Nickel MXene Nanosheet and Heteroatom Self-Doped Porous Carbon-Based Asymmetric Supercapacitors with Ultrahigh Energy Density

Abstract

For high-energy-density supercapacitors, two-dimensional (2D) MXenes are being increasingly explored due to their inherent conductivity and excellent chemical properties. However, MXenes failed to achieve high power density and exceptional stability. Addressing this, we report the fabrication of an asymmetric supercapacitor with nickel MXene (cathode) and nitrogen (N), sulfur (S), and phosphorus (P) self-doped biomassderived activated carbon (anode). Detailed structural and chemical characterization studies reveal layered nanosheets in NiMX caused due to solvothermal etching cum exfoliation and unique micro− mesopore distribution in the optimized Euphorbia milii plant leafderived heteroatom self-doped activated carbon (EMAC-700) because of KOH activation. NiMX and EMAC-700 delivered high capacitances of 474.3 and 575.8 F/g, respectively, at 1 A/g with a 6 M KOH electrolyte. This is attributed to the pseudonature of NiMX and the presence of heteroatoms and the large surface area (2349 m 2 /g) of EMAC-700, facilitating fast electrolytic ion transfer. Finally, an asymmetric device with NiMX//EMAC configuration in 6 M KOH delivered a 152.6 F/g cell capacitance at 0.5 A/g under 0−1.5 V. Additionally, an ultrahigh energy density of 47.6 W h/kg at a 375 W/kg power density was achieved along with an 81.7% capacitance retention after 30,000 cycles at 15 A/g, signifying its potential for next-generation energy storage applications.

2D V2C MXene Based Flexible Gas Sensor for Highly Selective and Sensitive Toluene Detection at Room Temperature

“…Moreover, V 2 C possesses a thin atomic layer which stimulates the adsorption and desorption of analytes on the sensing materials. 34,35 To the authors' knowledge, this is the first report on the V 2 C MXene based flexible RT toluene gas sensor. The polyester film based transparent sheet was used to fabricate the flexible sensor.…”

“…V 2 C is one of the nanomaterials in the MXenes family that comprises two M layers and one C layer, whereas Ti 3 C 2 accommodates three Ti layers and two C layers. Moreover, V 2 C possesses a thin atomic layer which stimulates the adsorption and desorption of analytes on the sensing materials. , …”

Recent advances in Ni-materials/carbon nanocomposites for supercapacitor electrodes

“…Table 3 166–181 demonstrates that supercapacitor electrodes based on a combination of Ni materials and porous carbon materials are widely used to enhance energy storage applications. Porous carbon, such as activated carbon or carbon nanotubes, provides a large surface area for electrochemical reactions and ion adsorption.…”

“…Due to the ultrathin thickness of LDHs, large specific surface area, low charge transfer resistance, and high wettability with electrolyte, the Ni 2 Co1-LDHs/BC50 electrode revealed an ultra-high S.C. and the Ni 2 Co1-LDHs/BC50//YP-80F HSC delivered a maximum specific energy of 52.47 W h kg −1 . 179 Nanda et al 180 synthesized Ni MXene (cathode) and Euphorbia milii plant leaf-originated and N, S, P self-doped AC (EMAC-700) (anode). NiMX and EMAC-700 delivered high capacitances of 474.3 and 575.8 F g −1 , respectively, attributed to the pseudo nature of NiMX, the presence of heteroatoms, and the large surface area of EMAC-700.…”

Fabrication of high-performance triboelectric nanogenerator based on Ni3C nanosheets to self-power thermal patch for pain relief

“…This process is demonstrated in figure 1(a). was synthesised by a high-temperature synthesis technique as per the previously reported work by other members of group [15]. Using a mortar and pestle, stoichiometric amounts of NiO, Al, and C 3 H 6 N 6 were combined and pounded to a fine powder.…”