| 학회 | 한국재료학회 |
| 학술대회 | 2021년 가을 (11/24 ~ 11/26, 경주 라한호텔) |
| 권호 | 27권 2호 |
| 발표분야 | 특별심포지엄 2. 환경 센서 소자 및 소재 연구 동향 심포지엄-오거나이저: 류학기(아주대) |
| 제목 | A room temperature NH3 sensor using copper halide film |
| 초록 | Ammonia (NH3), commonly found in refrigerants, cleaning products, and fertilizers, is a gas that has many toxic effects on humans and the environment. NH3 is also a tracer for food freshness evaluation and a breath marker for cirrhosis, hepatic encephalitic, or renal failure, as it is found in spoiled meat, poultry, and fish as well as in exhaled breath of humans with impaired liver and kidney. Thus, there has been lots of attention regarding sensors detecting NH3. As NH3 sensors, metal oxide semiconductors, conductive polymers, and graphene-derivatives with high miniaturization potential and low production cost have been extensively explored; however, such sensors have been limited to practical use due to their poor selectivity, sluggish recovery kinetics (even irreversible operation), and low sensitivity. CuBr, an ionic conductor with Cu+ as charge carrier, has a high potential as NH3 sensors because of its exclusive selectivity to NH3 and reversible operation even at room temperature. The NH3 sensing properties of CuBr have been firstly reported by the thin film prepared by sputtering. While this film demonstrated potential for NH3 detection, its response (resistance ratio) was too low to detect ppb level NH3 due to the dense and thick film structure. As the gas sensing characteristics are highly dependent upon the morphology and surface reaction of the sensing film, higher NH3 responses could be achieved if the film becomes porous. However, a proper method to fabricate porous CuBr films has been rarely reported so far. Herein, I suggest novel strategies of preparing porous CuBr films via flame-spray pyrolysis and subsequent bromination, thermal evaporation deposition of CuBr powders, and solution oxidation of sputtering-made Cu film. The sensors showed the highest NH3 response among the ones reported in the literature, and hence enabled to monitor ppb-level NH3. As heating is not required, such sensors are really ideal for integration into portable and flexible devices without extra complement system design. Therefore, the sensors in the present work will provide the best chance of realizing flexible and even wearable NH3 detectors that can be used for emerging applications including air quality monitoring, food freshness assessment, and breath analysis for disease diagnosis. |
| 저자 | 윤지욱 |
| 소속 | 전북대 |
| 키워드 | Gas sensors; CuBr; porous film; NH<SUB>3</SUB>; selectivity |
