Acid hydrolysis of sodium borohydride by carbon dioxide releasing 4 equivalent H2 gas


Ergani S. K., Postallikara B., Akbayrak S., ÖZKAR S.

International Journal of Hydrogen Energy, cilt.269, 2026 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 269
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1016/j.ijhydene.2026.157191
  • Dergi Adı: International Journal of Hydrogen Energy
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Artic & Antarctic Regions, Chemical Abstracts Core, Chimica, Compendex, Environment Index, INSPEC, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO)
  • Anahtar Kelimeler: Acid hydrolysis, Carbon dioxide, Hydrogen release, Hydrolytic dehydrogenation, Sodium borohydride
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

Hydrogen generation from the hydrolysis of sodium borohydride is achieved using CO2 according to the equation: NaBH4(aq) + CO2(g) + 4H2O(l) → NaHCO3(aq) + H3BO3(aq) + 4H2(g). One mole of CO2 promotes the release of four equivalents of H2 while being simultaneously converted into bicarbonate. CO2 is initially dissolved in aqueous solution reaching the saturation under the conditions and then gradually evolves into bicarbonate during the reaction with NaBH4. The reaction products are identified unequivocally by 11B- and 13C- NMR spectroscopy. Increasing the initial NaBH4 concentration causes a decrease in hydrogen generation rate because the reaction becomes increasingly limited by the supply of dissolved CO2. These findings demonstrate that CO2 can simultaneously function as a mild acidic promoter for NaBH4 hydrolysis and as a reactant that is initially converted into bicarbonate in solution, providing new mechanistic insight into the coupling of hydrogen production with CO2 utilization.