Effect of Oxygen Content on the Properties of the HoBaCo2O5+x Layered Cobaltite

TL;DR

This study systematically investigates how oxygen content influences the structural, thermal, and magnetic properties of HoBaCo2O5+x layered cobaltite, revealing that even minor variations significantly affect its behavior.

Contribution

It provides the first detailed experimental analysis of oxygen content effects on HoBaCo2O5+x properties, including measurement techniques and sample quality verification strategies.

Findings

Oxygen content variation dramatically affects magnetic and transport properties.

Precise control of oxygen levels is crucial for material performance.

Sample quality can be verified through annealing procedures.

Abstract

In this work we present the result of the first experimental investigation of the role of oxygen content on the properties of the HoBaCo2O5+delta layered cobaltite. We have measured the variation of oxygen content as a function of temperature and oxygen partial pressure by means of thermogravimetry coupled to chemical titration analysis. On selected samples of accurately known oxygen content we have undertaken a systematic investigation of their structural, thermal and magnetic properties by means of x-ray diffraction, differential scanning calorimetry and magnetometry. The overall results gained by this study confirm the central role of oxygen content on the properties of these materials suggesting that, for the Ho composition, even very slight variation of the order of delta=0.01 has a dramatic influence on the magnetic and transport properties of the samples. In addition, we have presented results showing the strategy to check the quality of samples prepared at selected oxygen contents by annealing procedures.