CO2 dissociation over PtxNi4−x bimetallic clusters with and without hydrogen sources: A density functional theory study. (December 2016)

• Record Type: Journal Article
• Authors: Niu, Juntian; Ran, Jingyu; Ou, Zhiliang; Du, Xuesen; Wang, Ruirui; Qi, Wenjie; Zhang, Peng
• Is Part Of: Journal of CO₂ utilization. Volume 16(2016)
• Page Start: 431
• Page End: 441
• Publication Date: 2016-12
• Subjects: CO2 dissociation -- PtxNi4−x clusters -- Hydrogen sources -- DFT; Carbon dioxide -- Periodicals; Carbon dioxide -- Environmental aspects -- Periodicals; Carbon dioxide mitigation -- Periodicals; Carbon dioxide; Carbon dioxide -- Environmental aspects; Carbon dioxide mitigation; Periodicals; 628.53205
• DOI: 10.1016/j.jcou.2016.10.008
• Languages: English
• ISSNs: 2212-9820

Abstract

Highlights: CO2 dissociation with hydrogen sources proceeds more easily than direct dissociation. With the increase of Ni atoms in Ptx Ni4−x, the activation barriers show a moderate rise. The activity of bimetallic Pt-Ni for the reaction slightly lower than pure Pt. The cost of noble metal Pt catalysts will decrease with the addition of Ni. Abstract: Recently, CO2 activation and conversion is a well-attractive reaction that is of both scientific and industrial importance. In our present work, CO2 dissociation with and without hydrogen sources over Pt-Ni bimetallic catalysts have been studied by DFT systematically at the atomic scale. To address these processes, the detailed catalytic mechanisms of three bimetallic clusters Pt3 Ni1, Pt2 Ni2, Pt1 Ni3 to CO2 dissociation have been investigated, and their catalytic activities are compared with monometallic Pt4 and Ni4 clusters. The activation barrier values of CO2 dissociation with and without hydrogen sources on bimetallic Ptx Ni4−x clusters are both between the values of monometallic Pt4 and Ni4 clusters. Evidently, CO2 dissociation with hydrogen sources is much easier to be carried out than that without hydrogen sources for all five clusters. Catalysis for CO2 dissociation needs to be combined with hydrogen sources. In addition, with the increasing number of Ni atoms in Ptx Ni4−x clusters, the activation barriers present a moderate rise, indicating that Ni doping Pt cluster has a slight effect on the activity of Pt cluster for CO2 dissociation. As a result, the activity of bimetallic Pt-Ni for the reaction might be slightly lower than monometallic Pt, while, the cost of noble metal Pt catalysts will decrease with the addition of Ni.