Increasing the stability range of substituted delta-Bi2O3 oxide ion conductors: a high entropy dopant approach.

It has been demonstrated that “stabilised” bismuth oxides can be successfully incorporated into intermediate temperature solid oxide fuel cells. These “stabilised” bismuth oxides generally have lower conductivity than bismuth oxide itself, due to dopant-vacancy interactions, with conductivity significantly decreasing with increasing dopant level. Here we use a high entropy dopant (HED) approach to stabilise the highly conducting -Bi2O3 phase at much lower dopant levels than can be achieved using a single dopant allowing for significantly higher conductivities to be attained. This proposal seeks to clarify the oxide ion vacancy/interstitial distribution in three new HED stabilised bismuth oxides, with a view to correlating these structural changes with changes seen in the conductivity behaviour as a function of temperature.

已有研究证实，经稳定化处理的氧化铋（stabilised bismuth oxides）可成功整合至中温固体氧化物燃料电池（intermediate temperature solid oxide fuel cells）当中。此类稳定化氧化铋的电导率通常低于纯氧化铋，这源于掺杂剂-空位相互作用，且电导率会随掺杂剂浓度升高而显著降低。本研究采用高熵掺杂剂（high entropy dopant, HED）策略，能够在远低于单一组分掺杂所需的掺杂水平下，稳定高导电的δ-Bi₂O₃晶型，从而实现更高的电导率。本研究计划阐明三种新型高熵掺杂剂稳定化氧化铋中的氧离子空位/间隙分布，以期将这些结构变化与电导率随温度变化的行为建立关联。