Hafnium-doped silica nanotubes for the upgrading of glycerol into solketal: Enhanced performances and in-depth structure-activity correlation

Loraine Soumoy, Chloe Celis, Damien P. Debecker, Marco Armandi, Sonia Fiorilli, Carmela APRILE

Research output: Contribution to journalArticlepeer-review


An unprecedented type of Hf-doped silica nanotubes was synthesized using a straightforward one-pot sol–gel procedure. The well-defined nanotubes with a diameter of 14–20 nm exhibited high specific surface area and a widely open texture. The method – involving a key pH adjustment step – allowed a quantitative insertion of hafnium in the materials (Si/Hf = 74) and favored the insertion of Hf as dispersed species. Depending on the synthesis parameters, the chemical environment around Hf was modified, as evidenced by XPS, NH3-TPD and NH3-IR. Hf-doped silica nanotubes showed excellent activity in the conversion of glycerol to solketal, a reaction of high relevance in the context of biorefineries. Importantly, the turnover frequency and the acidity were unambiguously correlated with the insertion of Hf in the silica matrix. The best catalyst was proven to be stable and recyclable, and this sustainable reaction was also amenable to further catalytic enhancement upon optimized reaction conditions.
Original languageEnglish
Pages (from-to)41-53
Number of pages13
JournalJournal of Catalysis
Early online date14 May 2022
Publication statusPublished - Jul 2022


  • 1D tubular structures
  • Glycerol valorisation
  • Hf-silicates
  • Low E-factor
  • Solketal production

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