Indirect Nanoplasmonic Hydrogen Sensing

Abstract

The critical role of hydrogen in the global energy transition and its hazardous na ture underscores the importance of developing efficient and reliable hydrogen sensing technologies. This thesis explores the advancement of a hydrogen sensing method using indirect Localized Surface Plasmon Resonance (LSPR), where we investigate the alloying properties of small metal nanoparticles by means of solid-state dewet ting. The results from this thesis project are divided into three key parts. (i) A proof-of-concept has been realized, showing that indirect LSPR can be used as a means of monitoring hydrogen concentrations, using Ag 140x20nm nanodisks cov ered with much smaller (few nanometers) hydride-forming P d nanoparticles. (ii) Building on the insights gathered from the previous part, alloying of P dAu through solid-state dewetting has been investigated to replace the P d nanoparticles, yielding more than a twofold increase in performance with comparison to (i) and 10 times faster kinetics than its bulk equivalent (i.e. P dAu in direct LSPR). And finally (iii), an attempt to make all depositions through the mask, which proved to be unsuc cessful and suggests using a hard sacrificial mask instead of the soft PMMA-based one used in this work. Overall, this thesis highlights the promising potential of indirect LSPR for hydrogen sensing, offering a foundation for future research and technological development in this field.