Highly Sensitive and Selective Trimethylamine Sensor Using Yolk-shell Structured Mo-doped Co₃O₄ Spheres = Highly Sensitive and Selective Trimethylamine Sensor Using Yolk-shell Structured Mo-doped Co₃O₄ Spheres

다국어 초록 (Multilingual Abstract)

Pure and 0.5, 1, 2, 5, and 10 at% of Mo-doped Co₃O₄ yolk-shell spheres were synthesized by ultrasonic spray pyrolysis of droplets containing Co nitrate, ammonium molybdate, and sucrose and their gas sensing characteristics to 5 ppm trimethylamine (TMA), ethanol, p-xylene, toluene, ammonia, carbon monoxide, and benzene were measured at 225-325 ℃. The sensor using pure Co₃O₄ yolk-shell spheres showed the highest response to p-xylene and very low response to TMA at 250 ℃, while the doping of Mo into Co₃O₄ tended to increase the overall responses of gas sensors. In particular, the sensor using 5 at% Mo-doped Co₃O₄ yolk-shell spheres exhibited the high response to TMA with low cross-responses to other interfering gases. The high response and selectivity of Mo-doped Co₃O₄ yolkshell spheres to TMA are attributed to the electronic sensitization by higher valent Mo doping and acid-base interaction between TMA and Mo components.