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СИНТЕЗ И ИОННАЯ ПРОВОДИМОСТЬ ТВЕРДЫХ ЭЛЕКТРОЛИТОВ НА ОСНОВЕ ФОСФАТА ЛИТИЯ-ТИТАНА
The processes occurring during the solid-state synthesis of germanium-doped lithium titanium
phosphate have been studied. The formation of LiTi2 – xGex(PO4)3 has been shown to proceed through the
titanium pyrophosphate formation followed by its transformation into materials with the NASICON structure.
The process is completed at 1073 K. To produce ceramics with an optimal conductivity, annealing at
1173 K is required. Based on the results obtained, a two-stage synthesis procedure was developed. The highest
ionic conductivity (3.9 × 10–5 Ohm–1 cm–1 at 433 K) and the lowest activation energy (46 ± 1 kJ/mol) were
observed for LiTi2 – xGex(PO4)3 materials with a titanium substitution degree of 20–25% (x = 0.4–0.5). It can
be attributed to an optimal size of lithium transport channels.