Issue 1, 2018

Platinum for hydrogen sensing: surface and grain boundary scattering antagonistic effects in Pt@Au core–shell nanoparticle assemblies prepared using a Langmuir–Blodgett method

Abstract

Hydrogen resistive sensors are fabricated through the synthesis of a series of Pt@Au core–shell nanoparticles showing various Pt shell thicknesses. Resulting colloids are assembled as hexagonal close-packed 2D monolayers of various dimension characteristics using a simple Langmuir–Blodgett method. The fabricated sensors show attractive hydrogen sensing performances with reversible responses in extended sensing ranges, a good specificity towards H2, short response and recovery times… Sensing measurements and data analyses allow the demonstration of the associated sensing mechanisms. The dissociative chemisorption of H2 and O2 on the Pt surface through a Langmuir–Hinshelwood mechanism leads to the formation of chemisorbed hydrogen and hydroxyl groups. This surface nature change induces the modification of the scattering of the conduction electrons at both the grain surface and intercontacts, tuned by the extent of hydrogen and hydroxyl group coverages. In assemblies made of particles showing thin Pt shells, the predominance of the surface scattering described by the Fuchs–Sondheimer model accounts for the observed conductive responses as the number of involved grain boundaries is limited. In contrast, in assemblies made of particles with thick Pt shells, the scattering at the grain boundaries described by the Mayadas–Shatzkes model mostly contributes to the observed resistive responses. The sensor behavior is balanced by these two antagonistic effects.

Graphical abstract: Platinum for hydrogen sensing: surface and grain boundary scattering antagonistic effects in Pt@Au core–shell nanoparticle assemblies prepared using a Langmuir–Blodgett method

Supplementary files

Article information

Article type
Paper
Submitted
28 Sep 2017
Accepted
23 Nov 2017
First published
23 Nov 2017

Phys. Chem. Chem. Phys., 2018,20, 383-394

Platinum for hydrogen sensing: surface and grain boundary scattering antagonistic effects in Pt@Au core–shell nanoparticle assemblies prepared using a Langmuir–Blodgett method

K. Rajouâ, L. Baklouti and F. Favier, Phys. Chem. Chem. Phys., 2018, 20, 383 DOI: 10.1039/C7CP06645G

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements