Xiaoyuan Ma1
Boston University1
Electrochromic (EC) materials show great promise as one of the key functional components in future internet-of-things (IoT) applications such as flexible/3D displays, optical camouflage, smart windows, and smart sensor systems. However, realizing flexible EC devices with high energy-efficiency and fast switching speed is fundamentally challenging. This research is to investigate the in-situ oxidation of MXenes for two-dimensional (2D) transition metal oxides (TMOs) and develop the TMO/MXene heterostructures as building blocks for next generation 2D materials based electronic devices. Though the TMOs thin films have been fabricated for a long time using various methods such as sol-gel coating, pulsed laser deposition, and radio-frequency (RF) sputtering, the films are composed of bulky agglomerates which are rigid and usually over hundreds of nanometers thick. Such form of the TMOs is not suitable for the desired electronic devices which are flexible and could be integrated with other 2D materials. Here we demonstrate fast, and high-coloration-efficiency EC devices based on self-assembled 2D V<sub>2</sub>O<sub>5</sub>/MXene heterostructure, while the liquid/liquid interfacial self-assembly (LLIA) technique was used to fabricate the heterostructure. With the expectation of low contact resistance between the 2D TMO and MXenes, we further demonstrate the high-performance EC devices based on such heterostructures.