  The integration of functional molecules onto conductive or dielectric
surfaces represents a promising avenue for employing molecule-centric
technologies, encompassing sensor development, electrochromic, and the
facilitation of charge and spin transport at the nanoscale These assemblies
exhibit robust physical and chemical stability, exerting influence not only on
the interfacial properties of pertinent surfaces but also on the
characteristics of the assembled molecules themselves. Within the spectrum of
available molecules, metal-polypyridyl complexes have emerged as focal points
of investigation for generating surface-bound assemblies, encompassing
monolayers or multilayers, achieved through pre- or post-functionalization
methodologies. The appeal of these complexes lies in their inherent
versatility, stemming from facile synthesis, appreciable stability, and tunable
properties encompassing redox behaviors, reactivity in excited states,
luminescent emissions, excited state longevity, as well as responsiveness to
stimuli-induced electron and energy transfer. This comprehensive review aims to
delve into the nuanced traits and applications of surface-bound
metal-polypyridyl complexes, elucidating their characteristics and practical
implementations through pertinent and illustrative examples in the field of
molecular electronics.
