how-reproducible-are-surface-areas-calculated-from-the-bet-equation

2 How reproducible are surface areas calculated from the BET equation? Johannes W M Osterrietha, James Rampersada, David Maddena, Nakul Rampala, Luka Skoricb, Bethany Connollya; Mark D Allendorfc, Vitalie Stavilac, Jonathan L Sniderc; Rob Amelootd, João Marreirosd; Conchi Aniae; Diana Azevedof, Enrique Vilarrasa-Garciaf, Bianca F Santosf; Xian-He Bug, Xe Zangg; Hana Bunzenh; Neil R Champnessi, Sarah L Griffini; Banglin Chenj, Rui-Biao Linj; Benoit Coasnek; Seth Cohenl, Jessica C Moretonl; Yamil J Colonm; Linjiang Chenn, Rob Clowesn; Franỗois-Xavier Couderto; Yong Cuip, Bang Houp; Deanna M D’Alessandroq, Patrick W Dohenyq; Mircea Dincăr, Chenyue Sunr; Christian Doonans, Michael Thomas Huxleys; Jack D Evanst; Paolo 10 Falcarou, Raffaele Riccou; Omar Farhav, Karam B Idreesv, Timur Islamogluv; Pingyun Fengw, 11 Huajun Yangw; Ross S Forganx, Dominic Barax; Shuhei Furukaway, Eli Sanchezy; Jorge Gasconz, 12 Selvedin Telalovicz; Sujit K Ghoshaa, Soumya Mukherjeeaa; Matthew R Hillab, Muhammad Munir 13 Sadiqab; Patricia Horcajadaac, Pablo Salcedo-Abrairaac; Katsumi Kanekoad, Radovan Kukobatad; 14 Jeff Kenvinae; Seda Keskinaf; Susumu Kitagawaag, Kenichi Otakeag; Ryan P Livelyah, Stephen J A 15 DeWittah; Phillip Llewellynaj; Bettina V Lotschaj,ak, Sebastian T Emmerlingaj,ak, Alexander M 16 Pützaj,ak; Carlos Martí-Gastaldoal, Natalia M Padialal; Javier García-Martínezam, Noemi Linaresam; 17 Daniel Maspochan,ao, Jose A Suárez del Pinoao; Peyman Moghadamap, Rama Oktavianap; Russel 18 E Morrisaq, Paul S Wheatleyaq; Jorge Navarroar; Camille Petitas, David Danacias; Matthew J 19 Rosseinskyat, Alexandros P Katsoulidisat; Martin Schröderau, Xue Hanau, Sihai Yangau; Christian 20 Serreav, Georges Mouchahamav; David S Shollah, Raghuram Thyagarajanah; Daniel Sideriusψ,φ,aw; 21 Randall Q Snurrax, Rebecca B Goncalvesay; Shane G Telferaz, Seok J Leeaz; Valeska P Tinba, 22 Jemma L Rowlandsonba; Takashi Uemurabb, Tomoya Iiyukabb; Monique A van der Veenbc, Davide 23 Regabc; Veronique Van Speybroeckbd, Sven M J Roggebd, Aran Lamairebd; Krista S Waltonah, 24 Lukas W Bingelah; Stefan Wuttkebe,bf, Jacopo Andreobe,bf; Omar Yaghibg,bh, Bing Zhangbg; Cafer T 25 Yavuzbi, Thien S Nguyenbi; Felix Zamorabj, Carmen Montorobj; Hongcai Zhoubk, Angelo Kirchonbk; 26 and David Fairen-Jimeneza,* 27 28 29 30 31 32 33 34 35 36 37 38 a Adsorption & Advanced Materials Laboratory (A2ML), Department of Chemical Engineering & Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge CB3 0AS, UK b Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE, Cambridge, United Kingdom c Sandia National Laboratories, 7011 East Avenue, Livermore, California 94550, United States d cMACS, Department of Microbial and Molecular Systems (M²S), KU Leuven, 3001 Leuven, Belgium CNRS (UPR 3079), Université d’Orléans, 45071 Orléans, France e CEMHTI, f LPACO2/GPSA, Department of Chemical Engineering, Federal University of Ceará, 60455-760 Fortaleza (CE), Brazil g School of Materials Science and Engineering, National Institute for Advanced Materials, Nankai University, Tianjin 300350, China 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 h Chair of Solid State and Materials Chemistry, Institute of Physics, University of Augsburg, Universitaetsstrasse 1, Augsburg 86159, Germany I School j of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD UK Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249- 0698, USA k Univ l Grenoble Alpes, CNRS, LIPhy, 38000 Grenoble, France Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California, 92093 USA m Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, IN, 46556, USA n Leverhulme Research Centre for Functional Materials Design, Materials Innovation Factory and Department