Conjugated polymers with various electron-donor (D) and -acceptor (A) structures present diverse electrochemical, optical–physical and EC properties.

Electrochromic (EC) materials and devices, whose optical properties (color, reflectance, emittance, etc.) can be manipulated by switching to a low-voltage bias, show great promise in many applications such as smart windows, adaptive military camouflage, displays, and anti-glare rearview mirrors. In recent years, EC materials and devices for camouflage, including color camouflage and thermal camouflage, have attracted growing attention and research interest due to their many attractive properties such as rapid response, controllable optical modulation, low energy consumption (bistability), and flexibility. Despite the continuous development of related fields, the design and fabrication of EC devices that truly meet the requirements of camouflage applications still face tremendous challenges. Herein, in this review, we first briefly introduce the structures and main performance parameters of EC devices for camouflage. Then we comprehensively summarize the latest research progress of EC technology in the camouflage field from the aspects of color camouflage and thermal camouflage. Finally, the current challenges and future perspectives in the EC camouflage field are proposed and discussed. It is our hope that this review will accelerate the development of these promising EC materials and devices and provide guidance for developing mature camouflage devices.

An intriguing bifunctional electrode of self-supported hollow (Ni,Co)Se₂arrays was facilely synthesized with a metal–organic framework (MOF) precursor.

A donor–acceptor (D–A) cruciform conjugated luminophore DMCS-TPA was designed and synthesized. The DMCS-TPA solid shows both aggregation induced emission (AIE) effect and high contrast mechanochromic (MC) behavior with a remarkable spectral shift of 87 nm. The obvious fluorescence switching from yellowish green to orange can be realized by pressing at only 10 MPa or simply grinding. The photophysical properties, theory calculation and XPS results demonstrate that the extension of the conjugation length and subsequent enhancement of intramolecular charge transfer (ICT) transition are responsible for the improved MC performance. In addition, DMCS-TPA is readily deposited on the ITO electrode surface by the electrochemical method to form an electrochromic (EC) film with multiple colours showing (light green at 0 V, red at 1 V, grey at 1.1 V and blue at 1.45 V) and a high optical contrast of 65% at 769 nm. The results suggest that incorporation of electroactive moieties into luminophores to constitute D–A cruciform conjugated structures is a promising design strategy for preparing dual functional materials combining MC and EC properties.