High Resolution 3-Dimensional Chemical and Morphological Imaging of Single LixFePO4 Particles
In this study, soft X-ray tomography combined with ptychography, developed at beamline 220.127.116.11 at the Advanced Light Source (Berkeley, CA) is applied to assess the chemical and morphological consequences of electrochemical delithiation of aggregated nano-sized lithium iron phosphate (LiFePO4) plates (Figure 1). Our work provides quantitative analysis of oxidation states in 3 dimensions at the 10 nm scale. After segmentation, statistical analysis of the chemical phase for any given individual particle was achieved, and information was extracted of the particle interior. The ability to visualize the nanoscale chemical state distribution over functional volumes will revolutionize the study of energy storage materials and enable the design of optimized morphologies for the next generation of devices.
Figure 1. 3 dimensional chemical volume rendering of LixFePO4 crystals. Chemical phase information were extracted from 3 dimensional volumes collected at 708.25 eV and 710.25 eV. The red and blue areas indicate the highest content of LiFePO4 and FePO4, respectively.
1. D. A. Shapiro, Y.-S. Yu, T. Tyliszczak, J. Cabana, R. Celestre, W. Chao, K. Kaznatcheev, A. L. D. Kilcoyne, F. Maia, S. Marchesini, Y. S. Meng, T. Warwick, L. L. Yang, H. A. Padmore, Nat Photon 8, 765 (2014).