PdIn intermetallic nanoparticles for the hydrogenation of CO2 to methanol
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Direct hydrogenation of CO2 to methanol could offer significant environmental benefits, if efficient catalysts can be developed. Here, bimetallic Pd-In nanoparticles show good performance as catalysts for this reaction. Unsupported nanoparticles are synthesised by the thermal decomposition of Pd(acetate)2 and In(acetate)3 precursors in a high boiling point solvent (squalane), followed by reduction using dilute H2 gas (210 °C). Adjusting the ratio of the two metallic precursors allow access to 5–10 nm nanoparticles with different phase compositions, including metallic Pd(0), In2O3 and intermetallic PdIn. Liquid phase methanol synthesis experiments (50 bar, 210 °C, H2:CO2 = 3:1) identify the intermetallic PdIn nanoparticles as the most efficient. The catalysts exhibit around 70% higher methanol rates (normalised to the overall molar metal content) compared to the conventional heterogeneous Cu/ZnO/Al2O3 catalyst (900 and 540 μmol mmolPdInorCuZnAl−1 h−1, respectively). In addition, the optimum Pd/In catalyst shows an improved methanol selectivity over the whole temperature range studied (190–270 °C), reaching >80% selectivity at 270 °C, compared to only 45% for the reference Cu/ZnO/Al2O3 catalyst. Experiments showed an improvement in stability; the methanol production rate declined by 20% after 120 h run for the optimum PdIn-based compared with 30% for the Cu/ZnO/Al2O3 catalyst (after 25 h). The optimum catalyst consists of ∼8 nm nanoparticles comprising a surface In-enriched PdIn intermetallic phase as characterised by XRD, HR-TEM, STEM-EDX and XPS. Post-catalysis analysis of the optimum catalyst shows that the same PdIn bimetallic phase is retained with only a slight increase in the nanoparticle size.
Date Issued
2018-01-01
Date Acceptance
2017-07-24
Citation
Applied Catalysis B: Environmental, 2018, 220, pp.9-18
ISSN
0926-3373
Publisher
Elsevier
Start Page
9
End Page
18
Journal / Book Title
Applied Catalysis B: Environmental
Volume
220
Copyright Statement
© 2017 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Engineering & Physical Science Research Council (EPSRC)
Engineering & Physical Science Research Council (EPSRC)
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000412957200002&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Grant Number
EP/J021199/1
EP/K035274/1
EP/M013839/1
Subjects
Science & Technology
Physical Sciences
Technology
Chemistry, Physical
Engineering, Environmental
Engineering, Chemical
Chemistry
Engineering
Pdln catalysts
Pdln intermetallics
Nanoparticles
Methanol synthesis
CO2 hydrogenation
In2O3
LIQUID-PHASE METHANOL
STEAM REFORMING CATALYSTS
CARBON-DIOXIDE
IN-SITU
SUPPORTED PALLADIUM
SURFACE-PROPERTIES
ACTIVE-SITE
CU/ZNO
OXIDE
GA
Publication Status
Published
Date Publish Online
2017-07-25