Exploring Tetrathiafulvalene-Carbon Nanodots Conjugates in Charge Transfer Reactions

Abstract

Carbon nanodots (CNDs) have been synthesized using low-cost and biocompatible starting materials such as citric acid/urea, under microwave irradiation and constant pressure conditions. The obtained pressure synthesized CNDs (pCND) were covalently modified with photo- and electro-active π-extended tetrathiafulvalene (exTTF) by means of a two-step esterification reaction affording pCND-exTTF. The electronic interactions between the CNDs and exTTF were investigated in the ground and excited states. Ultrafast pump-probe experiments assisted in corroborating that charge separation governs the deactivation of photoexcited pCND-exTTF. These size-regular structures, as revealed by AFM, are stable electron donor-acceptor conjugates of interest for a better understanding of basic processes such as artificial photosynthesis, catalysis and photovoltaics, involving readily available fluorescent nanodots.