Novel piezo-controlled ATR-FTIR microspectroscopy for in-situ monitoring of electrochemical reaction in battery models

Attenuated total reflection Fourier transform infrared (ATR-FTIR) technique has become indispensable for surface-specific molecular analysis. At the Australian Synchrotron's Infrared Microspectroscopy (IRM) beamline, we have advanced this technique by developing a novel piezo-controlled ATR-FTIR device designed for in-situ monitoring of electrochemical reactions in battery models. This piezo-controlled ATR-FTIR system incorporates high-precision piezoelectric linear translation stages, enabling sub-micron positioning and a gentle approach to engage samples with step intervals as small as 50 nm. By capturing high-quality spectral data during charge–discharge cycles of zinc ion batteries (ZIBs) at a controlled 100 nm distance from the electrode surface, the system overcomes common spectral artifacts associated with traditional reflectance setups and provides genuine interfacial chemical information without disrupting ongoing reactions. Combining the unique ability to monitor interfacial chemistry with its precision and reproducibility, this piezo-controlled ATR-FTIR device expands the analytical potential of synchrotron-FTIR microspectroscopy, offering transformative insights into the formation of solid electrolyte interphase and solvation mechanisms. The applications in ZIBs demonstrated in this study highlight the capability of the piezo-controlled ATR-FTIR technique for understanding critical interfacial processes that underpin energy storage performance and catalysis research, setting a new standard for synchrotron-FTIR studies of dynamic interfacial phenomena. © 2025 The Author(s).