Effect of annealing temperature on the transparent lithium strontium lanthanum titanate thin films

Review on Synthesis and Properties of Lithium Lanthanum Titanate

“…Lanthanum oxide, La 2 O 3 , is hygroscopic and, when exposed to air, decomposes reversibly to lanthanum hydroxide, La(OH) 3 . Many authors employ a heat treatment at approximately 1000 • C for up to 12 h to the lanthanum oxide before weighing [7,59]. Moreover, similarly to the situation of the sol-gel method, excess Li 2 CO 3 is used to compensate the material losses through evaporation.…”

“…The inorganic (ceramic) electrolytes have very good ionic conductivity, occasionally comparable to the conductivity of the liquid organic electrolytes [5,6], good resistance to dendrite growth and better thermal stability than polymer conductors [7]; however, they tend to form high impedance contacts. There are approximately five categories of ceramic electrolytes: perovskites, super ionic conductors (LiSICON, NaSICON), sulphates and salts.…”

All‐Solid‐State Thin Film μ‐Batteries for Microelectronics

“… Influence of dopants on the conductivity: a) changes of lattice parameter as well as ionic conductivity of bulk Li 0.33+ x La 0.56− x Sr x TiO 3 after A‐site substitution of Sr (data from [159 ] ), b) changes of ionic conductivity of rf‐sputtered Li 0.33+ x La 0.56− x Sr x TiO 3 (data from [161 ] ), c) changes of bulk and grain boundary ionic conductivity at different concentration of Al 3+ , (data from [168 ] ), d) influence of B‐site substitution on the lattice parameters and ionic conductivities of Li 0.24 La 0.587 Ti 1‐ x Sn x O 3 and Li 0.24‐ x La 0.587 Ti 1‐ x Ta x O 3 (data from [ 162 ] ), e) conductivity of La (2/3) − x Li 3 x ⊡ (1/3) − 2 x TiO 3 at different Li + concentration and processing temperatures (data from 166 , 167 , 168 ] ), and f) conductivity of Li 0.5 La 0.5 TiO 4 thin‐film electrolytes deposited by PLD at various temperatures (data from 166 , 171 ] and [ 172 ] where PLD was used, and [176 ] where melt‐quench was used.) …”

“…The ionic conductivity of the as‐deposited Li 0.43 La 0.457 Sr 0.1 TiO 3 thin film at 50 °C was only 1.263 × 10 −6 S cm −1 but increased to with the postannealing temperature and reached a maximum value of 4.631 × 10 −5 S cm −1 after annealing at 300 °C although it still displayed an amorphous structure from XRD characterization, and the conductivity sharply dropped at a higher annealing temperature of 400 °C (Figure 15b ). [ 158 ]…”

“…The ionic conductivity of the as-deposited Li 0.43 La 0.457 Sr 0.1 TiO 3 thin film at 50 °C was only 1.263 × 10 −6 S cm −1 but increased to with the postannealing temperature and reached a maximum value of 4.631 × 10 −5 S cm −1 after annealing at 300 °C although it still displayed an amorphous structure from XRD characterization, and the conductivity sharply dropped at a higher annealing temperature of 400 °C (Figure 15b). [158] To improve stability and conductivity, B-site substitution has also been widely practiced, including use of trivalent ions Al 3+ , [159] Co 3+ , [159] In 3+ , [159] tetravalent ions Zr 4+ , [160,161] Sn 4+ , [162] and pentavalent ions Ta 4+ , [160,161,162] V 5+ , [163] and Nb 5+ . [163,164] Partial substitution of Ti 4+ by trivalent ions such as Al 3+ causes increased charge carriers, hence resulting in an enhanced ionic conductivity.…”