In-doped SnS2 Induced S-Vacancies for Ammonia-Sensitive Sensors

In this study, In-doped SnS 2 nanostructures were synthesized by a one-step hydrothermal method. Characterization results demonstrated that S vacancies were successfully constructed in the synthesized material. Samples doped with different masses of indium were prepared. Among them, the In/V s2 -SnS 2 sample with moderate sulfur vacancy content the In/V s2 -SnS 2 showed the best ammonia detection response (500 ppm) at room temperature, and the peak response reached 2392. Moreover, the sensor exhibited a response/recovery time of 37.5s/3.3s. The adsorption energies of ammonia on the pure phase SnS 2 surface and S vacancies were determined by the first principle DFT calculations. The theoretical analysis agreed well with the experimental results, suggesting that the S vacancies provided more active sites for effective adsorption, favoring the sensitive detection of ammonia molecules. The proposed study demonstrates that In-doping created S vacancies in SnS 2 , which is promising for gas sensitization, laying the foundation for high-performance room-temperature gas sensors.