AVS 64th International Symposium & Exhibition
    Fundamental Discoveries in Heterogeneous Catalysis Focus Topic Wednesday Sessions
       Session HC+SA+SS-WeA

Paper HC+SA+SS-WeA2
The Mechanism of Oxygen Induced p(2×3) Reconstruction on Mo(112)

Wednesday, November 1, 2017, 2:40 pm, Room 24

Session: Bridging Gaps in Heterogeneously-Catalyzed Reactions
Presenter: Teng Ma, Shenyang Agricultural University, PR China
Correspondent: Click to Email
Oxygen induced reconstruction and oxidation of Mo(112) surface has shown various surface structures in model catalysis and surface studies. Because of its complexity, the p(2 × 3) reconstruction has been modeled as several patterns and its formation mechnism was not well clarified. In this report, a critical precursor of forming p(2 ×3) reconstruction has been observed by using STM, XPS and HREELS methods. For the Mo(112) surface exposed to 5.0×10-8 mbar O2, the formation of the p(2×3) reconstruction is a process of two consecutive steps, during which the clean metallic surface experience the initial oxidation to form dispersed oxide particles at nanoscale, and then reduction and structural rearrangement of molybdenum oxides to the ordered nanostructures. The features of surface structures are also temperature dependent, a mixture of dispersed nanoparticles of molybdenum oxide and one-dimensional nanostructures occurs after O2 dose at 605 K, while two-dimensional nanostructures or the p(2×3) reconstruction occurs until above 710 K. Our results would give a good explanation about some hurdled questions about the appearance of LEED streaky points and antidomain dislocations in the STM images of the p(2× 3) reconstruction.