The world’s first highly flexible and ultra-sensitive ammonia sensor based on a low-temperature synthesized copper bromide (CuBr) film, developed by the KIMS research team. Credit: Korea Institute of Materials Science (KIMS)
KIMS has developed the world’s first highly flexible and ultra-sensitive ammonia sensor technology, utilizing a low-temperature synthesized copper bromide film.
A research team from the Energy & Environmental Materials Research Division at the Korea Institute of Materials Science (KIMS), led by Dr. Jongwon Yoon, Dr. Jeongdae Kwon, and Dr. Yonghoon Kim, has developed the world’s first ammonia (NH₃) gas sensor using a copper bromide (CuBr) film. This sensor can be produced through a simple, low-temperature solution process, marking a major advancement in sensor technology.
The new CuBr-based sensor offers several key benefits: it is flexible, highly sensitive, highly selective, and cost-effective to manufacture. Ammonia sensors are critical for detecting airborne ammonia in a range of applications, including environmental monitoring, industrial safety, and medical diagnostics. The CuBr film’s electrical resistance changes significantly in the presence of ammonia, allowing it to detect even trace amounts of the gas with high accuracy.
Overcoming Conventional Limitations
In conventional methods, forming the copper bromide (CuBr) film required for the sensor necessitated a high-temperature vacuum process above 500°C. This posed challenges in applying it to flexible substrates, which are vulnerable to heat, and also led to high production costs.
Schematic illustration of the copper bromide (CuBr) film synthesis process. A two-dimensional copper nanosheet is formed on the substrate, followed by a solution-based process to synthesize the copper bromide film. Credit: Korea Institute of Materials Science (KIMS)
To address this issue, the research team developed a technique to form a two-dimensional copper nanosheet on a substrate at a temperature below 150°C without a vacuum process. They then synthesized the copper bromide film through a simple solution-based process. As a result, they successfully implemented an ammonia gas sensor on a plastic substrate.
High Sensitivity and Durability
This study successfully developed a highly sensitive sensor capable of detecting ammonia concentrations as low as one part per million (ppm) using a low-temperature solution-based process. This breakthrough significantly reduces manufacturing costs and offers potential applications in wearable sensors and diagnostic medical devices. Furthermore, experimental tests involving over 1,000 repeated bending cycles confirmed that the sensor maintained high performance and operated with stable functionality.
Dr. Jongwon Yoon, the lead researcher, stated, “The ammonia sensor developed through this study has great potential for expansion into flexible and wearable devices. It can be utilized in a wide range of applications, from indoor air quality monitoring to personal health management.”He further emphasized, “In particular, we expect that it could be applied as a disease diagnosis sensor by attaching it to the human body to analyze exhaled breath.”
Reference: “Low-temperature solution-processed flexible NH3 gas sensors based on porous CuBr films derived from 2D Cu nanosheets” by Juyoung Jin, Hyojin Bang, Seungyeon Kim, Hee Yun Yang, Sukang Bae, Seung Min Yu, Yonghun Kim, Jung-Dae Kwon, Hong Seung Kim, Tae-Wook Kim and Jongwon Yoon, 4 March 2025, Sensors and Actuators B: Chemical.
DOI: 10.1016/j.snb.2025.137567
The research was conducted in collaboration with Professor Tae-Wook Kim from Jeonbuk National University and Professor Hong Seung Kim from Korea Maritime & Ocean University. This study was supported by the Global TOP Project of the National Research Council of Science & Technology (NST), the Nano and Material Technology Development Program of the National Research Foundation of Korea (NRF), and fundamental projects of the Korea Institute of Materials Science (KIMS).