The minimum room-temperature resistivity for La–Mn–codoped BaTiO3 occurred at [La+3]-5/3[Mn+ x ]∼0.35 mol%. Most of the Mn acceptors were in the bulk regions, existing as Mn+2 ions. The others, existing as Mn+3 ions, cause the grain growth inhibition effect and should exist at the grain boundaries, similar to an acceptor level. The slope of the positive temperature coefficient resistance (PTCR) effect (ρ160° C/ρ120° C) was increased with increasing Mn content. However, the maximum order of PTCR (ρ max/ρ min) existed at [Mn+ x ]∼0.06 mol%.
No takes yet. Share an insight, caveat, or question.
Chen et al. (1994) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: