Loading…
Subnanometric Pt clusters dispersed over Cs-doped TiO for CO upgrading low-temperature RWGS: mechanistic insights to guide an optimal catalyst design
The RWGS reaction is gathering momentum as an effective route for CO 2 valorisation and given its endothermic nature the challenge lies in the design of active low-temperature catalysts. Herein we have designed two catalysts based on subnanometric Pt clusters providing effective CO 2 conversion and,...
Saved in:
| Published in: | Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2024-01, Vol.12 (3), p.1779-1792 |
|---|---|
| Main Authors: | , , , , , , , , , , |
| Format: | Article |
| Language: | |
| Online Access: | Get full text |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | The RWGS reaction is gathering momentum as an effective route for CO
2
valorisation and given its endothermic nature the challenge lies in the design of active low-temperature catalysts. Herein we have designed two catalysts based on subnanometric Pt clusters providing effective CO
2
conversion and, more importantly, high CO selectivity in the low-temperature range. The impact of Cs as a dopant in the catalyst's formulation is crucial leading to full selectivity at 300 °C. The reaction mechanisms for the studied systems namely Pt/TiO
2
and PtCs/TiO
2
are significantly different due to the presence of the alkali promoter. The presence of Cs neutralises the hydroxide groups of the TiO
2
surface, changing the reaction pathway. The Pt/TiO
2
catalyst follows a redox mechanism where CO
2
dissociates to CO in the oxygen vacancies, and then these vacancies are recovered by the migration of H
2
by spill over phenomena. On the other hand, the Cs doped catalyst has two possible mechanism pathways: the (ii) formyl/acyl pathway, where -CHO species are formed and, depending on the reaction conditions, evolve to CO gas or oxygenated compounds, and (ii) frustrated Lewis pair (FLP) assisted CO
2
reduction route, in which the FLP induces the heterolytic dissociation of H
2
and the subsequent hydrogenation of CO
2
to CO. The latter route enabled by Cs-doping combined with the subnanometric Pt domains seems to be responsible for the excellent catalytic behaviour leading to fully selective low-temperature RWGS systems and thus unlocking new possibilities for less energy demanding CO
2
valorisation units based on RWGS.
Cs-doped Pt/TiO
2
advanced catalysts for CO
2
conversion
via
low-temperature RWGS: from
operando
and mechanistic study to real-catalyst design to combat global warming. |
|---|---|
| ISSN: | 2050-7488 2050-7496 |
| DOI: | 10.1039/d3ta05482a |