Tuning MXene Properties through Cu Intercalation: Coupled Guest/Host Redox and Pseudocapacitance
OPEN ACCESS
Loading...
Author / Producer
Date
2024-04-09
Publication Type
Journal Article
ETH Bibliography
yes
Citations
Altmetric
OPEN ACCESS
Data
Rights / License
Abstract
MXenes are 2D transition metal carbides, nitrides, and/or carbonitrides that can be intercalated with cations through chemical or electrochemical pathways. While the insertion of alkali and alkaline earth cations into Ti3C2Tx MXenes is well studied, understanding of the intercalation of redox-active transition metal ions into MXenes and its impact on their electronic and electrochemical properties is lacking. In this work, we investigate the intercalation of Cu ions into Ti3C2Tx MXene and its effect on its electronic and electrochemical properties. Using X-ray absorption spectroscopy (XAS) and ab initio molecular dynamics (AIMD), we observe an unusual phenomenon whereby Cu2+ ions undergo partial reduction upon intercalation from the solution into the MXene. Furthermore, using in situ XAS, we reveal changes in the oxidation states of intercalated Cu ions and Ti atoms during charging. We show that the pseudocapacitive response of Cu-MXene originates from the redox of both the Cu intercalant and Ti3C2Tx host. Despite highly reducing potentials, Cu ions inside the MXene show an excellent stability against full reduction upon charging. Our findings demonstrate how electronic coupling between Cu ions and Ti3C2Tx modifies electrochemical and electronic properties of the latter, providing the framework for the rational design and utilization of transition metal intercalants for tuning the properties of MXenes for various electrochemical systems.
Permanent link
Publication status
published
External links
Editor
Book title
Journal / series
Volume
18 (14)
Pages / Article No.
10124 - 10132
Publisher
American Chemical Society
Event
Edition / version
Methods
Software
Geographic location
Date collected
Date created
Subject
2D materials; in situ X-rayabsorptionspectroscopy; ab initio molecular dynamics; MXenes; pseudocapacitance; transition metalintercalation; charge storage mechanism
Organisational unit
09692 - Lukatskaya, Maria / Lukatskaya, Maria