10-millisecond flash creates molybdenum disulfide for sensitive gas sensing

Researchers from Hanyang University ERICA and the Korea Advanced Institute of Science and Technology (KAIST) have demonstrated a rapid synthesis method that uses a 10-millisecond pulse of intense light to create molybdenum disulfide flakes decorated with isolated platinum atoms. This experimental study, published in Advanced Materials, shows that the brief flash heating process can produce a material with significantly enhanced room-temperature sensitivity to nitrogen dioxide. The approach addresses a persistent challenge in gas sensor development, where conventional heating methods often cause catalyst metals to clump together or fail to preserve the reactive edges of the sensing material. By using flash thermal synthesis, the team successfully anchored individual metal atoms to the molybdenum disulfide surface in a single step, resulting in a chemiresistive sensor with a detection limit of 17.2 parts per billion.

Many gas sensors operate by detecting changes in a material’s electrical properties as gas molecules interact with its surface. Molybdenum disulfide is considered a promising material for this purpose due to its favorable electronic properties, but a significant portion of its surface is chemically inactive. The more reactive edges of the material, which are crucial for sensing, can be difficult to preserve during conventional heating processes. Additionally, when catalyst metals are added to enhance sensitivity, they often agglomerate into nanoparticles rather than remaining as individual atoms, which reduces their effectiveness.

The research was jointly led by Professor Il-Doo Kim from KAIST and Assistant Professor Dong-Ha Kim from Hanyang University-ERICA as co-corresponding authors, with Dr. Euichul Shin from KAIST serving as the first author. The team utilized flash thermal synthesis, a technique driven by intense-pulsed light, to convert a molybdenum-containing precursor into thin molybdenum disulfide flakes. A single 10-millisecond pulse heated the material to temperatures as high as 1,811 degrees Celsius, followed by rapid cooling in ambient air. This extreme thermal shock allowed the researchers to incorporate platinum, iridium, or gold atoms into the material during the same synthesis step, avoiding the need for prolonged furnace treatments.

The brief, intense heating process played a critical role in the material’s final structure. It helped limit the growth of large flakes and kept the added metal atoms dispersed across the molybdenum disulfide surface rather than forming agglomerated metal nanoparticles. In comparative tests, the flash-made molybdenum disulfide produced a response to 5 parts per million of nitrogen dioxide that was 23.6 times stronger than material made by a conventional solvothermal method.

Adding 1.2 weight percent platinum to the molybdenum disulfide further boosted the sensor’s performance. The platinum-enhanced material showed a 22.8-fold increase in response compared to the unmodified flash-made material. When exposed to 400 parts per billion of nitrogen dioxide at room temperature, the sensor response reached 100.8 percent.

The platinum-enhanced sensor demonstrated a high level of sensitivity, detecting nitrogen dioxide at concentrations as low as 17.2 parts per billion. The material also exhibited selectivity for nitrogen dioxide compared with several other tested gases, which is essential for practical applications in complex environments. Stability tests showed that the sensor retained a stable response through 25 exposure-and-recovery cycles, indicating its potential for long-term use. After three weeks of storage in ambient air, the sensor’s response had declined by only 2.6 percent, suggesting good environmental stability.

Calculations performed by the researchers suggested that the isolated platinum atoms strengthen the interaction between the molybdenum disulfide material and nitrogen dioxide molecules. This enhanced interaction supports the measured improvement in sensing performance. By adjusting the active sites on the material, the approach offers a flexible way to prepare other functional nanomaterials. Dr. Kim stated that this strategy could help make sensitive and selective gas detection more practical, while also providing a route for developing new materials for various applications.

The synthesis used 8.6 kilojoules of electrical energy per gram of material. Because the light can illuminate a relatively broad area, the approach may offer a route toward more scalable production than methods requiring hours of heating in furnaces.

Despite these promising results, the study has certain limitations. The sensors were tested in a controlled laboratory setup, and real-world performance in varied outdoor conditions and commercial devices still needs evaluation. The current findings point to potential advances in room-temperature gas sensors for air-quality monitoring and industrial gas detection, but these remain pending further development and validation in field conditions.

The researchers suggest that the flash thermal synthesis method could be explored for catalysts used in clean-energy technologies and other advanced materials and energy conversion systems.

The study, titled “In Situ Single-Atom Decoration of Transition Metal Dichalcogenides by Millisecond Flash Thermal Synthesis Toward High Performance Room Temperature Chemiresistors,” was published in Advanced Materials on September 21, 2026. The paper was made available online on July 7, 2026.

Subject of Research: Flash thermal synthesis of platinum-decorated molybdenum disulfide for room-temperature nitrogen dioxide sensing

Article Title: Hanyang University ERICA scientists find that a 10-millisecond flash could help build more sensitive gas sensors

Article References: Hanyang University ERICA scientists find that a 10-millisecond flash could help build more sensitive gas sensors. Original publication (Bibliographic details unavailable.)

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Keywords: molybdenum disulfide, nitrogen dioxide, flash thermal synthesis, gas sensing, platinum atoms, room temperature, chemiresistors, Hanyang University, KAIST, Advanced Materials, nanomaterials, detection limit, single-atom decoration, air quality monitoring, electrical properties, solvothermal method, catalyst metals, energy efficiency, industrial gas detection, thermal shock