of Chemistry, University of Liverpool, Liverpool, UK o Chimie p ParisTech, PSL University, CNRS, Institut de Recherche de Chimie Paris, 75005 Paris, France School of Chemistry and Chemical Engineering, Shanghai Jiaotong University, 800 Dongchuan Road, Minhang District, Shanghai q School of Chemistry, The University of Sydney, New South Wales, 2006, Australia r Department s Centre of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA for Advanced Nanomaterials and Department of Chemistry, The University of Adelaide, North Terrace, Adelaide, SA 5000, Australia t Department of Inorganic Chemistry, Technische Universität Dresden, Bergstrasse 66, 01062, Dresden, Germany u Institute v of Physical and Theoretical Chemistry, Graz University of Technology, Graz, Austria Department of Chemistry and International Institute of Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States w Department of Chemistry, University of California, Riverside, California 92521, USA x WestCHEM School of Chemistry, University of Glasgow, Glasgow, UK y Institute for Integrated Cell-Material Sciences, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan z KAUST Catalysis Center (KCC), King Abdullah University of Science and Technology, P.O.Box 4700, 23955- 6900, Thuwal-Jeddah, Kingdom od Saudi Arabia aa Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune, Dr Homi Bhabha Road, Pashan, Pune 411008, India ab CSIRO, Private Bag 33, Clayton South MDC, VIC 3169, Australia and Department of Chemical Engineering, Monash University, Clayton, VIC 3168, Australia ac Advanced Porous Materials Unit (APMU), IMDEA Energy, Avda Ramón de la Sagra 3, E-28935 Móstoles, Madrid, Spain ad Research Initiative for Supra-Materials, Shinshu University, Nagano, Japan ae Micromeritics af Instrument Corporation, Norcross, GA 30093, USA Department of Chemical and Biological Engineering, Koc University, Rumelifeneri Yolu 34450 Sariyer, Istanbul, Turkey ag Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University Institute for Advanced Study (KUIAS), Kyoto University, Yoshida Ushinomiya-cho, Sakyo-ku, Kyoto 606-8501, Japan ah School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 CNRS aj Max ak / Aix-Marseille Univ / TOTAL Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany Department of Chemistry, University of Munich (LMU), Butenandtstrasse 5-13, 81377 Munich, Germany al Instituto de Ciencia Molecular (ICMol), Universitat de València, Paterna 46980, València, Spain am Laboratorio de Nanotecnología Molecular, Departamento de Química Inorgánica, Universidad de Alicante, Ctra San Vicente-Alicante s/n, E-03690 San Vicente del Raspeig, Spain an ICREA, Pg Lluís Companys 23, Barcelona, 08010, Spain ao Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and the Barcelona Institute of Science and Technology Campus UAB, Bellaterra, 08193 Barcelona, Spain ap Department aq School of Chemical and Biological Engineering, University of Sheffield, Sheffield S1 3JD, UK of Chemistry, University of St Andrews, North Haugh, St Andrews, KY16 9ST, UK ar Departamento de Química Inorgánica, Universidad de Granada, 18071 Granada, Spain as Barrer Centre, Department of Chemical Engineering, Imperial College London, London, U.K., SW7 2AZ at Materials Innovation Factory, Department of Chemistry, University of Liverpool, Liverpool, L7 3NY, UK au School of Chemistry, The University of Manchester, Manchester, U.K M13 9PL av Institut des Matériaux Poreux de Paris, Ecole Normale Supérieure, ESPCI Paris, CNRS, PSL University, 75005 Paris, France aw Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland USA 20899-8320 ax Departments of Chemical & Biological Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA ay Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA az MacDiarmid