Asian Journal of Research in Chemistry

Yamina Benkrima ¹, Abdelkader Souigat ², Mohammed Elbar Soudani ³, Mohammed Seyf Eddine Bougoffa ⁴, Zineb Korichi ⁵

Affiliations
1 Ecole Normale Supérieure de Ouargla, 30000 Ouargla, Algeria ., IN
2 Ecole Normale Supérieure de Ouargla, 30000 Ouargla, Algeria., IN
3 Laboratoire de Dévelopement des Energies Nouvelles et Renouvelables Dans les Zones Arides et Sahariennes, Faculté des Mathématiques et des Sciences de la Matière, Université Kasdi Merbah Ouargla, Ouargla 30000., IN
4 Laboratory of Materials Technology, Department of Materials Science, University of Science and Technology Houari Boumediene, Bp 32 El Alia, Bab Ezzouar, 16111, Algeria., IN
5 1Ecole Normale Supérieure de Ouargla, 30000 Ouargla, Algeria., IN

Abstract

In this paper, we present a systematic computational study based on the density function theory (DFT), Which aims to shed light on the potential effects of doped gold Au clusters with a platinum Pt atom,and finding the new structural and electronic properties that will be enjoyed by gold doped with platinum PtAun (n = 1-9) clusters, So that the most stable clusters are selected from the rest of the isomers for each cluster size. We doped Aun clusters with Pt atom, we obtained very interesting results, Stable and most stable structures reveal three-dimensional structures starting from (n=6), Also, the results of the fragmentation energy and the second difference in binding energy of these clusters in relation to their size have been studied in depth. The electronic properties, such as the Homo-Lumo gap energy, Vertical ionization potential (VIP) and adiabatic ionization potential (AIP) as a function of cluster size are also studied and discussed. All properties calculated by the generalized gradient approximation (GGA) were compared with the results of the local density approximation (LDA). Whereas, the results showed that the Aun clusters doped with Pt atom changed significantly.

Keywords

Density functional theory (DFT), Cluster, PtAun, Homo-Lumo gap, Chemical catalysis, Fragmentation energy.

Full Text

     

Yamina Benkrima ¹, Abdelkader Souigat ², Yassine Chaouche ³, Zineb Korichi ¹, Mohammed Elbar Soudani ⁴, Assia Belfar ¹

Affiliations
1 Ecole Normale Supérieure de Ouargla, 30000 Ouargla, Algeria., IN
2 Ecole Normale Supérieure de Ouargla, 30000 Ouargla, Algeria ., IN
3 Larbi Tebessi University, Tebessa, Laboratoire de Physique Appliquée et Théorique, Route de Constantine 12002 Tebessa, Algeria., IN
4 Laboratoire de Développement des Energies Nouvelles et Renouvelables dans les Zones Arides et Sahariennes, Faculté des Mathématiques et des Sciences de la Matière, Université Kasdi Merbah Ouargla, Ouargla 30000, AlgérieTebessi University, Tebessa, Laboratoire de Physique Appliquée et Théorique,, IN

Abstract

This search paper is focus on the investigation of the most stability structures of Pt3 and Cu3 clusters adsorbed on ZnO (000 ̅1) surfaces in the Wurtzite stable structure. The results are obtained by using the Density Function Theory (DFT). All the calculations are performed using the Gradient Generalized Approximation to describe the exchange correlation term in SIESTA code. From this work we found new structures of Pt3 and Cu3 clusters with lowest energy. Also we have calculated the binding energy, relaxation interlayer for each cluster, bond lengths, vertical ionization potential PIv and the density of states DOS. Through the results we found that the Pt3 cluster is more stable than Cu3 cluster and confirmed by the DOS, in the other hand the ZnO-O surface is more stable than ZnO-Zn surface. The computed electron structure and DOS illustrate that the Pt3/ZnO and Cu3/ZnO clusters adsorbed on ZnO-O surfaces display metallic characteristics.

Keywords

Ab initio calculations, Pt3 and Cu3 clusters, ZnO surfaces, Stability structure, electronic properties, catalysis.

