In situ X-ray diffraction investigation of the evolution of a nanocrystalline lithium-ion sieve from biogenic manganese oxide
その場X線回折による生物起源マンガン酸化物からナノサイズのリチウムイオン篩いの生成過程の研究
Yu, Q.; 笹木 圭子*
Yu, Q.; Sasaki, Keiko*
Microbial catalysis, a primary pathway for the generation of Mn oxides in most natural environments, provides potential to fabricate new materials. A microtube-type lithium manganese oxide (LMO-MT) was synthesized through a solid-state transformation using Mn-oxidizing fungus, Paraconiothyrium sp. WL-2. Compared with abiotic precursors, the lithium-ion sieve microtube (HMO-MT) showed better performance for Li+ recovery. In order to clarify the formation process of LMO-MTs, in situ high-temperature X-ray diffraction was used to compare with three synthetic references. The effects of calcination temperature on crystal phase, composition, particle size and lattice parameters of the LMO-MTs were systematically discussed. It was found that the poorly crystalline structure of biogenic precursor as well as high content of organic matter facilitated the formation of highly crystalline LMO-MTs at low temperature. The unique structural properties of LMO-MTs, including high crystallinity and small lattice constant, are attributed to the high Li sorption capacity of HMO-MTs.