AVS 63rd International Symposium & Exhibition
    In-Situ and Operando Spectroscopy and Microscopy for Catalysts, Surfaces, & Materials Focus Topic Wednesday Sessions
       Session IS+HC-WeA

Paper IS+HC-WeA3
In situ AP-XPS and NEXAFS Studies on CO Oxidation and CO2 Dissociation on Copper Surfaces

Wednesday, November 9, 2016, 3:00 pm, Room 101C

Session: Ambient Pressure XPS Studies of Surface and Chemistry of Catalysts
Presenter: Christian Heine, Lawrence Berkeley National Laboratory (LBNL)
Authors: B. Eren, Lawrence Berkeley National Laboratory (LBNL)
C. Heine, Lawrence Berkeley National Laboratory (LBNL)
G.A. Somorjai, Lawrence Berkeley National Laboratory (LBNL)
M.B. Salmeron, Lawrence Berkeley National Laboratory (LBNL)
Correspondent: Click to Email
This presentation contains three parts: 1- Surface science approach to CO oxidation reaction on the low-index Cu surfaces which shows at oxygen lean conditions where the Cu surface is not oxidized to Cu2O, (111) face of Cu is more active than more open (100) and (110) faces. This is due to high binding energy of atomic oxygen on Cu, i.e., poisoning of the lower coordinates sites of Cu. 2- Chemical state of the surface and subsurface, and adsorbate coverage on Cu(111) in steady state conditions. Here, we provide phase diagram of the surface under reaction conditions. Interestingly, no CuO phase occurs between 273K-413K when the CO:O2 ratio is chosen as 2:1 or above. Cu2O phase appears to be to more active phase, however it still unclean whether the reaction on Cu2O is a MvK or LH type. 3- Finally, we present the chemical state and the surface morphology of Cu during CO2 dissociation at ambient pressures, which appears to be different than in the presence of CO or O2 alone.