KSC SEMINARS
ABSTRACT: Stimuli-responsive supramolecularly engineered hybrid materials either based on graphene or on organic semiconductors are key multifunctional systems for applications in (opto)electronics and energy. However, their practical use requires the optimization of the self-assembly of multimodular architectures at surfaces using non-conventional methods, their controlled manipulation and responsiveness to external stimuli, and the quantitative study of various physico-chemical properties at distinct length- and time-scales. My lecture will review our recent findings on:
(i) The harnessing of the yield of exfoliation of graphene in liquid media by mastering the supramolecular approach via the combination with ad-hoc functional molecules possessing high affinity for the graphene surface, leading ultimately to the bottom-up formation of optically responsive graphene based nanocomposites for electronics. [1]
(ii) The bottom-up formation of graphene based 3D covalent frameworks with tunable intersheet distance, exhibiting large specific surface areas which determine an ability to adsorb CO2 which is the highest reported among carbon-based materials and extremely high performance in supercapacitors.[2]
(iii) The formation of electroactive π-π stacked fibrillar structures from an amphiphilic monomolecular dyad. These fibers show unique characteristics as resistive humidity sensors combining a response rate as fast as 26 ms with an exponential growth of the current from 0 to, at least, 75% of relative humidity (RH). In this RH range the current changes up to 7 orders of magnitude, i.e. from a few pA to tens mA, demonstrating an extremely high sensitivity to humidity variations.[3]
(iv) The tailoring multicomponent films comprising photochromic systems and semiconducting molecules, and their exploitation to realise multifunctional devices such as optically switchable field-effect transistors. [4]