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  • [ X ]
    Öğe
    Computational study on a cobalt-based complex compound with amine ligand in X-doped (X = Co, Ru, Rh) Ca12Al14O33 functional material as an innovative catalyst by NaBH4 hydrolysis for determining hydrogen generation process
    (Pergamon-Elsevier Science Ltd, 2024) Celik, Fatih Ahmet; Karabulut, Ezman; Izgi, Mehmet Sait; Yilmaz, Mucahit; Onat, Erhan
    Sodium borohydride (NaBH4) has been generally studied as a source of hydrogen (H2) due to its important advantages with the development of support materials and catalysts for H2 release in the energy sector. In this context, we carry out molecular dynamics (MD) simulations by using extended tight-binding (xTB) model Hamiltonian based on density functional theory (DFT) and analyze the Ca12Al14O33 functional material doped X metals (X = Co, Ru, Rh) as a catalyst with [Co(III)(N3)3(C9H8N2)2] as complex compound with amine ligand from NaBH4 hydrolysis for H2 production. The use of a functional material doped by X metals causes to the high rate in H2 production when compared to without functional material doped by X metals. The increase of complex compound with amine ligand facilitates H2 production. Rh on the functional material displays the best catalytic performance compared to Ru and Co to increase the H2 production rate. Also, the increment of temperature has a positive effect on the H2 production rate with functional material doped Co, Ru and Rh metals. Thus, Ca12Al14O33 support material doped with noble metals appears promising as an innovative catalyst for H2 production.
  • [ X ]
    Öğe
    Molecular dynamics approach to efficient hydrogen generation process of Co-B catalysts decorating lanthanides (La, Ce, Pr, Nd) supported by flat-sheet and twisted ThMoB4-type graphene from NaBH4 hydrolysis: Insights from non-self-consistent GFN1-xTB method
    (Elsevier Science Sa, 2024) Celik, Fatih Ahmet; Karabulut, Ezman; Onat, Erhan; Izgi, Mehmet Sait; Yilmaz, Mucahit
    In this study, the promoter role on highly efficient hydrogen generation productivity and H-2 formation mechanisms of Co-B-X catalysts modified by rare earths (X = La, Ce, Pr, Nd) supported by flat-sheet and twisted ThMoB4-type graphene from sodium borohydride (NaBH4) hydrolysis was investigated using molecular dynamics (MD) method based on non-self-consistent tight binding GFN1-xTB Method. The twisted ThMoB4-type graphene layer was constructed by adsorbing of ethylene carbonate (EC) molecule on armchair site of graphene surface with applying of geometric optimization process. The addition of Nd to CoB exhibited to higher H-2 release compared to other CoB containing lanthanides (La, Ce and Pr) both flat-sheet and twisted ThMoB4-type graphene. While the number of H-2 for Co-B-Nd is 14, the H-2 amount is only 8 for Co-B-Ce supported flat-sheet graphene at the end of simulation time. Also, the placing of twisted graphene instead of flat-sheet in the catalytic complex led to about 36 % increase in H-2 number for Co-B-Nd. The computational results revealed that the availability of the active sites, such as basicity of catalytic environment related to OH and H species and the mobility of Co atom, played an important role for catalytic activity and performance for H-2 production. This work can provide new insight for experimental studies of Co-B-X (X = La, Ce, Pr, Nd) catalysts for hydrogen production in atomic-level and the creation of new hydrogen energy applications and facilitates for H-2 generation efficiency.