Oxygen vacancies enabled hierarchical SnO2 for highly sensitive Cl2 detection at room temperature

Chlorine (Cl 2 ) is a highly hazardous and corrosive substance that can cause severe respiratory problems and skin burns in humans at low doses. The effective detection of Cl 2 has become critical for protecting both the ecological environment and public health. Herein, the oxygen vacancy-abundant SnO 2 were synthesized using SnS as template followed by the calcination method. The resultant SnO 2 -800 sensor exhibits improved sensing response to Cl 2 (about 205–10 ppm) at room temperature, together with a trace detection limit of 100 ppb. Such excellent sensing properties could be assigned to several reasons including the unique cross-linked structure, the appropriate amount of grain boundaries, and especially sufficient oxygen vacancies. The XPS, GC-MS techniques and DFT theoretical calculation were combined used to detailly investigate the sensing mechanism. This work might shed light on the rational design of high-performance sensing materials via defect engineering.