Phase transition in oxygen-intercalated pseudocapacitor Pr$_2$MgZrO$_6$ electrode: A combined structural and conductivity analysis

TL;DR

This study investigates the phase transition, structural changes, and charge storage mechanisms of Pr$_2$MgZrO$_6$ as an oxygen-intercalated pseudocapacitor electrode, revealing a phase transition, conductivity change, and pseudocapacitive behavior with high capacitance.

Contribution

The paper provides a comprehensive analysis of the structural phase transition and electrochemical properties of Pr$_2$MgZrO$_6$, highlighting its potential as a pseudocapacitor electrode with detailed mechanistic insights.

Findings

Identified a monoclinic to tetragonal phase transition in PMM.

Observed semiconductor to metal transition in ac conductivity.

Achieved a maximum specific capacitance of 257.57 F for the electrode.

Abstract

The phase transition behavior and charge storage mechanism of Pr$_2$MgZrO$_6$ (PMM), an oxygen-intercalated pseudocapacitor, were investigated through crystal structure analysis, Raman spectroscopy, ac conductivity spectroscopy, X ray photoelectron spectroscopy, and electrochemical spectroscopy. The crystal structure analysis and vibration studies revealed a phase transition in PMM, following the sequence 14 to 87 to 225. High temperature Raman spectroscopy demonstrated a significant feature of a monoclinic to tetragonal phase transformation in PMM. The ac conductivity spectroscopy exhibited a semiconductor to metal transition in PMM. X-ray photoelectron spectroscopy of the Mn 2p state confirmed the presence of oxygen vacancies in PMM at room temperature. Furthermore, the electrochemical performance of PMM as an electrode was evaluated. The PMM electrode displayed an intercalated pseudocapacitive nature, exhibiting a maximum possible specific capacitance of 257.57 F. The charge storage process of the PMM electrode was thoroughly reviewed and discussed, shedding light on the underlying mechanisms.