[17p-D221-1~13] 9.2 Nanoparticles, Nanowires and Nanosheets

▼ [17p-D221-5] Gas Sensing Mechanism in Au@SnO₂ Nanoparticle-Based Chemiresistor Studied by in-situ Surface-Enhanced Raman Spectroscopy

〇(P)Haoming Bao¹, Kenta Motobayashi¹, Katsuyoshi Ikeda¹ (1.Nagoya Institute of Technology)

Keywords:In-situ Surface-Enhanced Raman Spectroscopy (SERS), Au@SnO2 Nanoparticle-based Gas Sensing, Mars-Van-Krevelen Mechanism

Understanding the mechanisms can provide a fundamental guideline for designing higher-performance gas sensors. However, the mechanisms are still under controversy between Langmuir-Hinshelwood and Mars-van Krevelen (MvK) models. This work constructs a sensitive in-situ surface-enhanced Raman spectroscopy (SERS) tracing platform based on Au@SnO₂ NPs (with SERS and gas sensing dual functions) for tracing the ethanol gas sensing. The observed evolutions of Raman bands [including the weakened band associated with bridging OVs, stable band related to the in-plane OVs, and some strengthened bands of IR-active modes] in the in-situ SERS suggest that the sensing follows a Mars-Van-Krevelen (MvK) mechanism, in which the bridging lattice oxygen is selectively reacted to from oxygen vacancies (OVs). This work presents an in-situ tracking strategy for gas sensing and confirms the MvK mechanism in Au@SnO₂ NP-based gas sensing.