Reversible Light-Responsive Solventless-Liquid Switch: Polarization-Induced Dynamic Surface Ordering–Disordering in Liquid-Like Carbon Quantum Dots

Abstract

Naturally stimulated dynamic ordering−disordering of biomolecules via noncovalent interactions is a commonly occurring phenomenon in biological systems. Herein, we report the effect of induced polarization on the charge carrier dynamics of carbon-quantum-dot-based nano ionic materials (CQD-NIMs) under simulated solar radiation. The solventless liquid-like CQD-NIMs is composed of polystyrenesulfonate (PSS)-passivated CQD as the core−corona system with a polyetheramine (Jeffamine) forming the canopy. The material was observed to behave as a dielectric when placed between two electrodes. Dynamic ordering−disordering of the corona around the CQD surface under induced polarization allowed excess current flow through the solventless material when exposed to simulated solar radiation. Such reversible molecular-assembly-induced photoconducting behavior of the CQDs was characterized with impedance spectroscopy and steady state fluorescence spectroscopy. The concept depicted in the present manuscript may be further developed to design smart light-sensitive molecular switching devices.