The Research and Development of a Prototype Instrument for Low Concentration Ammonia Detection in Indoor Environment

• Main Authors: Chang, Chuan-Peng, 張顓鵬
• Other Authors: Lu, Chia-Tung
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/wqv8f7

碩士 === 國立臺灣師範大學 === 化學系 === 106 === In this study, we’ve combined Arduino with the ammonia sensor unit, which provided by NCTU Department of Photonics Institute of OE Engineering to constructed a low-cost portable environment ammonia sensing device for analyzed ambient ammonia concentration around the school toilet, and built an ammonia concentration generating system as the ammonia source in the laboratory. The ammonia sensor unit used Organic semiconductor as key material for sensing ammonia. When the reduction gas contacted with the sensor unit. The decrease of background current caused by the absorption of the reduction gas, then computing the concentration of ammonia by the variety of background current. The establishment of the prototype was mainly divided into the structure part and gas pipeline part. Controlling the solenoid valve and saving the analog signals by Arduino. At the beginning of the experiment, the ammonia concentration generating system was built. The concentration of ammonia was adjusted by standard ammonia cylinder and the mass flow controller, aerated to H2O by impringer and measured the pH value, and estimated the concentration of ammonia formed by generating system. After the completion of the prototype assembly and correction and real sampling analysis. According to the state of sensor units, we could measure successfully the concentration of ammonia as low as 100 ppb, and up to 2500 ppb. Demonstrated that we could complete to analyze the indoor ammonia concentration in the low-cost and low- technical requirements. In the future, arise from the extension possibility and convenience of Arduino and modules, it can also realize the wireless transmission, achieve the real time large-scale environment monitor.