Processing and characterisation of BaZr_0.8Y_0.2O_3−δproton conductor densified at 1200 °C

Abstract

Barium zirconate-based perovskites (BZY) are intensely studied proton conductors for high-temperature electrochemical applications; however, their refractory nature means excessive temperatures are required for sintering (~1700 °C). Although, different strategies have...

Effect of Surface Defect Engineering on Proton Conductivity in Yttrium-Doped Barium Zirconate Thin Films

“…Proton-conducting oxides, which serve as electrolytes, are one of the main components in PCFCs. Among the reported proton-conducting oxides, yttrium-doped barium zirconate (BZY) has been widely investigated because of its high bulk proton conductivity and superior chemical stability. − The protons can be introduced in BZY by the hydration reaction, as shown in the following: normalH 2 normalO + normalV normalO • • + normalO normalO × ⇋ 2 OH normalO • where V O •• , O O × , and OH O • are the oxygen vacancy, lattice oxygen, and hydroxide defect, separately …”

Y doping of BaZrO3 may lead to optimum conditions for proton conduction at operating temperature of solid oxide fuel cells: a first principles study

“…Experimental and theoretical investigations led to the conclusion that Y doped BZO may be a very promising electrolyte [2][3][4][5][6][7][8][9][10][11][12][13]. However, it was found experimentally that the thermodynamic stability of Y doped BZO decreases with increasing Y concentration [14][15][16][17][18][19][20][21]. Moreover, substitution of Y on Ba-or Zr-site may vary the electronic properties by a large extent, because of the ionic radii mismatch and different electron valence state of Y compared to Ba and Zr.…”

“…Moreover, substitution of Y on Ba-or Zr-site may vary the electronic properties by a large extent, because of the ionic radii mismatch and different electron valence state of Y compared to Ba and Zr. By using several experimental techniques, site occupation of Y and the corresponding synthesis conditions were discussed explicitly [15][16][17]. It was found that Y on Ba site increases the Ba deficiency [21,22].…”

Critical role of acceptor dopants in designing highly stable and compatible proton-conducting electrolytes for reversible solid oxide cells

“…[10][11][12][13][14][15] Research focus has gradually shifted from zirconates to cerates due to enhanced conductivity and favorable sinterability. [16][17][18][19][20][21] Undoped barium zirconates or cerates have limited conductivity because proton conduction requires the creation of protonic defects in the ABO 3 perovskite lattice through dissociative adsorption of water (Reaction 1). In order to obtain sufficient proton conductivity under humidified conditions, it is necessary to introduce extrinsic oxygen vacancies by doping to allow for the incorporation of water, and acceptor-doping is the most commonly adopted strategy.…”