Researchers from the French National Centre for Scientific Research (CNRS) and Sorbonne University have developed an advanced method for measuring the dynamics of fluids and confined systems, which could have significant implications for the energy sector. The team, led by Suzanne Lafon and Patrick Judeinstein, presented their findings in a recent study published in the Journal of Magnetic Resonance.
The study focuses on a technique called Stray Field Nuclear Magnetic Resonance (NMR), which provides a non-destructive way to measure the self-diffusion coefficients of various species. These coefficients are crucial for understanding transport properties in fluids and confined systems, which are relevant to a wide range of applications, including energy storage and membrane-based separation processes.
Traditionally, pulsed field gradient NMR (PFG-NMR) has been used for these measurements, but its ability to capture fast dynamics is limited. The researchers addressed this limitation by developing a robust and versatile methodology based on diffusion NMR in a permanent magnetic field gradient, also known as STRAFI. This approach allows for diffusion measurements over a broader temporal window, from a few hundred microseconds to several tens of seconds.
The researchers designed a specific experimental setup, optimized pulse sequences, and rigorous data analysis methods to accurately extract self-diffusion coefficients for a broad range of nuclei. They demonstrated the capabilities of their approach through various applications, including the study of concentrated electrolytes using less common nuclei and the characterization of micrometre-scale porosity in membranes.
For the energy sector, this advanced NMR technique could be particularly useful in the development and optimization of energy storage systems, such as batteries and supercapacitors. Understanding the transport properties of electrolytes and the porosity of membranes is crucial for improving the performance and efficiency of these devices. Additionally, the technique could be applied to the study of geological formations for enhanced oil recovery and geological carbon storage.
In summary, the researchers have developed a powerful and versatile method for measuring the dynamics of fluids and confined systems using STRAFI NMR. This technique offers a complementary approach to traditional PFG-NMR, enabling accurate diffusion measurements over an extended temporal window. The practical applications of this research are significant for the energy sector, particularly in the development of advanced energy storage systems and the study of geological formations.
Source: Lafon, S., Vedel, J., Teynier, C., Raj, M. D., Wzietek, P., Zeghal, M., & Judeinstein, P. (2023). Stray Field NMR: a powerful method to measure dynamics at the millisecond scale. Journal of Magnetic Resonance, 344, 107205.
This article is based on research available at arXiv.