An investigation of structure and electrical characteristics of lanthanum strontium manganite nanopowders with different Sr²⁺ ion concentrations

Abstract

Generally, the efficiency of solid oxide fuel cells (SOFCs) is heavily dependent on the electrocatalytic activity of the cathode toward the oxygen reduction reaction (ORR). In order to achieve a better cathode performance, LaxSr1-xMnO3 (LSM) nanopowders with different Sr 2+ ion contents varying from 0.2 to 0.8 have been synthesized using the co-precipitation method. The obtained nanoparticles were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and electrochemical impedance spectroscopy (EIS). It is found that the LSM nanoparticles were seemed to exhibit the high polarization resistance with the increase of the Sr 2+ ion molar ratios. The crystallite size was found to increase from 16.4 to 24.3 nm with increasing the Sr 2+ content from 0.2 to 0.8. The lattice parameters were decreased with Sr 2+ ion content which may be caused by an increase in internal stress with increasing the grain size of LSM. Meanwhile, the real part impedance (Z') was increased from 10(Ω) at 0.2 Sr 2+ to be 24(Ω) at 0.8 Sr 2+ ion ratio. Alternatively, |Z| of prepared sample was increased from 12 to 26 (Ω) by increasing Sr 2+ ion molar ratios from 0.2 to 0.8.

Advancements in Perovskite‐Based Cathode Materials for Solid Oxide Fuel Cells: A Comprehensive Review

“…[55] It was shown that increasing Sr concentration up to x = 0.5 in LSM matrix for LSM-YSZ composites is advantageous for both electronic conductivity and polarization resistance. [5,[56][57][58] Nevertheless, normally, compositions ranging from x = 0.15 to x = 0.2 are chosen due to their mechanical suitability with YSZ. [58] Ananyev et al [59] also developed LSM-YSZ composite cathode for SOFC.…”

“…[5,[56][57][58] Nevertheless, normally, compositions ranging from x = 0.15 to x = 0.2 are chosen due to their mechanical suitability with YSZ. [58] Ananyev et al [59] also developed LSM-YSZ composite cathode for SOFC. The oxygen isotope method was adopted to study the exchange kinetics with the oxygen gas phase.…”

Nanofibras De Manganita De Lantânio Dopadas Com Estrôncio: Uma Análise Bibliométrica

“…Existem diferentes métodos de preparação de nanomateriais, os quais utilizam diferentes precursores, e consequentemente resultam em distintos tamanhos e morfologias de nanopartículas, bem como em diferentes propriedades funcionais. Desta forma, as nanopartículas de materiais perovskitas à base LaMnO 3 têm sido frequentemente sintetizadas por métodos tais como: sol gel (Wu et al, 2005), método de citrato (Choi et al, 2018), combustão (Turky et al, 2017), co precipitação (Turky et al, 2018) e síntese hidrotermal (Hehab et al, 2019) É bem conhecido que o controle do tamanho, forma e estrutura dos materiais nanométricos é de fundamental importância para suas aplicações da nanotecnologia. Recentemente, a produção de nanomateriais cerâmicos unidimensionais (nanofibras) tem atraído atenção por diversos pesquisadores, não somente pelos pequenos diâmetros (10-100 nm) das fibras, mas também por sua área superficial elevada, baixa densidade e estrutura porosa (Panda e Sahoo, 2013; Zhi et al, 2012).…”