Pt atomic cluster-decorated Fe ₂ (MoO ₄ ) ₃ hollow microspheres for detecting sub-parts-per-million xylene prepared by the atomic layer deposition method

Xylene, a volatile organic compound that is widely used in industrial processes, can pose significant health risks when present in ambient air. Accurate detection of xylene at low concentrations is crucial for environmental monitoring and industrial safety but remains challenging. This study employed a novel Pt atomic cluster (0.01%-1.5% weight percentage)-decorated Fe₂(MoO₄)₃ hollow microsphere sensor (Pt-FMO) using the atomic layer deposition method. Chemical and structural analyses confirmed the presence of isolated Pt atoms and clusters. Sensing performance studies revealed that 0.2% Pt-FMO exhibited a 47-fold increase in the gas response to xylene at 100 °C; moreover, it demonstrated rapid response and recovery time, an ultralow detection limit at sub-parts-per-million levels, good selectivity, and long-term stability. The high surface-to-volume ratio of the Pt atomic clusters significantly modified the surface chemical environment by increasing the adsorbed oxygen species while preserving surface morphology. Additionally, the Pt cluster catalyzed xylene oxidation, and the non-aggregated FMO hollow microspheres chemisorbed more oxygen molecules during the sensing process. The synergistic effect of Pt atomic clusters and FMO hollow microspheres makes this sensor a promising candidate for applications in environmental and industrial gas monitoring.