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arXiv · 2304.03482

Mending Cracks in Rutile TiO$_{2}$ with Electron Beam

Silu Guo·Hwanhui Yun·Sreejith Nair·Bharat Jalan·K. Andre Mkhoyan
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Abstract

Restructuring of rutile TiO$_{2}$ under electron beam irradiation driven by radiolysis was observed and analyzed using a combination of atomic-resolution imaging and electron energy loss spectroscopy (EELS) in scanning transmission electron microscopy (STEM). It was determined that a high-energy (80-300 keV) electron beam at high doses ($\gtrapprox 10^7 \ e/nm^2$) can constructively restructure rutile TiO$_{2}$ with an efficiency of $6\times 10^{-6}$. These observations were realized using rutile TiO$_{2}$ samples with atomically sharp nanometer-wide cracks. Based on atomic-resolution STEM imaging and quantitative EELS analysis, we propose a $"$ 2-step $"$ rolling model of the octahedral building blocks of the crystal to account for observed radiolysis-driven atomic migration.

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Silu Guo, Hwanhui Yun, Sreejith Nair, Bharat Jalan, K. Andre Mkhoyan. 2023-04-07. Mending Cracks in Rutile TiO$_{2}$ with Electron Beam. https://arxiv.org/abs/2304.03482

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