Ti₃C₂T_x MXene-Coupled NiCo-Layered Double Hydroxide Nanosheets with Entire Contact for High-Performance Supercapacitors

Abstract

Layered double hydroxides (LDHs) have been known as attractive alternative electrodes for supercapacitors. However, the restacking of LDHs and poor conductivity still limit their further application. To address these critical issues, in this work, the NiCo-LDH/ Ti 3 C 2 T x nanosheet composites with strong contact have been fabricated by introducing Ti 3 C 2 T x MXenes as the structure-directing substrate. It is found that NiCo-LDH can duplicate the MXene structure to generate sufficient contact, accelerating the electron transfer and exposing abundant electroactive sites to enhance the electrochemical kinetics. The theoretical analysis further confirms that the redox reaction kinetics of the electroactive NiCo-LDH nanosheets can be enhanced by Ti 3 C 2 T x MXenes. Because of these advantages, the as-made NiCo-LDH/Ti 3 C 2 T x electrode shows a good specific capacitance of 1030 F g −1 at 1 A g −1 with a competitive capacitance retention (61% of its initial specific capacitance at 50 A g −1 ). The resultant asymmetric supercapacitor constructed by NiCo-LDH/Ti 3 C 2 T x can achieve a maximum energy density of 59 W h kg −1 at a power density of 0.8 kW kg −1 .

Synergistic coupling of NiVAl-layered double hydroxide with few-layered Ti3C2Tx–MXene nanosheets for superior asymmetric supercapacitor performance

“…6e), indicating that the hybrid supercapacitor device has excellent energy storage potential. 7,28,32,53,60,61 Electrochemical stability is an important indicator for evaluating the performance of supercapacitors. In order to study the cyclic stability of Ti 3 C 2 T x -MXene/NiVAl-LDH//AC devices, GCD tests were conducted at 10 A g À1 (Fig.…”

“…The prepared Ti 3 C 2 T x -MXene should be stored at 4 1C. 1,9,32,33 2.3 Preparation of Ti 3 C 2 T x -MXene/NiVAl-LDH Add NiSO 4 Á6H 2 O (0.9 mmol), AlCl 3 Á6H 2 O (0.3 mmol), VCl 3 (0.3 mmol), 0.5 g of urea and 0.05 g of C 6 H 8 O 7 ÁH 2 O to 30 mL of deionized water. Add an appropriate amount of Ti 3 C 2 T x -MXene to the above solution and stir it thoroughly to mix evenly.…”

Transport channel engineering between MXene interlayers for Zn‐ion hybrid microsupercapacitor with enhanced energy output and cycle stability

“…[35][36][37] This strategy can greatly facilitate ion transfer kinetics and further enable self-assembled MXene film electrodes with enhanced charge storage capacity. [38][39][40][41][42][43] However, it is at the expense of electron transfer kinetics within MXene film electrodes. Therefore, it is critical to regulate interlayer ion transfer and electron transport within MXene capacitor-type electrodes precisely to realize higher areal energy density for MXene-based ZHMSCs (Scheme 1).…”

In-situ fabrication of Cr doped FeNi LDH on commercial stainless steel for oxygen evolution reaction

“…Thus, it is necessary to design and synthesize highly efficient, stable and non-precious electrocatalysts.Many studies have been devoted to develop low cost and highly active electrocatalysts for OER based on the transition mental based compound (TMs) 7-10 . Among them, metal layered double hydroxides (LDHs) and oxyhydroxides have been widely reported due to their special two-dimensional structure, ion intercalation ability and considerable catalytic activity for OER [11][12][13][14][15][16] . Compared to other bimetallic LDHs, FeNi based LDHs is considered as promising OER electrocatalysts because of their low kinetic barriers in the rate-determining step as effective OER electrocatalysts in alkaline solutions [17][18][19][20][21] .…”