Peptide-based novel small molecules and polymers: unexplored optoelectronic materials

In recent times, optoelectronic materials have become emerging technology and several designs have been established to overcome the past failures and desire for new efficient devices. Numerous analyses employing imidazole, carbazole, triphenylamine, phosphine oxide, squaraine, BODIPY, dithienosilole, dithienogermole, and fullerene/non-fullerene derivatives have been developed in different donor-acceptor combinations with the inclusion of pi/spacer conjugations. Most of these designs are constructed by organic, organometallic, and solid-state (or hybrids) to improve the external quantum yield, lifetime, and color saturation. Recently, few bio-molecular materials (peptide-conjugated) have attracted attention due to the screening of their electronic and luminous properties. Peptide-based conjugate molecules are a promising class of soft materials, which are currently gaining importance among the material community due to a wide range of applications (protein therapeutics, drug delivery, optoelectronics, and catalysis). However, peptide-based materials are currently a focused area of study since inadequate results are available and it is required to increase interest in the field with peptides as the main focus in optoelectronics. The current review explains optoelectronic materials based on peptides moieties, which have unexplored applications due to fewer reports on them. In optoelectronics, photovoltaics (solar cells), organic light-emitting diodes (OLEDs), thin-film transistors, and electrochromism have been discussed. Photoactive materials design based on the donor and acceptor concept has been presented and discussed. This evaluation contributes to the materialistic properties of the peptides for electro-optic applications and their design strategy along with the current status. The discussion on the future perspectives of optoelectronics via peptide-based materials will certainly give an insight into the new upcoming trends.