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arXiv · 2401.11743

Compton scattering study of strong orbital delocalization in a LiNiO$_2$ cathode

Veenavee Nipunika Kothalawala·Kosuke Suzuki·Johannes Nokelainen·Arttu Hyvönen·Ilja Makkonen·Bernardo Barbiellini·Hasnain Hafiz·Pekka Tynjälä·Petteri Laine·Juho Välikangas·Tao Hu·Ulla Lassi·Kodai Takano·Naruki Tsuji·Yosuke Amada·Assa Aravindh Sasikala Devi·Matti Alatalo·Yoshiharu Sakurai·Hiroshi Sakurai·Arun Bansil
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Abstract

Cobalt is used in Li-ion batteries, but it is expensive and could be replaced by nickel to deliver better performance at a lower cost. With this motivation, we discuss how the character of redox orbitals of LiNiO$_2$ can be ascertained through x-ray Compton scattering measurements combined with parallel first-principles simulations. Our analysis reveals the nature of hole states in Li-doped NiO resulting from the hybridization of O 2$p$ and Ni 3$d$ orbitals. Our study also gives insight into the ferromagnetic ground state and provides a pathway toward the rational design of next-generation battery materials.

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Veenavee Nipunika Kothalawala, Kosuke Suzuki, Johannes Nokelainen, Arttu Hyvönen, Ilja Makkonen, Bernardo Barbiellini, Hasnain Hafiz, Pekka Tynjälä, Petteri Laine, Juho Välikangas, Tao Hu, Ulla Lassi, Kodai Takano, Naruki Tsuji, Yosuke Amada, Assa Aravindh Sasikala Devi, Matti Alatalo, Yoshiharu Sakurai, Hiroshi Sakurai, Arun Bansil. 2024-01-22. Compton scattering study of strong orbital delocalization in a LiNiO$_2$ cathode. https://doi.org/10.1103/physrevb.109.035139

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