How Reproducible are Surface Areas Calculated from the BET Equation?
Authors: Osterrieth Johannes W. M. , Rampersad James , Madden David , Rampal Nakul , Skoric Luka , Connolly Bethany , Allendorf Mark D. , Stavila Vitalie , Snider Jonathan L. , Ameloot Rob , Marreiros João , Ania Conchi , Azevedo Diana , Vilarrasa‐Garcia Enrique , Santos Bianca F. , Bu Xian‐He , Chang Ze , Bunzen Hana , Champness Neil R. , Griffin Sarah L. , Chen Banglin , Lin Rui‐Biao , Coasne Benoit , Cohen Seth , Moreton Jessica C. , Colón Yamil J. , Chen Linjiang , Clowes Rob , Coudert François‐Xavier , Cui Yong , Hou Bang , D'Alessandro Deanna M. , Doheny Patrick W. , Dincă Mircea , Sun Chenyue , Doonan Christian , Huxley Michael Thomas , Evans Jack D. , Falcaro Paolo , Ricco Raffaele , Farha Omar , Idrees Karam B. , Islamoglu Timur , Feng Pingyun , Yang Huajun , Forgan Ross S. , Bara Dominic , Furukawa Shuhei , Sanchez Eli , Gascon Jorge , Telalović Selvedin , Ghosh Sujit K. , Mukherjee Soumya , Hill Matthew R. , Sadiq Muhammed Munir , Horcajada Patricia , Salcedo‐Abraira Pablo , Kaneko Katsumi , Kukobat Radovan , Kenvin Jeff , Keskin Seda , Kitagawa Susumu , Otake Ken‐ichi , Lively Ryan P. , DeWitt Stephen J. A. , Llewellyn Phillip , Lotsch Bettina V. , Emmerling Sebastian T. , Pütz Alexander M. , Martí‐Gastaldo Carlos , Padial Natalia M. , García‐Martínez Javier , Linares Noemi , Maspoch Daniel , Suárez del Pino Jose A. , Moghadam Peyman , Oktavian Rama , Morris Russel E. , Wheatley Paul S. , Navarro Jorge , Petit Camille , Danaci David , Rosseinsky Matthew J. , Katsoulidis Alexandros P. , Schröder Martin , Han Xue , Yang Sihai , Serre Christian , Mouchaham Georges , Sholl David S. , Thyagarajan Raghuram , Siderius Daniel , Snurr Randall Q. , Goncalves Rebecca B. , Telfer Shane , Lee Seok J. , Ting Valeska P. , Rowlandson Jemma L. , Uemura Takashi , Iiyuka Tomoya , van der Veen Monique A. , Rega Davide , Van Speybroeck Veronique , Rogge Sven M. J. , Lamaire Aran , Walton Krista S. , Bingel Lukas W. , Wuttke Stefan , Andreo Jacopo , Yaghi Omar , Zhang Bing , Yavuz Cafer T. , Nguyen Thien S. , Zamora Felix , Montoro Carmen , Zhou Hongcai , Kirchon Angelo , Fairen‐Jimenez David 
Published: May 2022

Porosity and surface area analysis play a prominent role in modern materials science. At the heart of this sits the Brunauer–Emmett–Teller (BET) theory, which has been a remarkably successful contribution to the field of materials science. The BET method was developed in the 1930s for open surfaces but is now the most widely used metric for the estimation of surface areas of micro‐ and mesoporous materials. Despite its widespread use, the calculation of BET surface areas causes a spread in reported areas, resulting in reproducibility problems in both academia and industry. To prove this, for this analysis, 18 already‐measured raw adsorption isotherms were provided to sixty‐one labs, who were asked to calculate the corresponding BET areas. This round‐robin exercise resulted in a wide range of values. Here, the reproducibility of BET area determination from identical isotherms is demonstrated to be a largely ignored issue, raising critical concerns over the reliability of reported BET areas. To solve this major issue, a new computational approach to accurately and systematically determine the BET area of nanoporous materials is developed. The software, called “BET surface identification” (BETSI), expands on the well‐known Rouquerol criteria and makes an unambiguous BET area assignment possible.