![]() This is the first reported attempt to synthesize lithium-rich antiperovskite compounds by RF magnetron sputtering. For Li 2OHCl in particular, it is expected that further optimization of the processing conditions will lead to a significant increase in Li + conductivity. Owing to the low phase purities of films deposited from both target types, the Li + conductivities were found to be on the order of 10 −8 S cm −1. While FT-IR results showed that O–H bonding was present in these films, a small volume fraction of an antiperovskite phase with identical lattice parameter to Li 2OHCl was only detected after heating the films to ∼100 ☌. Deposition of films with similar thicknesses from an Li 2OHCl powder target was also performed for comparison. Characterization by Fourier transform infrared spectroscopy (FT-IR) confirmed the absence of O–H bonding in the films, providing further evidence that the antiperovskite phase was Li 3OCl rather than Li 2OHCl. This antiperovskite phase decomposed into Li 2O and LiCl upon annealing at moderate temperatures. X-ray diffraction (XRD) experiments showed that reaction between the precursor phases occurred within the growing films to form a volume of antiperovskite phase with an identical lattice parameter to that predicted for cubic Li 3OCl. Measures were taken to minimize the presence of moisture at all stages of synthesis and characterization. In this report, we demonstrate the stabilization of a small volume fraction of antiperovskite phase with the characteristics expected for Li 3OCl in ∼0.5 to ∼1 μm films fabricated from a Li 2O + LiCl powder target by RF magnetron sputtering. Therefore, the likelihood of inadvertently forming the structurally similar thermodynamically stable hydroxide halide compound Li 2OHCl is very high. There are two key challenges associated with this synthesis: the thermodynamic instability of Li 3OCl at room temperature and its extreme hygroscopicity. Several attempts to synthesize Li 3OCl – a lithium-rich antiperovskite compound envisaged as a potential solid electrolyte material for lithium metal batteries – have been reported, but few have yielded convincing results. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |