@article{7af59d9f2ab84777a0718b38bc1f80de,
title = "Peroxo Species Formed in the Bulk of Silicate Cathodes",
abstract = "Oxygen redox in Li-rich oxides may boost the energy density of lithium-ion batteries by incorporating oxygen chemistry in solid cathodes. However, oxygen redox in the bulk usually entangles with voltage hysteresis and oxygen release, resulting in a prolonged controversy in literature on oxygen transformation. Here, we report spectroscopic evidence of peroxo species formed and confined in silicate cathodes amid oxygen redox at high voltage, accompanied by Co2+/Co3+ redox dominant at low voltage. First-principles calculations reveal that localized electrons on dangling oxygen drive the O-O dimerization. The covalence between the binding cation and the O-O dimer determines the degree of electron transfer in oxygen transformation. Dimerization induces irreversible structural distortion and slow kinetics. But peroxo formation can minimize the voltage drop and volume expansion in cumulative cationic and anionic redox. These findings offer insights into oxygen redox in the bulk for the rational design of high-energy-density cathodes.",
keywords = "X-ray spectroscopy, ab initio calculations, lithium-ion batteries, oxygen redox, peroxo formation",
author = "Zhenlian Chen and Bjoern Schwarz and Xianhui Zhang and Wenqiang Du and Lirong Zheng and Ailing Tian and Ying Zhang and Zhiyong Zhang and Zeng, {Xiao Cheng} and Zhifeng Zhang and Liyuan Huai and Jinlei Wu and Helmut Ehrenberg and Deyu Wang and Jun Li",
note = "Funding Information: NIMTE group acknowledges supports by National R&D Program of China (2018YFB0704300, 2018YFB0704302), National Natural Science Foundation of China (21805297, 51802323, 11227902), Zhejiang Natural Science Foundation for Young Scholar (LQ18E020004) and is grateful for synchrotron beamlines 1W1B and 4B7B at Beijing Synchrotron Radiation Facility and beamline 02B02 at Shanghai Synchrotron Radiation Facility. Z.C. thanks visiting program by CSC. KIT group thanks CELLS-ALBA (Barcelona, Spain) for synchrotron beam time at BL04-MSPD beamline and is grateful for parts of this research at beamlines P02.1 and P64 at PETRAIII/DESY (Hamburg, Germany). This work contributes to the research performed at Centre for Electrochemical Energy Storage Ulm-Karlsruhe. We acknowledge support by the KIT-Publication Fund of the Karlsruhe Institute of Technology. Open access funding enabled and organized by Projekt DEAL. Publisher Copyright: {\textcopyright} 2021 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH",
year = "2021",
month = apr,
day = "26",
doi = "10.1002/anie.202100730",
language = "English (US)",
volume = "60",
pages = "10056--10063",
journal = "Angewandte Chemie - International Edition",
issn = "1433-7851",
publisher = "John Wiley and Sons Ltd",
number = "18",
}