tracking, and recording people’s vital signs have seen advancements due to wearable and

implantable devices or electronics [3]. The factors at the interfaces between biosensors

and cellular membranes determine the efficacy of these kinds of devices. The electro­

physiology recording and stimulating capabilities of biosensor implants integrated with

electrogenic cells, on the other hand, are reliant on the electrode impedance, the revealed

surfaces area, and the cell-electrode connectivity [4–7]. Smart watches, armbands, and

optics are among the accessories that are bringing some of these technologies into our

day-to-day lives [1,8,9]. The commercialization of these gadgets has been aided by

semiconductor nanostructured bio-nanotechnology. The flexibility of nanomaterials in

terms of alteration and modification of their localized structure during the synthesis, as

well as their doping and functionalization capabilities, allows them to serve the specific

requirements of such applications. This unique nature of the nanomaterials has

made them multi-functional prerequisites for the conception of flexible and wearable

electronics [10]. The downsizing of semiconductor devices is paving the way for new

biomedical research and commercial medical applications. A basic way for manu­

facturing very flexible electronics is to utilize inorganic materials in form of either one-

dimensional (1D) or two-dimensional (2D) nanostructures [11]. Many inorganic materials,

namely nanosheet, nanoribbon, and nanowire, provided tunable and dynamic features

for conductor and semiconductor devices as well as dielectric materials [11].

Carbon nanotubes (CNTs), followed by several 2D materials, were among the first nano­

materials to be investigated for the designing of wearable electronics [12]. With the best active

electrical conductivities and higher electron mobility, flexibility in single layer form, the

optical transparency of 98.7%, and extraordinarily high tensile strength, graphene materials

have emerged as the most promising and extensively researched 2D materials. The graphene

also demonstrates exceptional resistance to high temperatures, pressures, and highly

corrosive conditions. Graphene is a suitable candidate for wearable biosensors and other

biomedical applications because of its ease of fabrication and bio-compatibility [13,14].

Electronic and optical bio-interface studies mainly use inorganic semiconductors. They are

needed to make high-performance devices for applications like electrical sensing, signal

amplification, and transduction. Researchers have increasingly focused on semiconducting

Si because of its biocompatibility and well-developed micro-fabrication technologies. Other

inorganic semiconductors explored in bioelectronics and bioelectrical research include zinc

sulfide (ZnS), titanium dioxide (TiO2), and molybdenum disulfide (MoS2), which are

available as nanoparticles, nanowires, nanotubes, layered nanomaterial, and nanosheets [2].

Semiconducting oxides, in particular, are growing rapidly as silicon substitutes in active

matrix display backplane thin-film transistors, as well as opaque, elastic devices and energy

scavengers [15]. ZnO has a unique combination of properties such as excellent visible wa­

velength transparency, rapid charge carrier mobility, and high piezoelectric susceptibility.

Therefore, it has been explored in a variety of forms, including films, wires, and rods, for

sensing, catalysis, optical emission, piezoelectric transduction, and actuation. ZnO is also

potentially ideal for chemical sensing, biological labeling and sensing, and energy transfer at

bio-interfaces due to its stability, various band gaps, and wide range of morphologies [15,16].

Transition metal dichalcogenide (MoS2) could be used in ultrathin wearable touch sensors,

owing to their outstanding photo-absorption and piezoresistivity [17].

The first functional implants, heart pacemakers, were introduced in the 1950s [18]. Since

then, the emergence of implantable electronic devices has streamlined the evolution of

nanoelectronics and nanofabrication technologies. Biomedical devices that help restore

and manage the activities of dysfunctional parts include hearing aid, nervous system

stimulators, and cardiac pacemakers [19]. These battery-operated implantable devices are

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