Strain-engineered active site migration and machine learning-assisted NO2 recognition in UV-activated Cs-doped WO3-x nanosheets with operando mechanistic insights

Pristine metal oxide gas sensors often suffer from poor selectivity and limited polarizability. The objective of this work is to overcome these bottlenecks by developing an advanced material tailored specifically for highly sensitive and intelligent NO 2 sensing applications. Consequently, oxygen vacancy-rich 2D ultrathin Cs-doped WO 3-x nanosheets were synthesized via a solvothermal method. KPFM, UPS, and TAS confirmed that optimal Cs doping (0.08 mol%) optimizes the surface work function and drastically prolongs the photo-generated carrier lifetime (