  Advancements in nanotechnology continue to unearth material vistas that
presage a new age of revolutionary functionalities replete with unparalleled
physical properties and avant-garde chemical capabilities that promise sweeping
paradigm shifts in energy, environment, telecommunications and potentially
healthcare. At the upper echelons of this realm, the pnictogen and chalcogen
class of honeycomb layered oxides have emerged with fascinating crystal
chemistry and exotic electromagnetic and topological phenomena that muster
multifaceted concepts spanning from materials science to condensed matter
physics and potential applications in electrochemistry, quantum mechanics and
electronics. In a bid to shed light on the mechanisms governing these
biomimetic nanostructures, this review highlights the significant milestones
and breakthroughs that have augmented their current fundamental theory,
properties, and utilities. Herein, we elucidate the vast promising crystal
chemistry space against the backdrop of known synthesis and characterisation
techniques employed in the development and optimisation of this class of
honeycomb layered oxides. Further, we highlight key theoretical models that
have reinvigorated the exploration and characterisation of within this class of
materials and are poised to redefine the frontiers of material research and
their applications. We conclude by envisaging future research directions where
fascinating physicochemical, topological and electromagnetic properties could
be lurking and where valiant efforts ought to be inclined, particularly in the
prospective realisation of exotic material compositional space as well as their
utility as testing grounds for emergent two-dimensional (2D) topological
quantum gravity and conformal field theories.