Institute of Advanced Materials and Nanotechnology, School of Fundamental Sciences, Massey University, Palmerston North, New Zealand ba Department of Mechanical Engineering, University of Bristol, Bristol BS8 1TR, U.K bb Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan bc Department of Chemical Engineering, Delft University of Technology, van der Maasweg 9, 2629HZ Delft, the Netherlands bd Center for Molecular Modeling (CMM), Ghent University, Technologiepark 46, B-9052 Zwijnaarde, Belgium be BCMaterials, Basque Center for Materials, Applications and Nanostructures, UPV/EHU Science Park, 48940, Leioa, Spain bf bg IKERBASQUE, Basque Foundation for Science, 48009, Bilbao, Spain Department of Chemistry, University of California—Berkeley; Kavli Energy Nanoscience Institute at UC Berkeley bh Berkeley bi Global Science Institute, Berkeley, California 94720, United States Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Yuseong-gu, 34141 Daejeon, Korea bj Departamento de Qmica Inorgánica, Universidad Autónoma de Madrid, 28049 Madrid, Spain bk Chemistry Department -Texas A&M University ψ Official contribution of the National Institute of Standards and Technology (NIST), not subject to copyright in the United States of America 123 124 125 126 127 φ 128 To the editor: 129 The Brunauer-Emmett-Teller (BET) equation is arguably one of the most used equations in physical 130 chemistry and porosimetry Since its conception in the 1930s1 to estimate open surfaces whilst 131 working with adsorbents of the time such as Fe/Cu catalysts, silica gel, and charcoal, it has found 132 widespread use in the characterisation of synthetic zeolites.2 Furthermore, it gained considerable 133 momentum following the discovery of more complex porous materials such as mesoporous silicas,3 134 porous coordination polymers (PCPs),4 metal-organic frameworks (MOFs),5 and covalent organic 135 frameworks (COFs).6 Novel porous materials are of significant academic and industrial interest due 136 to their applications in gas storage and separation,7–10 catalysis,11 and drug delivery,12 and the BET 137 area is their de facto standard for the characterisation It has been recognized by the International 138 Union of Pure and Applied Chemistry (IUPAC) as “the most widely used procedure for evaluating 139 the surface area of porous and finely-divided materials”,13,14 and it has been an International 140 Organization for Standardization (ISO) standard for surface area determination since 1995.15 Whilst 141 concerns over the applicability of the BET theory for microporous materials are important, it remains, 142 arguably, the most important figure of merit for porous materials Given the broad use of the BET 143 equation, it is not surprising to see that much has been written on the applicability and the accuracy 144 of the BET theory – that is, its model of the adsorption process – and on the reproducibility of the 145 raw data, i.e the adsorption isotherm.16–20 Certain commercially available items may be identified in this paper This identification does not imply recommendation by NIST, nor does it imply that it is the best available for the purposes described * E-mail: df334@cam.ac.uk 146 The advent of materials with more complex pore networks and dynamic frameworks through 147 material design strategies such as reticular chemistry has boosted interest in BET theory (Figure 148 S1) and given rise to reported BET areas in excess of 8,000 m2 g-1.8,21,22 Often, these modern 149 materials have complex adsorption isotherms that are more problematic or ambiguous to fit to the 150 BET model, e.g several steps can occur due to different pore types and/or flexibility being present 151 in the material.23 Whilst adsorption rigs capable of ultra-low pressure (