%0 Journal Article %T Hydrogen transport property of polymer-derived cobalt cation-doped amorphous silica %+ IRCER - Axe 4 : céramiques sous contraintes environnementales (IRCER-AXE4) %A Tada, Shotaro %A Ando, Shiori %A Asaka, Toru %A Daiko, Yusuke %A Honda, Sawao %A Bernard, Samuel %A Iwamoto, Yuji %< avec comité de lecture %@ 2052-1553 %J Inorganic Chemistry Frontiers %I Royal Society of Chemistry %V 8 %P 90-99 %8 2021 %D 2021 %R 10.1039/d0qi01035a %K † Electronic supplementary information (ESI) available: Fig %K S1-S3 %K See %Z Chemical SciencesJournal articles %X The effect of the local structure of Co-doped amorphous silica on the hydrogen transport property was studied with the aim to improve the high-temperature hydrogen-permselectivity of microporous amorphous silica-based membranes. Co-Doped silica materials with measured Co/Si atomic ratios ranging from 0.01 to 0.18 were successfully synthesized through the polymer-derived ceramic (PDC) route. X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) analyses confirmed the amorphous state of the polymer-derived Co-doped silica, while both X-ray photoelectron and Fourier transform infrared (FT-IR) spectroscopy analyses revealed that the divalent Co cation (Co 2+) modified the matrix amorphous silica network to form hydrogen-bonded silanol. After dehydration treatment at 500°C in argon, hydrogen (H)/deuterium (D) isotope exchange behavior on the surface silanol groups (Si-OH/OD conversion) of the polymer-derived non-doped and Co-doped amorphous silica was in situ monitored by measuring diffuse reflectance infrared Fourier transform (DRIFT) spectra at 500°C. The self-diffusion coefficient for OH/OD conversion of free silanol groups of non-doped silica was 6.1 × 10 −15 m 2 s −1 , while that on the hydrogen bonded Si-OH was found to reach 15.6 × 10 −15 m 2 s −1 by Co-doping at the measured Co/Si atomic ratio of 0.05.The effect of the amount of Co 2+ doping on the hydrogen transport property was further studied by scanning transmission electron microscopy and electron energy loss spectroscopy (STEM-EELS) analyses, and it was suggested that a rather small amount of Co-doping, i.e. Co/Si atomic ratio of 0.05 was effective for enhancing high-temperature hydrogen permeance through microporous amorphous silica-based membranes. %G English %2 https://cnrs.hal.science/hal-03053425/document %2 https://cnrs.hal.science/hal-03053425/file/Version%3CHAL%3E.pdf %L hal-03053425 %U https://cnrs.hal.science/hal-03053425 %~ UNILIM %~ CNRS %~ SPCTS %~ IPAM %~ SPCTS-AXE4 %~ INC-CNRS %~ IRCER %~ IRCER-AXE4 %~ IMPEO %~ TEST2-HALCNRS