Coherence of interface between Pd and local tetrahedral symmetric Ni oxide intensifies local synergetic collaboration in CO2 thermal methanation
Che Yan1*, Chia-Hsin Wang2, Moore Lin3, Dinesh Bhalothia1, Shou-Shiun Yang1, Gang-Jei Fan3, Jia-Lin Wang3, Ting-Shan Chan2, Yao-lin Wang4, Xin Tu4, Sheng Dai5, Kuan-Wen Wang6, Jr-Hau He7, Tsan-Yao Chen1,8,9
1Department of Engineering and System Science, National Tsing Hua University, Hsinchu, Taiwan
2National Synchrotron Radiation Research Center, National Synchrotron Radiation Research Center, Taiwan
3Department of Chemistry, National Central University, Taoyuan, Taiwan
4Department of Electrical Engineering & Electronics, University of Liverpool, Liverpool, UK
5School ofChemistry & Molecular Engineering, East China University of Science and Technology, Shanghai, China
6Institute ofMaterials Science and Engineering, National Central University, Taoyuan, Taiwan
7Department ofMaterials Science and Engineering, City University ofHong Kong, Hong Kong
8Institute ofNuclear Engineering and Science, National Tsing Hua University, Hsinchu, Taiwan
9Hierarchical Green-Energy Materials (Hi-GEM) Research Centre, National Cheng Kung University, Tainan, Taiwan
* Presenter:Che Yan,
Synergetic collaboration is a vital mechanism in the nanometer regime for CO2 reduction reaction. Different molecule adsorption affinities (e.g. Hads, COads…) enable the intermediate reaction steps, such as dissociation of CO2, H2 splitting, and CO hydrogenation, to initiate simultaneously. In this study, the good coherence of the interface between metallic Pd and Ni oxide refers to a powerful synergetic collaboration. By cross-referencing the results of the physical structure inspections, in situ ambient pressure X-ray photoelectron spectroscopy, and gas chromatography-mass spectrometer analysis, the high concentration of Pd ions (denoted as NiOTPd30-T) introduces the galvanic replacement effect and builds a mismatched interface on Ni oxide, instead, the low concentration one (denoted as NiOTPd15-T) possesses an almost coherent interface. Indeed, the NiOTPd15-T nanocatalyst (NC) demonstrates both optimum production yields of 3629.5 μmol g-1catalyst of CO and 1905.1 μmol g-1catalyst of CH4 as compared to that of NiOTPd30-T at 573 K. Although the average area of the interface in one NiOTPd30-T nanoparticle is larger than that of NiOTPd15-T, the mismatched interface and the intermixing between the Pd atoms and Ni atoms weaken the local synergetic collaboration. Most importantly, this study exhibits the coherence of the interface between metal and metal oxide determines the effectiveness in the synergetic collaboration.

Keywords: Synergetic collaboration, CO2 reduction reaction, Nanocatalyst, wet chemical reduction