15.1 Introduction
The word “bioelectronics” refers to the fusion of biology with electronics and refers to a
wide range of bio-related structures utilized within the electrochemical community in
broader applications [1]. The term “bioelectronic interface” refers to a variety of bio-
integrated electrodes that communicate with biological systems. Bioelectronic interfaces
are created on the surface of the human skin, or within the human body. The interfaces
can be designed for electro-stimulation [2], as target applications and physiological signal
recording [3]. Despite the different modalities and form factors of extant bioelectrodes,
some common principles govern the configuration and manufacture of bioelectronic in
terfaces having high-performance, like minimum interfacial impedance. The fundamental
differences between organic tissues and artificial electronics, on the other hand, cannot be
overlooked. Human skin is permeable at epidermal interfaces, but electronics normally
require tight encapsulation for long life spans. Tissues are ironically conductive, soft, and
implanted interfaces, yet traditional electronics are hard, water-exclusive, and electro
nically conductive. As a result, connecting stiff electrodes with curved, complex, and
dynamic tissues of the human body poses substantial obstacles. This field has made
significant developments recently, although the extent of that advancement is dependent
on material innovation. The appearance of two-dimensional (2D) structured materials
has spurred the bioelectronics area of research over the last decade. Following gra
phene’s breakthrough are black phosphorous, transition metal dichalcogenides, gra
phitic C3N4, and metal−organic frameworks [1]. MXenes have been applied in different
areas, including bioelectronic and biomedical applications, thanks to the attempts made
by chemists and materialists. Apart from their two-dimensional layered structure, these
new two-dimensional materials have unique physicochemical and electronic proper
ties, large surface areas, two-dimensional tunable architectures, DNA, cells, and they
effectively interact covalently with small biomolecules, proteins, and many other small
molecules and other biocreatures are just a few of the advantages. As a result of these
unique features, 2D materials have a lot of potential in a variety of applications, in
cluding drug delivery vehicles, biosensors, bioimaging agents, bioelectronics, and
cancer therapy platforms [4].
The recent development of a 2D-layered chemical family known as “MXenes” has pi
qued the scientific community’s interest, owing to special electronic and structural
properties, which allow them to be used in a variety of applications. MXenes are the name
given to a category of transition metal carbides, nitrides, and carbonatites that are pro
duced by chemical delamination of MAX phases, which are 3D ternary (or quaternary)
compounds.
Ti3C2Tx (short Ti3C2) is the most researched MXene to date, with Tx denoting surface
terminations, which are commonly O, OH, and/or F. A novel form of MAX phase, known
as i-MAX, was recently identified, resulting in an MXene with in-plane vacancy ordering.
The first vacancy MXene, in addition to having a high conductivity, has shown a sig
nificant capacity to construct supercapacitors [5]. The use of spontaneous transfers of
electrons among MXenes and organic monomers to facilitate the polymerization of the
organic monomers to form composite films has proven to be very successful in recent
years. These approaches, on the other hand, take a long time and do not produce an
ordered composite film in a single step, which must later be achieved through vacuum
filtration. MXene, which is normally negatively charged, is extremely similar to electro
lyte ions in a colloidal solution [6]. When MXene is added to the electropolymerization
238
Bioelectronics