Experimental and Computational Analysis of MnO2@V2C-MXene for Enhanced Energy Storage

Abstract

Herein, we studied the novel and emerging group of 2D materials namely MXene along with its nanocomposites. This work entails detailed experimental as well as computational study of the electrochemical behavior of vanadium carbide (V2CTx) MXene and MnO2-V2C nanocomposite with varying percentages of MnO2. A specific capacitance of 551.8 F/g was achieved for MnO2-V2C nanocomposite in 1 M KOH electrolyte solution, which is more than two times higher than the gravimetric capacitance of 196.5 F/g obtained for V2C. The cyclic stability achieved for the MnO2-V2C nanocomposite resulted in a retentivity of 96.5% until 5000 cycles. The c-lattice parameter achieved for MXene is 22.6 Å, which was 13.01 Å for MAX phase. The nanocomposite resulted in a c-lattice parameter of 27.2 Å, which showed that the spatial distance between the MXene layers was efficiently obtained. The method of wet etching was used for the preparation of pristine MXene and the liquid phase precipitation method was opted for the synthesis of the MnO2-V2C nanocomposite. Density functional theory calculation was exercised so as to complement the experimental results and to understand the microscopic details, such as structure stability and electronic structure. The current report presents a comprehensive experimental and computational study on 2D MXenes for future energy storage applications.

Ag Nanoparticle-Decorated V2CTx MXene Nanosheets as Catalysts for Water Splitting

“…This is due to the existence of a trace of MAX phase yet after the etching process. 40 The obtained Raman spectra agreed well with previously published Raman studies. Peaks at 281 cm −1 (E g ) and 406 cm −1 (A 1g ) are associated with V atoms vibrating in-plane and out of the plane, respectively.…”

“…In addition to the V–C peaks, vibrational peaks of Al–V have been found in the hybrid sample. This is due to the existence of a trace of MAX phase yet after the etching process …”

Nickel-adsorbed two-dimensional Nb2C MXene for enhanced energy storage applications

“…2(a) ) similar to exfoliated graphite exhibiting distinct sheet splitting. 32 Similarly, Ni–Nb 2 CT x showed layered morphology with fine slanted nano-sheets ( Fig. 2(b) ).…”

“…In addition to this, the doping metals in MXene also include Gd, 29 Co, 25 Cr, 30 Fe 3 O 4 , 31 MnO 2 . 32 In comparison with other, Ni possessed high electrochemical behavior because of their better electronic conductivity and rich redox reactions and has been explored widely in different materials. 33 Moreover, the size of the ionic radii of niobium Nb 2+ (0.08 nm) is almost comparable to the ionic radii of nickel Ni 2+ (0.07 nm); thus, making nickel an appropriate candidate to be doped in Nb 2 C MXene.…”

MWCNT-modified MXene as cost-effective efficient bifunctional catalyst for overall water splitting

“…38 MXenes have been widely explored for their use in lithium-ion-battery (LIBS) 39 and supercapacitors. [40][41][42] Due to the active surface functionality and chemical inertness in electrochemical potential, MXene is predicted to be a heterogeneous catalyst. 43,44 However, very limited literature is available for the catalytic behavior of MXene.…”