Conductive LaCeNb6O18 with a Very Open A‐Site‐Cation‐Deficient Perovskite Structure: A Fast‐ and Stable‐Charging Li+‐Storage Anode Compound in a Wide Temperature Range. Issue 29 (16th June 2022)

• Record Type: Journal Article
• Authors: Wang, Wenze; Zhang, Qian; Jiang, Tian; Li, Songjie; Gao, Jiazhe; Liu, Xuehua; Lin, Chunfu
• Is Part Of: Advanced energy materials. Volume 12:Issue 29(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-06-16
• Subjects: cation deficient perovskites -- fast charging -- high‐temperature operation -- LaCeNb 6O 18 -- low strain, stable charging; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.202200656
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract: Li4 Ti5 O12 (LTO) is the most famous Li + ‐storage anode material with fast‐ and stable‐charging capability, but suffers from several disadvantages, such as poor electron conduction, low energy density, and disappointing high‐temperature performance. Here, LaCeNb6 O18 (LCNO) micrometer‐sized particles are explored as a fast‐ and stable‐charging anode material superior to LTO sub‐micrometer‐sized particles in terms of the working potential, rate capability, and high‐temperature performance. The conductive Ce 3+ and Nb 5+ ↔ Nb 3+ reactions in LCNO, respectively, enable its significantly larger electronic conductivity and lower working potential than those of LTO. LCNO owns a very open A‐site‐cation‐deficient perovskite structure, in which (vacancy/La/Ce)O12 layers with electrochemical inactivity and superior volume‐buffering capability locate between active NbO6 layers, leading to not only fast Li + diffusivity but also low‐ and negative‐strain behavior at different temperatures. At 25 ° C, LCNO exhibits higher rate capability (50 vs 0.1 C capacity ratio of 67.9%) than that of LTO, and excellent cyclability. At 60 ° C, LCNO maintains excellent cyclability, and achieves larger reversible capacity and even higher rate capability, whereas the high temperature lowers all the electrochemical properties of LTO. Therefore, LCNO holds great promise for fast‐ and stable‐charging applications in a wide temperature range, even when its particle sizes are on the order of micrometers. Abstract : Conductive LaCeNb6 O18 with a very open A‐site‐cation‐deficient perovskite structure is explored as a fast‐ and stable‐charging anode superior to Li4 Ti5 O12 in terms of the working potential, rate capability, and high‐temperature performance. LaCeNb6 O18 holds great promise for fast‐ and stable‐charging applications in a wide temperature range (especially at high temperatures), even when its particle sizes are on the order of micrometers.