Pseudocapacitive Electrodes Produced by Oxidant‐Free Polymerization of Pyrrole between the Layers of 2D Titanium Carbide (MXene)

Abstract

Heterocyclic pyrrole molecules are in situ aligned and polymerized in the -absence of an oxidant between layers of the 2D Ti3C2Tx (MXene), resulting in high volumetric and gravimetric capacitances with capacitance retention of 92% after 25,000 cycles at a 100 mV s(-1) scan rate.

Schottky-Barrier-Free Contacts with Two-Dimensional Semiconductors by Surface-Engineered MXenes

“…This process leads to T = O, OH, and/or F. The layers are then exfoliated by sonication 1,2,5 . MXenes have already shown a great potential in batteries [6][7][8][9] , capacitors 5,10,11 , and water treatment 12,13 .…”

MXene‐Based Composites: Synthesis and Applications in Rechargeable Batteries and Supercapacitors

“…In-situ polymerization can be achieved by mild physical agitation, [73] electrodeposition [202] or UV radiation. [203] In the in situ polymerization process, the highest occupied molecular orbitals (HOMOs) and the lowest unoccupied molecular orbitals (LUMOs) of the substrate (MXene) and monomer are shown in Figure 7f, as well as the two main types of electron transfer.…”

“…It is beyond doubt that in the blending process, the monomer needs to be as adjacent as possible to MXene for electron transfer to complete the polymerization. [73] In the UV radiation-induced polymerization process (Figure 7e), a mixed sample of MXene power and monomer is stirred under UV light to polymerize the monomer on the surface of MXene. Chen et al calculated that the polymer monomer is most likely attached to the MXene surface in parallel.…”

“…[155] The in situ growth of CTAB-grafted SCNTs on Ti 3 C 2 T x surfaces greatly increases its capacitance and shows superior performance than the ones of ex situ derived Ti 3 C 2 T x /SCNT composites (Figure 10a,b). [73,202] Common MXene-based composites for SCs are shown in Table 4. From Figure 10c,d, an easily bulk-expanded MnO 2 is uniformly dispersed on the surface of Ti 3 C 2 T x .…”

“…[48] M 3 X 2 T x ratios MXenes have revealed drawbacks such as restacking, easy oxidation, and low electrical conductivity, inhibiting the development of pure M 3 X 2 T x . So far, the MXene-based composites have been successfully synthesized with metals, [59][60][61][62] metal sulfides, [63] metal oxides, [60,64,65] mesoporous carbon, [66,67] graphene, [68] high-quality graphene, [69] carbon nanotubes, [70] carbon fibers, [71,72] polypyrrole, [73] etc., and its applications have been exploited in various fields, for instance, batteries, [74] supercapacitors (SCs), [75] electromagnetic wave absorption, [59,76] water purification, [77] etc. So far, the MXene-based composites have been successfully synthesized with metals, [59][60][61][62] metal sulfides, [63] metal oxides, [60,64,65] mesoporous carbon, [66,67] graphene, [68] high-quality graphene, [69] carbon nanotubes, [70] carbon fibers, [71,72] polypyrrole, [73] etc., and its applications have been exploited in various fields, for instance, batteries, [74] supercapacitors (SCs), [75] electromagnetic wave absorption, [59,…”