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Titanium carbide/reduced graphene oxide (Ti 3 C 2 T z /rGO) gels were prepared by a one-step hydrothermal process. The gels show a highly porous structure with a surface area of ∼224 m 2 g −1 and average pore diameter of ∼3.6 nm. The content of GO and Ti 3 C 2 T z nanosheets in the reaction precursor was varied to yield different microstructures. The supercapacitor performance of Ti 3 C 2 T z /rGO gels varied significantly with composition. Specific capacitance initially increased with increasing Ti 3 C 2 T z content, but at high Ti 3 C 2 T z content gels cannot be formed. Also, the retention of capacitance decreased with increasing Ti 3 C 2 T z content. Ti 3 C 2 T z /rGO gel electrodes exhibit enhanced supercapacitor properties with high potential window (1.5 V) and large specific capacitance (920 F g −1 ) in comparison to pure rGO and Ti 3 C 2 T z . The synergistic effect of EDLC from rGO and redox capacitance from Ti 3 C 2 T z was the reason for the enhanced supercapacitor performance. A symmetric two-electrode supercapacitor cell was constructed with Ti 3 C 2 T z /rGO, which showed very high areal capacitance (158 mF cm −2 ), large energy density (∼31.5 μW h cm −2 corresponding to a power density of ∼370 μW cm −2 ), and long stability (∼93% retention) after 10 000 cycles.
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Synergetic Effect of In Situ Formed TiO 2 in MXene for Enhanced Energy Storage in High-Performance Supercapacitors
This study explores and presents a comprehensive understanding of the synergistic effect of in situ formed TiO2 in Ti2C MXene (TTMXene) nanomaterials to derive enhanced energy characteristics in high-performance flexible symmetric supercapacitors. The TTMXene two-dimensional (2D) (nanocomposite) materials were synthesized by a simple single-step chemical etching method. The TTMXene thus formed exhibits a layered structure with an average particle size in the range of 10−50 nm. The electrochemical studies demonstrate that the TTMXene nanocomposite exhibits a specific capacitance of 729 F g−1 at a current density of 0.5 A g−1 . This enhanced performance is due to utilizationofa highactivesurfaceareaand excellentelectronicconductivityofthe in-situ formed TiO2 in Ti2C MXene. The prototype of a flexible symmetric TTMXene supercapacitor was fabricated and characterized. The TTMXene// TTMXenedemonstratedanexcellentenergydensityof152.3Whkg−1 atapower density of 0.215 kW kg−1 and retained 88% specific capacitance after 10,000 cycles. These findings highlight that the TTMXene nanocomposites are exceptional candidates for future flexible supercapacitor devices with long-term and superior performance.
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- Award ID(s):
- 1827745
- PAR ID:
- 10632506
- Publisher / Repository:
- ACS
- Date Published:
- Journal Name:
- ACS Applied Energy Materials
- Volume:
- 8
- Issue:
- 2
- ISSN:
- 2574-0962
- Page Range / eLocation ID:
- 1308 to 1321
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1021/acsaem.4c02769
