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{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2023,3,31]],"date-time":"2023-03-31T05:04:45Z","timestamp":1680239085268},"reference-count":84,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2023,3,30]],"date-time":"2023-03-30T00:00:00Z","timestamp":1680134400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008678","name":"Universit\u00e4t Leipzig","doi-asserted-by":"publisher"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Chem."],"abstract":"<jats:p>Surface-modified porous silica is a well-established composite material. To improve its embedding and application behavior, adsorption studies of various probe molecules have been performed using the technique of inverse gas chromatography (IGC). For this purpose, IGC experiments were carried out in the infinite dilution mode on macro-porous micro glass spheres before and after surface modification with (3-mercaptopropyl)trimethoxysilane. To provide information about the polar interactions between probe molecules and the silica surface, in particular, eleven polar molecules have been injected. In summary, the free surface energy for pristine silica (<jats:inline-formula><mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" id=\"m1\"><mml:mrow><mml:msubsup><mml:mi mathvariant=\"normal\">\u03b3<\/mml:mi><mml:mi mathvariant=\"normal\">S<\/mml:mi><mml:mrow><mml:mi mathvariant=\"normal\">t<\/mml:mi><mml:mi mathvariant=\"normal\">o<\/mml:mi><mml:mi mathvariant=\"normal\">t<\/mml:mi><mml:mi mathvariant=\"normal\">a<\/mml:mi><mml:mi mathvariant=\"normal\">l<\/mml:mi><\/mml:mrow><\/mml:msubsup><\/mml:mrow><\/mml:math><\/jats:inline-formula> = 229\u00a0mJ\/m<jats:sup>2<\/jats:sup>) and for (3-mercaptopropyl)trimethoxysilane-modified silica (<jats:inline-formula><mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" id=\"m2\"><mml:mrow><mml:msubsup><mml:mi mathvariant=\"normal\">\u03b3<\/mml:mi><mml:mi mathvariant=\"normal\">S<\/mml:mi><mml:mrow><mml:mi mathvariant=\"normal\">t<\/mml:mi><mml:mi mathvariant=\"normal\">o<\/mml:mi><mml:mi mathvariant=\"normal\">t<\/mml:mi><mml:mi mathvariant=\"normal\">a<\/mml:mi><mml:mi mathvariant=\"normal\">l<\/mml:mi><\/mml:mrow><\/mml:msubsup><\/mml:mrow><\/mml:math><\/jats:inline-formula> = 135\u00a0mJ\/m<jats:sup>2<\/jats:sup>) indicates a reduced wettability after surface modification. This is due to the reduction of the polar component of the free surface energy (<jats:inline-formula><mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" id=\"m3\"><mml:mrow><mml:msubsup><mml:mi mathvariant=\"normal\">\u03b3<\/mml:mi><mml:mi mathvariant=\"normal\">S<\/mml:mi><mml:mrow><mml:mi mathvariant=\"normal\">S<\/mml:mi><mml:mi mathvariant=\"normal\">P<\/mml:mi><\/mml:mrow><\/mml:msubsup><\/mml:mrow><\/mml:math><\/jats:inline-formula>) from 191\u00a0mJ\/m<jats:sup>2<\/jats:sup> to 105\u00a0mJ\/m<jats:sup>2<\/jats:sup>. Simultaneously, with the reduction of surface silanol groups caused by surface modification of silica and, therefore, the decrease in polar interactions, a substantial loss of Lewis acidity was observed by various IGC approaches. Experiments with all silica materials have been conducted at temperatures in the range from 90\u00b0C to 120\u00b0C to determine the thermodynamic parameters, such as adsorption enthalpy (<jats:inline-formula><mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" id=\"m4\"><mml:mrow><mml:msub><mml:mrow><mml:mo>\u0394<\/mml:mo><mml:mi>H<\/mml:mi><\/mml:mrow><mml:mrow><mml:mi>a<\/mml:mi><mml:mi>d<\/mml:mi><mml:mi>s<\/mml:mi><\/mml:mrow><\/mml:msub><\/mml:mrow><\/mml:math><\/jats:inline-formula>) and adsorption entropy (<jats:inline-formula><mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" id=\"m5\"><mml:mrow><mml:msub><mml:mrow><mml:mo>\u0394<\/mml:mo><mml:mi>S<\/mml:mi><\/mml:mrow><mml:mrow><mml:mi>a<\/mml:mi><mml:mi>d<\/mml:mi><mml:mi>s<\/
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