Rh-M (M: Co, Cu, Fe) nanoclusters as highly efficient and durable catalysts for the methanolysis of ammonia borane


Abay B., Rakap M.

Catalysis Science & Technology, cilt.10, ss.7270-7279, 2020 (SCI Expanded İndekslerine Giren Dergi)

  • Cilt numarası: 10
  • Basım Tarihi: 2020
  • Dergi Adı: Catalysis Science & Technology
  • Sayfa Sayıları: ss.7270-7279

Özet

Herein, we report the preparation, characterization, and employment of hydroxyapatite-supported rhodiumbased

Rh–M (RhCo, RhCu, and RhFe) nanoclusters as cost-effective, highly efficient and reusable catalysts

for hydrogen evolution from ammonia borane methanolysis. Rh–M@HA nanoclusters are formed by in situ

reduction of hydroxyapatite-supported related metal cations during ammonia borane methanolysis after

ion-exchange. The Rh–M@HA nanoclusters are easily obtained as very stable solids and identified by some

advanced analytical techniques like ICP-OES, BET, TEM, XPS, and XRD. After experimental studies, they are

found as highly isolable, redispersible, and reusable nanocatalysts to evolve hydrogen from ammonia borane

methanolysis under mild conditions. From these three catalysts, the Rh51Co49@HA nanoclusters provide the

highest turnover frequency (TOF) value of 193.7 min−1 while the Rh26Cu74@HA and Rh45Fe55@HA

nanoclusters have TOF values of 25.1 and 38.7 min−1, respectively, in ammonia borane methanolysis at 25 ±

0.1 °C. The apparent activation energies (Ea) of the Rh51Co49@HA, Rh26Cu74@HA, and Rh45Fe55@HA

nanoclusters for the same reaction are calculated to be 52.7, 59.7, and 54.1 kJ mol−1, respectively.