고에너지 볼 밀링 공정을 이용한 ZnO 나노 입자의 H2S 가스 감지 성능 향상

Enhanced of H₂S Gas Sensing Performance of ZnO Nanoparticles via High-Energy Ball Milling Process

Hydrogen sulfide (H2S) gas is known to be hazardous, causing serious harm to humans and the environment; therefore, the development of sensor materials and devices is necessary. This study explored the use of Zinc Oxide (ZnO) nanoparticles, synthesized via high-energy ball milling, to improve H2S gas detection performance. Characterization analyses-such as scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy-confirmed that uniformly pulverized ZnO nanoparticles with the desired material properties were formed. The gas sensing results indicated that the pulverized ZnO exhibited improved H2S detection properties compared to pristine ZnO powders. Based on the evaluation of sensing characteristics within the range of 150°C to 300°C, the highest sensitivity to H2S gas was observed at 250°C, with the high-energy ball-milled ZnO nanoparticles showing a response of 15.72. Additionally, when gas sensing characteristics were evaluated at the same concentration for NH3, C₆H₆, C₇H₈, H2, and C2H₅OH, the sensor demonstrated superior selectivity for H2S compared to the other gases. The improved H2S detection performance is attributed to the increased surface area resulting from the high-energy ball milling process, which further reduced the size of ZnO particles and introduced defects on their surface. These factors enhanced the interaction between the gas molecules and the sensor material, leading to improved resistance modulation, especially in the presence of H2S gas. Overall, this study demonstrated the potential of high-energy ball milling as an effective method to significantly improve the gas sensing properties of nanosized materials.