Diacid Molecules Welding Achieved Self-Adaption Layered Structure Ti₃C₂MXene toward Fast and Stable Lithium-Ion Storage

Abstract

Ti 3 C 2 has been considered as a potential material for lithium-ion storage because of its abundant surface terminals, excellent metal-like conductivity, and modifiable layered structure. However, the Li + diffusion rate in interlayer is limited by the small interlayer spacing determined by the van der Waals forces. Herein, the dehydration condensation reaction between amino-functionalized Ti 3 C 2 (Ti 3 C 2 -NH 2 ) and maleic acid (MA) molecules was utilized to enlarge the interlayer spacing of Ti 3 C 2 . The MA molecules were successfully welded into interlayers of Ti 3 C 2 by HN−CO bonds (namely, chemical welding) and MA chemical welded Ti 3 C 2 (MA-Ti 3 C 2 ) with self-adaption layered structure were obtained. The MA molecules can contribute double effects to the layered structure of Ti 3 C 2 , and they act as chains to remit the volume change during Li + insertion and serve as pillars to enhance the structure stability during Li + extraction. The MA-Ti 3 C 2 exhibits an interlayer spacing of 1.28 nm, a fast Li + diffusion rate (1.4 × 10 −8 to 5.8 × 10 −7 cm 2 s −1 ), and improved Li + storage performance. The MA-Ti 3 C 2 //AC lithium-ion capacitor (LIC) demonstrates an excellent energy density of 102.5 Wh kg −1 at 200 W kg −1 and cycle stability with 76.3% at 1.0 A g −1 after 1000 cycles. This novel chemical welding delivers an effective perspective for modifying the layered structure, enhancing the structure stability, and achieving fast Li + diffusion and high-rate capability of twodimension materials.

Exploring 2D Energy Storage Materials: Advances in Structure, Synthesis, Optimization Strategies, and Applications for Monovalent and Multivalent Metal‐Ion Hybrid Capacitors

“…Organic molecules (such as maleic acid, [177] sodium tricyanomelaminate, [178] diamine [179] and p-phenylenediamine (PPDA) [180] )-intercalated 2D materials were also reported with significantly improved performance. Zhang et al proposed a facile chemical welding method to construct diamine molecules (xDM, x = 2, 3, 4, 6, and 8) pillared-and strained-graphene oxides (GO) with controllable interlayer space via the dehydration condensation reaction between GO and xDM (Figure 11d).…”

Low-Triggering-Potential Electrochemiluminescence from a Luminol Analogue Functionalized Semiconducting Polymer Dots for Imaging Detection of Blood Glucose

“…Moreover, ATR-FTIR and XPS measurements were used to confirm that ABEI molecules were covalently coupled to the surface of Pdots. As presented in Figure C, compared with Pdots, ABEI-Pdots exhibited two new peaks at 3365 and 1645 cm –1 , which are the NH and CO (amide 1 band) stretching vibrations of the primary amide, respectively. − These two peaks prove the existence of an amide bond generated by the coupling of ABEI and Pdots. Such structure changes were further verified by a XPS spectra.…”

“…Compared with the C 1s spectrum of Pdots, the binding energy of CO of ABEI-Pdots dropped about 1 eV from 288.8 to 287.9 eV, which was due to the formation of amide bonds in the ABEI-Pdots. 55,56,58 In addition, the proportion of CO double bonds slightly raised from 2.88% to 3.44%, originating from ABEI molecules (Table S1). More obviously, the deconvolution of the N 1s spectrum from the ABEI-Pdots showed three curvedfitted components peak at 399.3, 400.7, and 402.9 eV (Figure 1F), which were contributed to the -N−sp 3 C, -N−sp 2 C, and N− O, respectively.…”

Sacrificial Template Synthesis of Two-Dimensional Few-Layer MoSe2 Coupled with Nitrogen-Doped Carbon Sheets for High-Performance Sodium Ion Hybrid Capacitors

“…From the above kinetics and EIS data, it can be inferred that the introduction of unique 2D nitrogen-doped carbon sheets can effectually facilitate the Na + transfer kinetics. 59,60 Figure S13a depicts the galvanostatic intermittent titration technique (GITT) curves to evaluate the diffusion coefficient of Na + (D Na+ ) in the MoSe 2 @NCS. The D Na+ value can be calculated by the follow eq 6: 61…”

“…As displayed in Figure S12, the MoSe 2 @NCS shows a smaller semicircle than bulk MoSe 2 , demonstrating higher electronic conductivity and lower charge-transfer resistance of MoSe 2 @NCS. From the above kinetics and EIS data, it can be inferred that the introduction of unique 2D nitrogen-doped carbon sheets can effectually facilitate the Na + transfer kinetics. , Figure S13a depicts the galvanostatic intermittent titration technique (GITT) curves to evaluate the diffusion coefficient of Na + ( D Na+ ) in the MoSe 2 @NCS. The D Na+ value can be calculated by the follow eq : where τ is the time of the pulse current, m B , V M , and M B are the mass, molar volume, and molar mass of active material, respectively, A is the surface area of the electrode, Δ E s and Δ E τ are the respective steady-state potential difference before and after the application of current pulse and change of voltage during the constant current pulse.…”