Pd-C catalytic thin films prepared by magnetron sputtering for the decomposition of formic acid

Formic acid is an advantageous liquid organic hydrogen carrier. It is relatively nontoxic and can be synthesized by the reaction of CO2 with sustainable hydrogen or by biomass decompo-sition. As an alternative to more widely studied powdery catalysts, supported Pd-C catalytic thin films with control...

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Bibliographic Details
Authors: Arzac, G. M., Fernández Camacho, Asunción, Fortio Godinho, Vanda Cristina, Hufschmidt, Dirk, Jiménez de Haro, María del Carmen, Medrán, Beatriz, Montes Amorín, Olga
Format: article
Status:Published version
Publication Date:2021
Country:España
Institution:Universidad de Sevilla (US)
Repository:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/128829
Online Access:https://hdl.handle.net/11441/128829
https://doi.org/10.3390/nano11092326
Access Level:Open access
Keyword:Catalyst
Formic acid
Hydrogen
LOHC
Magnetron sputtering
Pd-C
Thin film
Description
Summary:Formic acid is an advantageous liquid organic hydrogen carrier. It is relatively nontoxic and can be synthesized by the reaction of CO2 with sustainable hydrogen or by biomass decompo-sition. As an alternative to more widely studied powdery catalysts, supported Pd-C catalytic thin films with controlled nanostructure and compositions were newly prepared in this work by mag-netron sputtering on structured supports and tested for the formic acid decomposition reaction. A two-magnetron configuration (carbon and tailored Pd-C targets) was used to achieve a reduction in Pd consumption and high catalyst surface roughness and dispersion by increasing the carbon con-tent. Activity and durability tests were carried out for the gas phase formic acid decomposition reaction on SiC foam monoliths coated with the Pd-C films and the effects of column width, surface roughness and thermal pre-reduction time were investigated. Activity of 5.04 molH2∙gPd−1∙h−1 and 92% selectivity to the dehydrogenation reaction were achieved at 300 °C for the catalyst with a lower column width and higher carbon content and surface roughness. It was also found that deactivation occurs when Pd is sintered due to the elimination of carbon and/or the segregation and agglomera-tion of Pd upon cycling. Magnetron sputtering deposition appears as a promising and scalable route for the one-step preparation of Pd-C catalytic films by overcoming the different deposition characteristics of Pd and C with an appropriate experimental design.