Authors
Kim, Sanghyeon; Yin, Liang; Bak, Seongmin; Fister, Timothy; Park, Haesun; Parajuli, Prakash; Gim, Jihyeon; Yang, Zhenzhen; Klie, Robert ; Zapol, Peter; Du, Yonghua ; Lapidus, Saul; Vaughey, John
Abstract
Calcium-ion batteries (CIBs) are a promising alternative to lithium-ion batteries (LIBs) due to the low redox potential of calcium metal and high abundance of calcium compounds. Due to its layered structure, alpha-MoO3 is regarded as a promising cathode host lattice. While studies have reported that alpha-MoO3 can reversibly intercalate Ca ions, limited electrochemical activity has been noted, and its reaction mechanism remains unclear. Here, we re-examine Ca insertion into alpha-MoO3 nanoparticles with a goal to improve reaction kinetics and clarify the storage mechanism. The alpha-MoO3 electrodes demonstrated a specific capacity of 165 mA h g(-1) centered near 2.7 V vs Ca2+/Ca, stable long-term cycling, and good rate performance at room temperature. This work demonstrates that, under the correct conditions, layered oxides can be a promising host material for CIBs and renews prospects for CIBs.