Premium
Fundamental Insights from a Single‐Crystal Sodium Iridate Battery
Author(s) -
Tepavcevic Sanja,
Zheng Hong,
Hinks David G.,
Key Baris,
Ward Logan,
Lu Zhi,
Stoumpos Costas,
Ren Yang,
Freeland John W.,
Wolverton Christopher,
Phillips Patrick,
Klie Robert,
Mitchell John F.,
Markovic Nenad M.
Publication year - 2020
Publication title -
advanced energy materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 10.08
H-Index - 220
eISSN - 1614-6840
pISSN - 1614-6832
DOI - 10.1002/aenm.201903128
Subject(s) - redox , materials science , battery (electricity) , electrochemistry , transition metal , chemical physics , phase transition , inert , oxide , single crystal , phase (matter) , nanotechnology , crystallite , electrode , crystal (programming language) , chemical engineering , crystallography , power (physics) , chemistry , condensed matter physics , thermodynamics , catalysis , computer science , physics , biochemistry , organic chemistry , engineering , programming language , metallurgy
Electrochemically driven chemical transformations play the key role in controlling storage of energy in chemical bonds and subsequent conversion to power electric vehicles and consumer electronics. The promise of coupling anionic oxygen redox with cationic redox to achieve a substantial increase in capacities has inspired research in a wide range of electrode materials. A key challenge is that these studies have focused on polycrystalline materials, where it is hard to perform precise structural determinations, especially related to the location of light atoms. Here a different approach is utilized and a highly ordered single crystal, Na 2− x IrO 3 is harnessed, to explore the role of defects and structural transformations in layered transition metal oxide materials on redox‐activity, capacity, reversibility, and stability. Within a combined experimental and theoretical framework, it is demonstrated that 1) it is possible to cycle Na 2− x IrO 3 , offering proof of principle for single‐crystal based batteries 2) structural phase transitions coincide with Ir 4+ /Ir 5+ redox couple with no evident contribution from anionic redox 3) strong irreversibility and capacity fade observed during cycling correlates with the Na + migration resulting in progressive growth of an electrochemically inert O3‐type NaIrO 3 phase.