High-performance acetone gas sensor based on Pt–Zn2SnO4 hollow octahedra for diabetic diagnosis

Acetone in exhaled breath can be used as a biomarker for diabetes diagnosis, but its concentration is extremely low. Thus, a gas sensor with high sensitivity and a low detection limit (sub-ppm level) is vital in practical application. Here, ultrafine Pt nanoparticles were prepared and used to decorate the surface of Zn2SnO4 (ZTO) hollow octahedra for enhanced acetone gas-sensing performance towards breath analysis. The Pt nanoparticles were prepared by a simple wet chemical method, whereas the decoration on the surface of ZTO was conducted by mixing different amounts of Pt nanoparticles. The synergistic effect of the high catalytic activity of Pt nanoparticles and the large surface area of ZTO hollow octahedra endowed the fabricated sensor with excellent acetone-sensing performance at the optimum temperature of 350 °C. Compared with pristine ZTO, the 1 wt% Pt–ZTO device showed the best acetone sensing behaviour at 350 °C with an excellent selectivity, repeatability, and stability. It was able to detect acetone at ppb level, which was satisfactory for breath analysis in diabetes diagnosis. Notably, the 1 wt% Pt–ZTO sensor exhibited a 36.9-fold enhancement in response to acetone compared with the pristine ZTO. Moreover, the effect of Pt decoration on gas-sensing behaviours and the gas-sensing efficiency enhancement mechanism of ZTO hollow octahedra were discussed.