Our new paper in Applied Surface Science (Q1) "Conformal AlN-Derived Interphases Grown by Atomic Layer Deposition for Mitigating Interfacial Degradation of Silicon Anodes in Li-ion Batteries"

Silicon anodes suffer from severe interfacial degradation during repeated lithiation and delithiation, limiting their long-term electrochemical stability. In this work, conformal AlN-derived interphases were constructed on porous silicon electrodes by atomic layer deposition (ALD) to investigate their interfacial evolution and electrochemical behavior. Structural characterization confirmed the formation of a conformal coating layer. Depth-resolved X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) revealed that the deposited layer evolved into an Al/O-rich outer region and an AlN-rich inner region after exposure to ambient atmosphere. The optimized 50×AlN@Si electrode delivered 1273 mAh g⁻¹ after 300 cycles at 0.5C, compared with 658 mAh g⁻¹ for the pristine Si electrode. Control experiments using AlN-coated Cu electrodes confirmed that the deposited AlN layer contributed negligibly to reversible lithium storage, indicating that the improved electrochemical performance originated from enhanced interfacial stability. Post-cycling XPS and ToF-SIMS analyses further revealed the persistence of Al-containing interfacial species together with LiF- and Li_xSi_yO_z-rich reaction products. These findings establish a direct correlation between interphase evolution and electrochemical stability, providing design principles for artificial interphase engineering of silicon anodes.

https://www.sciencedirect.com/science/article/pii/S0169433226026036