Metal Cation Pre-Intercalated Ti3C2Tx MXene as Ultra-High Areal Capacitance Electrodes for Aqueous Supercapacitors
Evidence and attribution¶
Authority of statements
Prose sections below (Summary, Methods, Findings, etc.) are curated summaries of the publication identified by doi, title, and pdf_path in the front matter above. They are not new primary claims by this wiki.
For definitive numerical values, reaction schemes, and interpretations, use the peer-reviewed article (and optional records under normalized/papers/ when present)—not this page alone.
Summary¶
Experimental and modeling study of multilayer Ti\(_3\)C\(_2\)T\(_x\) MXene electrodes for aqueous supercapacitors, comparing Na\(^+\), K\(^+\), and Mg\(^{2+}\) pre-intercalation. Electrodes support practical areal loadings (reported up to ~20 mg/cm\(^2\)); K-intercalated material delivers standout rate performance and areal capacitance (up to ~5.7 F/cm\(^2\) in the headline results), with gravimetric values competing with delaminated MXene while greatly improving areal metrics. Ab initio MD (noted in the article text) supports interpretation of intercalant effects alongside electrochemical characterization.
Methods¶
A — Materials synthesis¶
- Multilayer Ti\(_3\)C\(_2\)T\(_x\) with Na\(^+\), K\(^+\), or Mg\(^{2+}\) pre-intercalation (full processing in ACS Appl. Energy Mater. Methods).
B — Electrochemical testing¶
- Aqueous acid electrolyte supercapacitor cells; areal loadings ~5.2–20.1 mg cm⁻²; gravimetric / areal capacitance vs scan rate (abstract highlights ~5.7 F cm⁻² areal for K-intercalated electrodes among reported values).
C — Ab initio molecular dynamics¶
- AIMD with van Duin and Jiang collaborators to interpret ion / interlayer behavior—plane-wave DFT code, functional, timestep (fs), NVT thermostat, and slab/MXene supercell in ACS Appl. Energy Mater. Methods/SI.
D — Other characterization¶
- Microscopy / spectroscopy as enumerated in Methods.
AIMD protocol (DFT-MD, not LAMMPS): 3D PBC supercells; NVT ab initio molecular dynamics at 300 K (or stated temperature in K); ~1 fs or shorter time step per typical BOMD settings in the paper; equilibration and short production ps scale; PBE-class (or stated) DFT exchange correlation; barostat N/A for the NVT AIMD excerpts noted; hydrostatic pressure N/A; external electric field N/A in the static / unbiased AIMD unless the article applies one; replica exchange N/A. Supercell stoichiometry and k-point density in the PDF.
Findings¶
Cation choice strongly modulates capacitance vs scan rate; K\(^+\)-intercalated electrodes show the highest capacitances across rates in the comparisons highlighted. Areal capacitance reaches values well above typical delaminated MXene areal figures and competitive with microengineered electrodes (quantitative benchmarks are stated in the abstract and results).
Additional results (article abstract)¶
- K−Ti 3 C 2 T x exhibited the highest capacitances at different scan rates.
- A gravimetric capacitance comparable to that of delaminated MXene of up to 300 F/g was achieved for multilayer K−Ti 3 C 2 T x but with an outstanding ultra-high areal capacitance of up to 5.7 F/cm 2 , which is 10-fold higher than the 0.5 F/cm 2 of delaminated MXene and exceeds the 4.0 F/cm 2 of microengineered MXene electrodes.
Limitations¶
Long-term cycling, full device integration, and broader electrolyte chemistries are application-dependent; atomistic modeling is used to support mechanism interpretation rather than replace macroscopic device engineering.
Relevance to group¶
Demonstrates collaborative intercalation + AIMD pathway connecting 2D electrode materials to interfacial ion behavior in energy storage contexts involving group participants.
Citations and evidence anchors¶
https://doi.org/10.1021/acsaem.2c00653 — Abstract and Introduction state performance targets; Results/ESI document loadings and electrochemistry tables.