 30th, 2017 Reports Members of the Fachbeirat 2017 Prof. Dr. Roberto Car Prof. Dr. Hans-Peter Steinrück Princeton University Universität Erlangen-Nürnberg Department of Chemistry Physikalische Chemie II Frick Laboratory, 153 Egerlandstr. 3 Princeton, NJ 08544-1009 91058 Erlangen USA Germany +1 609-258-2534 +49 9131 85-27343 [email protected] [email protected] Prof. Dr. Tony Heinz Prof. Dr. Wataru Ueda Columbia University Kanagawa University Departments of Physics and Electrical Department of Material and Life Chemistry Engineering Faculty of Engineering 500 West 120th St. 3-27-1, Rokkakubashi, Kanagawa-ku New York, NY 10027 Yokohama, 221-8686 USA Japan +1 212 854 6564 +81-45-481-5661 [email protected] [email protected] Prof. Dr. Manfred Kappes Prof. Dr. Evan R. Williams Karlsruhe Institut für Technologie (KIT) University of California, Berkeley Institut für Physikalische Chemie Department of Chemistry Fritz-Haber-Weg 2 B84 Hildebrand Hall 76131 Karlsruhe Berkeley, CA 94720-1460 Germany USA +49 721 608-42094 +1 510-643-7161 [email protected] [email protected] Prof. Dr. Maki Kawai Prof. Dr. Weitao Yang Institute for Molecular Science Duke University 38 Nishigo-Naka, Myodaiji, Department of Chemistry Okazaki, 444-8585 5310 French Family Science Center Japan Durham, NC 27708-0346 +81-564-55-7103 USA [email protected] +1 919 660- 1562 [email protected] Prof.
    [Show full text]
  • Renewing Accessible Heptazine Chemistry
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Archive Ouverte en Sciences de l'Information et de la Communication Renewing accessible heptazine chemistry: 2,5,8-tris(3,5-diethyl-pyrazolyl)-heptazine, a new highly soluble heptazine derivative with exchangeable groups, and examples of newly derived heptazines and their physical chemistry Laurent Galmiche, Clémence Allain, Tuan Le, Régis Guillot, Pierre Audebert To cite this version: Laurent Galmiche, Clémence Allain, Tuan Le, Régis Guillot, Pierre Audebert. Renewing accessible heptazine chemistry: 2,5,8-tris(3,5-diethyl-pyrazolyl)-heptazine, a new highly soluble heptazine deriva- tive with exchangeable groups, and examples of newly derived heptazines and their physical chemistry. Chemical Science , The Royal Society of Chemistry, 2019, 10 (21), pp.5513-5518. 10.1039/c9sc00665f. hal-02276787 HAL Id: hal-02276787 https://hal.archives-ouvertes.fr/hal-02276787 Submitted on 3 Sep 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Distributed under a Creative Commons Attribution - NonCommercial| 4.0 International License Chemical Science View Article Online EDGE ARTICLE View Journal | View Issue Renewing accessible heptazine chemistry: 2,5,8- tris(3,5-diethyl-pyrazolyl)-heptazine, a new highly Cite this: Chem.
    [Show full text]
  • Polymeric Carbon Nitrides and Related Metal-Free Materials for Energy and Environmental Cite This: J
    Journal of Materials Chemistry A View Article Online REVIEW View Journal | View Issue Polymeric carbon nitrides and related metal-free materials for energy and environmental Cite this: J. Mater. Chem. A, 2020, 8, 11075 applications Jesus´ Barrio, Michael Volokh and Menny Shalom * Carbon nitride polymers have emerged as a new class of materials for a wide range of applications such as photo- and electro-catalysis, sensors, bioimaging and more due to their chemical, photophysical and catalytic properties as well as their low-price, facile synthesis and high stability under harsh chemical conditions. In this review we begin with a broad overview of carbon-based materials, arriving at the focus of this review, polymeric carbon nitrides (CNs). After a brief overview of applications, we delve into their various synthetic methods, with an emphasis on achieving control on the nanoscale features of this intriguing polymeric semiconductor. The main synthetic pathways include co- polymerization at various stages, templating, an ionothermal pathway and harnessing of Received 19th February 2020 Creative Commons Attribution 3.0 Unported Licence. supramolecular pre-organization, which are discussedindetailalongwithCNgrowthanddeposition Accepted 1st April 2020 on substrates. Finally, we give our perspectives on the evolution of this field, the current limitations, DOI: 10.1039/d0ta01973a and elaboration of achievable control over the chemical composition, the electronic structure and rsc.li/materials-a the morphology of this family of materials. 1. Carbon materials: synthesis, applications and challenges This article is licensed under a Carbon materials ranging from graphene,1 carbon nanotubes (CNTs)2 or fullerenes3 to activated carbon and aerogels4 are Department of Chemistry and Ilse Katz Institute for Nanoscale Science and widely used for environmental and energy-related purposes5–8 Open Access Article.
    [Show full text]