HEFEI, April 12 (Reporter Ding Yiming) - Recently, a research team led by Professor Chen Chilai from the Institute of Intelligent Materials, Hefei Institutes of Physical Science, Chinese Academy of Sciences, including researcher Wang Han, made a breakthrough in the field of deep-sea detection. Building upon previous deep-sea mass spectrometry research, they have increased the sensitivity of methane detection in water by over 500 times, reaching the level of background methane detection in oceans and lakes. This achievement marks a significant leap from monitoring anomalous methane dissolution events to long-term background methane monitoring.
Methane, the second-largest greenhouse gas after carbon dioxide, plays a crucial role in global climate change. Approximately 53% of methane emissions globally come from aquatic ecosystems such as oceans and lakes. Therefore, accurately monitoring the flux of methane from oceans to the atmosphere is of paramount importance. Additionally, methane is a primary component of natural gas hydrates, a novel clean energy source considered one of the most promising energy sources of the 21st century. Hence, monitoring methane in oceans holds significant value for ocean environmental awareness, identification of methane anomaly regions, marine energy exploration, and oceanographic research.
Due to the low concentration and high variability of methane in oceans, there is currently limited data on dissolved methane in oceans, leading to considerable uncertainty in estimating methane fluxes. Deep-sea mass spectrometers are crucial marine equipment for rapid detection of dissolved gases. However, due to their limited detection sensitivity, they can only detect specific regions or anomalous events.
In 2023, the research team led by Professor Chen Chilai successfully developed the "SmartMicro" deep-sea mass spectrometer and conducted multiple successful sea trials in a certain area of the South China Sea, obtaining vital dissolved gas information along ocean profiles. Building upon previous work, to further enhance detection sensitivity, the team addressed issues such as high sample gas content and limited space in the detection instrument. They developed a small-volume, low-power online water removal system and optimized the gas inlet design. These improvements were successfully integrated into the deep-sea mass spectrometer. While maintaining the high permeation flux of the target detection gas, this enhancement increased the vacuum degree of the mass spectrometer by over two orders of magnitude, resulting in a sensitivity increase of over 500 times for methane detection. This achievement brings the detection sensitivity of methane in deep-sea and lake water to the level of background signals, holding the promise of achieving indiscriminate monitoring of dissolved methane in oceans. This advancement will provide an important technical foundation for further methane flux calculations, global climate research, and cold seep discoveries.
