Transparency-switchable actuator based on aligned carbon nanotube and paraffin-polydimethylsiloxane composite

Abstract

High-performance actuators have been studied for many years, as they can be used in the fields of artificial muscles, optical switches and biomimetic applications. However, previous actuators mostly had single colors. Actuators with switchable optical properties are still rare. Here, we propose a transparency-switchable actuator based on single-layer superaligned carbon nanotube sheet and paraffin-polydimethylsiloxane composite. When a voltage is applied, the transmittance of the actuator changes from 0.7% to 67% (at the wavelength of 550 nm). At the same time, it bends obviously with a displacement up to 8.4 mm. The actuator is also durable, demonstrating both reversible actuation phenomenon and repeatable switchable transparency for 100 cycles. In addition, since this new type of actuator demonstrates optical property changing together with actuation process, which is smarter compared to previous conventional actuators, a smart window is fabricated, indicating its application in personal privacy protection and intelligent household devices. In a word, this work opens new perspectives on smart windows, optical switches and so on.