Functionalized Carbon Nanotube Networks with Field-Tunable Bandgaps

An electrochemical cell with a hydrogen-containing PEG electrolyte is integrated in the gate of a CNT-based transistor to modify the CNT structures and bandgaps. CNTs in the transistor channel can be functionalized by electrochemical hydrogenation driven by gate voltages, which tunes CNT bandgaps continuously and reversibly to nonvolatile analog values between 0 and 3.2 eV. The CNT transistors with the flexibly tunable bandgaps are of both scientific and technical interest in analog memory, field programmable, neuromorphic, photonic, and photovoltaic devices and circuits.