Enhanced Ionic Transport and Compressive Residual Stress in Er-Doped Bi2O3 with Lower Er3+ Concentrations

• Published in: Journal of electronic materials 2018-09, Vol.47 (9), p.5422-5432
• Main Authors: Concha-Balderrama, A., Martinez-Rodriguez, H. A., Rojas-George, G., Esparza-Ponce, H. E., Orozco-Carmona, V., Pizá-Ruiz, P., Bocanegra-Bernal, M. H., Reyes-Rojas, A.
• Format: Article
• Language: English
• Subjects: Bismuth oxides; Bismuth trioxide; Cations; Characterization and Evaluation of Materials; Chemistry and Materials Science; Compressive properties; Conductors; Crystallography; Electronics and Microelectronics; Erbium; Fluorite; Grain boundaries; Instrumentation; Ion currents; Materials Science; Nanoparticles; Optical and Electronic Materials; Residual stress; Sol-gel processes; Solid State Physics
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-018-6441-0

Er 3+ -doped (Bi 1− x Er x ) 2 O 3 (where x  = 0.1, 0.13, 0.15, and 0.2) nanoparticles (NPs) with a single fluorite-type structure have been synthesized by the sol–gel method and sintered at 850°C for 3 h. Here E 2 O 3 -stabilized δ -Bi 2 O 3 has been obtained at low erbium concentrations. Rietveld refinement confirms an Ln-O bond length increase by a crystallographic volume variation from 166.51(1) to 168.54(1) Å 3 , as a consequence of enhanced ionic conductivity, which proved to be inversely proportional to the increase in Er 3+ concentration. A reduction in the small cation (Er 3+ ) concentration ( x  = 0.1) induces a grain boundary resistance decrease in the intermediate temperature (IT) range. A marked compressive stress tensor at high temperature was also observed, even at lower Er 3+ cation concentrations, where the tetragonal structure takes place. The β -(Bi 1− x Er x ) 2 O 3 solid-state oxide ion conductor proved to have potential as a solid oxide electrolyte at ITs due to its conductivity and high compressive residuals stress (− 370 MPa).