Full Text

     

Yamina Benkrima ¹, Abdelkader Souigat ¹, Mohammed Elbar Soudani ², Mohammed Seyf Eddine Bougoffa ³, Zineb Korichi ⁴, Omar Bentouila ⁵

Affiliations
1 Ecole normale supérieure de Ouargla, 30000 Ouargla, Algeria., IN
2 Laboratoire de Développement des Energies Nouvelles et Renouvelables dans les Zones Arides et Sahariennes, Faculté des Mathématiques et des Sciences de la Matière, Université Kasdi Merbah Ouargla, Ouargla 30000., IN
3 laboratory of Materials Technology, Department of Materials Science, University of Science and Technology Houari Boumediene, Bp 32 El Alia, Bab Ezzouar, 16111, Algeria., IN
4 Ecole normale supérieure de Ouargla, 30000 Ouargla, Algeria ., IN
5 Department of Matter Sciences, Lenreza Laboratory, Optoelectronics Team, Faculty of Mathematics and Matter Sciences, Kasdi Merbah Ouargla University, Ouargla 30000, Algeria., IN

Abstract

In this work, we present a systematic theoretical study based on the density function theory (DFT), Through which we aim to shed light on the potential effects of dopped gold Au clusters with a platinum Pt atom, and the search for the new structural, chemical properties that gold clusters will have thanks to this doping, Where the study is limited to the selection of clusters with the lowest energy among the other isomers for each cluster size. The resulting stable structures with lower energy reveal three dimensional structures starting at n = 6, Doping Aun clusters with platinum Pt atom leads to improvement in all properties calculated for these clusters. The chemical and electronic properties have been studied and discussed, for example Vertical electronic affinity, adiabatic electronic affinity, enthalpy and chemical hardness as a function of cluster size. All properties were calculated using generalized gradient density approximation (GGA) and locus density approximation (LDA) and compared them with each other. Where it turns out that the results obtained are close to previous theoretical and experimental studies somewhat similar to them. This type of study is presented for the first time using the density function theory.

Keywords

Density Function Theory, doping, Cluster, Adiabatic electronic affinity, Enthalpy, chemical hardness.

Full Text

     

Yamina Benkrima ¹, Abdelkader Souigat ², Yassine Chaouche ³, Mohammed Elbar Soudani ⁴, Mohammed Seyf Eddine Bougoffa ⁵, Naouia Mahdadi ⁶

Affiliations
1 Ecole Normale Supérieure de Ouargla, 30000 Ouargla, Algeria ., IN
2 Ecole Normale Supérieure de Ouargla, 30000 Ouargla, Algeria., IN
3 Larbi Tebessi University, Tebessa, Laboratoire de Physique Appliquée et Théorique, Route de Constantine 12002 Tebessa, Algeria., IN
4 Laboratoire de Développement des Energies Nouvelles et Renouvelables dans les Zones Arides et Sahariennes, Faculté des Mathématiques et des Sciences de la Matière, Université Kasdi Merbah Ouargla, Ouargla 30000., IN
5 aboratory of Materials Technology, Department of Materials Science, University of Science and Technology Houari Boumediene, Bp 32 El Alia, Bab Ezzouar, 16111, Algeria., IN
6 Radiation, Plasmas and Surface Physics Laboratory, Physics Department, Ouargla University, Ouargla 30000, Algeria., IN

Abstract

In the current paper, we present a systematic calculation based on the Density functional theory (DFT), which aims to highlight the potential effects of doping platinum Pt clusters and the new electronic and light structural characteristics of platinum-infused gold clusters Aun (n= 1-9), so that less energy clusters are selected from the rest of the isomers per cluster size. The most stable structures with the lowest 3D structures starting from n=6. The average length of the bonds between the atoms of each cluster and the binding energy of these clusters is calculated relative to their size. Structural characteristics were studied, discussed and compared with all calculated properties by Gradient Density Approximation (GGA) with the Local Density Approximation (LDA), also highlighted the intensity of calculated cases and comparison of Au2 cluster with PtAu that the grafting of Aun clusters platinum Pt, makes them have characteristics that distinguish them to be qualified in their use of chemical stimulation

Keywords

Density functional theory, PtAun and Aun clusters, binding energy, Stability structure, chemical catalysis.

Full Text