Iterlandes Machado Júnior, Matheus Araújo Pereira, Gabriel Henrique Sperandio, Kleryton Luiz Alves de Oliveira, Antonio Machado Netto, Fabrício V. de Andrade, Renata Pereira Lopes Moreira
High Resolution Image Download MS PowerPoint Slide Alkali-metal niobates MNbO 3 (M = Na, Li) decorated with platinum (Pt) nanoparticles (NPs) are innovatively utilized as catalytic supports for hydrogen (H 2 ) evolution from sodium borohydride (NaBH 4 ). Notably, a direct comparison between sodium niobate (NaNbO 3 ) and lithium niobate (LiNbO 3 ) in their efficiency for H 2 evolution from NaBH 4 was conducted for the first time, highlighting the distinct catalytic performance of these materials. The synthesis was confirmed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM). The deposited Pt nanoparticles remain below 10 nm. In this study, different transition-metal nanoparticles (M = Co, Ni, Pd, Pt) supported on NaNbO 3 and LiNbO 3 were evaluated as catalysts. The Pt NPs/NaNbO 3 and Pt NPs/LiNbO 3 catalysts demonstrated optimized performance, producing H 2 at similar rates of 2044.9 and 2303.7 mL min –1 g cat –1 at 293.15 K. Arrhenius plots indicate activation energies ( E a ) of 35.54 ± 1.32 kJ mol –1 for Pt NPs/NaNbO 3 and 35.04 ± 1.32 kJ·mol –1 for Pt NPs/LiNbO 3 . Additionally, the materials exhibited consistent stability, with an efficiency loss of less than 20% after the 10th cycle of use. These results underscore the potential of these catalysts for H 2 generation applications.