Ultrafast Photothermal-Shock-Driven Multimetallic Exsolution for Artificial Olfaction of Sulfur Compounds Detection

Abstract

Exsolution-driven metal catalysts have emerged as promising candidates for artificial olfaction applications, offering enhanced sensing capability through catalytic activity and stability. However, precise control over multimetallic exsolution and its impact on gas selectivity remains underexplored. Herein, selective and stable sensors targeting sulfur-containing compounds-methyl mercaptan (CH3SH), dimethyl sulfide (DMS), and hydrogen sulfide (H2S)-based on exsolved multimetallic catalysts supported on ZnO are presented. A metal-organic framework-derived porous ZnO is employed as the exsolution host, while intense pulsed light (IPL) processing enables ultrafast activation method to induce Pt, Pd, and Ru nanoparticle emergence. Unlike conventional annealing, IPL enables temperature spikes exceeding 800 degrees C within milliseconds, minimizing bulk diffusion while promoting uniform nanoparticle dispersion. Structural and compositional analyses confirm enhanced catalyst stability, oxygen vacancy formation, and catalytic reactivity due to multimetallic exsolution. Gas sensing measurements show that PtPdRu-ZnO IPL exhibits the highest response to DMS, Pt-ZnO IPL to H2S, and PtPd-ZnO IPL to CH3SH. This selectivity is attributed to the catalytic synergy optimizing gas adsorption and reaction kinetics. Machine learning-assisted classification and regression models validate the sensing performance, achieving near-perfect gas identification and concentration prediction. This IPL-driven exsolution strategy offers a promising route toward high-performance artificial olfaction systems.