NiFe-LDH/MXene nano-array hybrid architecture for exceptional capacitive lithium storage

Abstract

Layered double hydroxides (LDHs) have great advantages in the domain of stored energy because of the exchangeable anions and large specific surface area. Nevertheless, the shortcomings of poor electrical conductivity,...

Cobalt–Nickel Layered Double Hydroxides on Electrospun MXene for Superior Asymmetric Supercapacitor Electrodes

“…The X-ray diffraction (XRD) patterns in Figure S2 reveal a difference between the pre-etched Ti 3 AlC 2 MAX and postetched MXene. 26 A sharp and broad peak at 7° arising from the (002) plane is detected from the etched MXene, indicating a larger interlayer spacing and smaller layer thickness due to selective etching of Al in Ti 3 AlC 2 MAX. 27 The disappearance of the (104) peak at 38.8° from Ti 3 AlC 2 corroborates the etching of Al.…”

“…Ti 3 AlC 2 MAX has a multilayered structure, while the etched MXene has a few-layered structure. The X-ray diffraction (XRD) patterns in Figure S2 reveal a difference between the pre-etched Ti 3 AlC 2 MAX and postetched MXene . A sharp and broad peak at 7° arising from the (002) plane is detected from the etched MXene, indicating a larger interlayer spacing and smaller layer thickness due to selective etching of Al in Ti 3 AlC 2 MAX .…”

In Situ Constructed NiFe-LDH@Ti3C2Tx with a Three-Dimensional Network Structure: Enhanced Li+/Na+ Storage via an Oxygen Bridge

“…The results demonstrated that oxygen bridges could accelerate the electron migration rate of NiFe-LDH@Ti 3 C 2 T x electrodes and enhance their structural stability, and the unique three-dimensional network structure allows rapid exposure of active sites at high current densities. Figure S9 showed the CV curves of NiFe-LDH/Ti 3 C 2 T x and 29 and Shen et al 42 The surface and cross-sectional SEM images of the NiFe-LDH@Ti 3 C 2 T x and NiFe-LDH/Ti 3 C 2 T x before and after 300 cycles at 0.5 A g −1 are illustrated in Figure S11 and The EIS spectra of obtained samples were illustrated in Figure 4f. The EIS spectra consist of a depressed semicircle at high frequency and an inclined line at low frequency, which are related to the charge transfer resistance (R ct ) and Li + diffusion coefficients (D Li+ ), respectively.…”

“…In comparison with the initial cathodic scan, the characteristic peaks of the second cathodic scan shift to 0.72 and 1.51 V, owing to the irreversible electrochemical reaction, relating to the reduction of Ni 2+ and Fe 3+ . 19,29,42,45 In addition, a shift to the right of the cathodic peaks was found in the subsequent cycles, corresponding to a weakening of the electrochemical polarization. NiFe-LDH@Ti 3 C 2 T x also exhibited a characteristic CV curve similar to NiFe-LDH (Figure S7a), suggesting most of the capacity was contributed by NiFe-LDH.…”

Synergistic MXene/LDH heterostructures with extensive interfacing as emerging energy conversion and storage materials

“…146 Similarly, the uniform nanoarrays of NiFe-LDH on Ti 3 C 2 exhibited high electrical conductivity and excellent electrochemical performance with a reversible specific capacity of 894.8 mA h g −1 at 200 mA g −1 when employed as a LIB anode. 155…”