Facile strategy for screening and fabricating metal-organic framework-based sensors for highly sensitive detection of iodine gas
image: Chemically stable metal-organic frameworks with good affinity for iodine (including Zn(1,3-BDP), UiO-66, UiO-66-NH2, etc.) were computationally screened and drop-casted upon interdigitated electrodes to achieve highly sensitive electrical detection of iodine gas.
Credit: Nano Research, Tsinghua University Press
Radioactive iodine gas detection has significant applications in the nuclear industry, particularly in nuclear accident scenarios and nuclear fuel reprocessing facilities. Metal-organic frameworks (MOFs), owing to their high specific surface area, large pore volume and structurally tunable nature, hold great promise as sensing materials for the electrical detection of iodine gas, by combining with impedance spectroscopy techniques.
A team of material scientists led by Guangcun Shan from Beihang University in Beijing, China recently proposed a novel and feasible method for investigating sensing materials and strategies to fabricate high-performance iodine gas sensors. By integrating computational screening, material optimization and experimental fabrication, the research team successfully fabricated iodine sensors with high sensitivity, rapid response, and excellent cycling stability. This work offered an innovative solution for the detection of radioactive iodine gas in nuclear accident emergency monitoring and nuclear fuel reprocessing facilities.
The team published their research in Nano Research on June 23, 2025.
Chemically stable MOFs with good affinity for iodine (including Zn(1,3-BDP), UiO-66, UiO-66-NH2, etc.) were computationally screened and drop-casted upon interdigitated electrodes (IDEs). Upon exposure to I2 gas, a similar electrical response change occurred for all the IDE sensors, despite variations in impedance ratio. In particular, UiO-66-coated sensors exhibited an impedance ratio >103 times, while the modification of amino groups (-NH2) enhanced the sensitivity, exceeding 104 times for UiO-66-NH2, and was accompanied by a better iodine uptake. Notably, the sensors fabricated from Zn(1,3-BDP), which also contained nitrogen atoms, exhibited excellent comprehensive sensing performance, including high sensitivity (with impedance ratio achieving 1.4×106 times), good recyclability, rapid response speed (with an impedance change of 250 times within 3 minutes), low detection limit (about 29 times under 300 ppm I2 vapor at 25℃) and high anti-interference ability.
“We found that the adsorbed I2 introduced new states, especially band gap states into the density of states of pure MOF materials, which played a significant role in lowering the bandgap and enhancing the electrical conductivity,” emphasized Professor Guangcan Shan, corresponding author of the research work in the School of Instrumentation Science and Opto-electronics Engineering at Beihang University. Using density functional theory (DFT) calculations, the research team confirmed that iodine molecule adsorption significantly reduced the bandgap of the MOF material, thereby enhancing its electrical conductivity.
MOF-based sensors developed in this study also exhibited strong anti-interference capability. Under environment of pure air, ethanol and acetone at 70℃ for 1h, Zn(1,3-BDP)-based sensors exhibited the impedance ratio below ×1.5 times; after exposing to methanol and water, the impedance ratio was also lower than ×2.0 times. This made sensors well-suited for deployment in complex industrial environments.
Other contributors include Haoyi Tan from the School of Instrumentation Science and Opto-electronics Engineering at Beihang University in Beijing, China; and Hongbin Zhao from the Department of Materials Science and Engineering at City University of Hong Kong in Hong Kong, China.
The work was carried out at National Supercomputer Center in Tianjin, and the calculations were performed on Tianhe new generation supercomputer. This work was financially supported by the National Key R&D Program of China (No. 2016YFC1402504).
About the Authors
Dr. Guangcun SHAN received his PhD in Materials Science and Physics in 2013 from City University of Hong Kong. Afterwards he worked as a postdoctoral scientist at Max-Planck Institute in Germany and also at the University of Hong Kong. In 2016, he got promoted to be full professor at Beihang University. And he has been a visiting professor at Saarland University, Germany from 2016 to 2019 and in 2024.
In 2018, he received Hong Kong K.C. Wong Foundation sponsorship, and was awarded with the Outstanding Young Scientist Awards by the Chinese Materials Research Society (C-MRS) in recognition of outstanding achievement and potential in the fields of glassy alloys. In recent years, he has also received many prizes and honours, including National Powerful Young Scientist nomination Award 2021; China Industry-University-Research Cooperation Innovation Award and nomination of APEC Science Prize as China representative; IAAM Scientist Medal (2023); Technology Invention Award of the Chinese Society of Aeronautics and Astronautics in 2023.
His work was awarded the 3rd place prize as a supervisor for breaking the wall of radionuclide adsorption in FALLING WALLS Lab Beijing and the TOP10 award in the Green and Low-carbon Growth category of the Beijing Zhongguancun International Advanced Frontier S&T Competition.
His research interest is focused on 2D materials for flexible electronics and environmental remediation, smart sensors, AI for Science (AI4S) and robotics. Prof. Shan has authored over 120 refereed papers in prestigious journals such as Advanced Materials, Progress in Materials Science, npj Computational Materials, IEEE Transactions on Instrumentation & Measurement, Materials Today Physics, and Applied Materials Today. He is a council member of the Beijing Interdisciplinary Science Society and the Vice Chair of the Artificial Intelligence and Big Data Innovation League of National Universities of China.
For more information, please pay attention to his research homepage https://shi.buaa.edu.cn/gcshan/zh_CN/index.htm
About Nano Research
Nano Research is a peer-reviewed, open access, international and interdisciplinary research journal, sponsored by Tsinghua University and the Chinese Chemical Society, published by Tsinghua University Press on the platform SciOpen. It publishes original high-quality research and significant review articles on all aspects of nanoscience and nanotechnology, ranging from basic aspects of the science of nanoscale materials to practical applications of such materials. After 18 years of development, it has become one of the most influential academic journals in the nano field. Nano Research has published more than 1,000 papers every year from 2022, with its cumulative count surpassing 7,000 articles. In 2024 InCites Journal Citation Reports, its 2024 IF is 9.0 (8.7, 5 years), and it continues to be the Q1 area among the four subject classifications. Nano Research Award, established by Nano Research together with TUP and Springer Nature in 2013, and Nano Research Young Innovators (NR45) Awards, established by Nano Research in 2018, have become international academic awards with global influence.