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arXiv · 2312.04378

Operando pair distribution function analysis of nanocrystalline functional materials: the case of $\mathrm{TiO_{2}}$-bronze nanocrystals in Li-ion battery electrodes

Martin Aaskov Karlsen·Jonas Billet·Songsheng Tao·Isabel Van Driessche·Simon J. L. Billinge·Dorthe B. Ravnsbæk
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Abstract

Structural modelling of $operando$ pair distribution function (PDF) data of functional materials can be highly complex. To aid the understanding of complex operando PDF data, we here demonstrate a toolbox for PDF analysis. The tools include the structureMining, similarityMapping, nmfMapping apps available through the online service 'PDF in the cloud' (PDFitc, www.pdfitc.org), as well as noise-filtering using principal component analysis (PCA). The tools are applied to both ex situ and operando PDF data for 3 nm $\mathrm{TiO_{2}}$-bronze nanocrystals, which function as the active electrode material in a Li-ion battery. The tools enable structural modelling of the ex situ and operando PDF data, revealing two pristine $\mathrm{TiO_{2}}$ phases (bronze and anatase) and two lithiated $\mathrm{Li_{x}TiO_{2}}$ phases (lithiated versions of bronze and anatase), and the phase evolution during Galvanostatic cycling is characterized.

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Martin Aaskov Karlsen, Jonas Billet, Songsheng Tao, Isabel Van Driessche, Simon J. L. Billinge, Dorthe B. Ravnsbæk. 2023-12-07. Operando pair distribution function analysis of nanocrystalline functional materials: the case of $\mathrm{TiO_{2}}$-bronze nanocrystals in Li-ion battery electrodes. https://arxiv.org/abs/2312.04378

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