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At present, self-repairing, intelligent materials are being considered as future material. In this perspective, the electroactive materials are unique for their adaptability, sharp response time, control over the system, quick response rate, low power consumption, and compactness. The electroactive materials include electroactive polymers (EAPs), piezoelectric materials, electroactive gels, and fullerene compounds. The photonic interaction of light with the electroactive material converts light energy into mechanical energy and leads to multi-directional applications. Contemporarily with increased interest and emphasis on ‘green’ technological solutions, efforts are focussed on utilizing these electroactive materials with light energy. Corresponding to this, biomimetic and artificial intelligence are advancing to develop various optoelectronic devices, energy conversion and storage devices, photoresistors, vehicle components, sensors, robots, and medical devices. A better understanding of such light illumination with electroactive materials and prospective applications contributes to the planning of beneficial smart materials. Hence, this review article focusses on the interaction of light with different electroactive materials, their applications, and prospects of the current and future investigations.

The flexibility in polymer properties has allowed the development of a broad range of materials with electroactivity, such as intrinsically conductive conjugated polymers, percolated conductive composites, and ionic conductive hydrogels. These smart electroactive polymers can be designed to respond rationally under an electric stimulus, triggering outstanding properties suitable for biomedical applications. This review presents a general overview of the potential applications of these electroactive smart polymers in the field of tissue engineering and biomaterials. In particular, details about the ability of these electroactive polymers to: (1) stimulate cells in the context of tissue engineering by providing electrical current; (2) mimic muscles by converting electric energy into mechanical energy through an electromechanical response; (3) deliver drugs by changing their internal configuration under an electrical stimulus; and (4) have antimicrobial behavior due to the conduction of electricity, are discussed.

Organic electroactive materials are increasingly recognized as promising cathode materials for aqueous zinc–ion batteries (AZIBs), owing to their structural diversity and renewable nature. Despite this, the electrochemistry of these organic cathodes in AZIBs is still less than optimal, particularly in aspects such as output voltage, cyclability, and rate performance. In this review, we provide an overview of the evolutionary history of organic cathodes in AZIBs and elucidate their charge‐storage mechanisms. We then delve into the strategies to overcome the prevailing challenges faced by aqueous Zn−organic batteries, including low achievable capacity and output voltage, poor cycling stability, and rate performance. Design strategies to enhance cell performance include tailoring molecular structure, engineering electrode microstructure, and modulation of electrolyte composition. Finally, we highlight that future research directions should cover performance evaluation under practical conditions and the recycling and reuse of organic electrode materials. Organic electroactive materials, renowned for their environmental friendliness, cost‐effectiveness, and structural diversity, are currently being explored as prospective cathode materials for AZIBs. The electrochemical performance of AZIBs, including their specific capacity, output voltage, cyclability, and rate performance, can be improved by strategic design at the molecular, electrode, and electrolyte levels.

Organic electroactive materials (OEMs) offer advantages such as cost-effectiveness, environmental sustainability, and simplified end-of-life processing compared to inorganic electrode materials. Aqueous electrolytes further enhance sustainability and safety relative to organic electrolytes. Investigating the electrochemical properties of OEMs in aqueous media provides valuable insights into their redox behavior and stability under such conditions. However, challenges remain, including low electronic conductivity and structural stability concerns, while aqueous rechargeable batteries (ARBs) face inherent energy density limitations. Tetrathiafulvalene (TTF) has been previously reported as an electrode material for ARBs, while its oligomers have been proposed for organic electrolyte batteries. This study focuses on the synthesis and characterization of two new dissymmetric TTF derivatives—cyanobenzene tetrathiafulvalene pyrazine (CNB-TTF-Pz) (1) and 4-cyanobenzene tetrathiafulvalene pyrazine (4-CNB-TTF) (2)—as well as one symmetric TTF derivative, dipyrazine tetrathiafulvalene ((Pz)2-TTF) (3). Their electrochemical behavior in aqueous lithium and potassium nitrate electrolytes was systematically characterized using cyclic voltammetry. The study provides insights into the redox properties and electroactivity of these compounds, highlighting challenges related to low electronic conductivity and redox potentials close to the water stability limits. These findings contribute to broadening our understanding of the electrochemical properties of TTF derivatives in aqueous electrolytes and offer a preliminary assessment of their potential application as electrodes for ARBs.

Materials that can produce large controllable strains are widely used in shape memory devices, actuators and sensors 1 , 2 , and great efforts have been made to improve the strain output 3 – 6 . Among them, ferroelastic transitions underpin giant reversible strains in electrically driven ferroelectrics or piezoelectrics and thermally or magnetically driven shape memory alloys 7 , 8 . However, large-strain ferroelastic switching in conventional ferroelectrics is very challenging, while magnetic and thermal controls are not desirable for practical applications. Here we demonstrate a large shear strain of up to 21.5% in a hybrid ferroelectric, C 6 H 5 N(CH 3 ) 3 CdCl 3 , which is two orders of magnitude greater than that in conventional ferroelectric polymers and oxides. It is achieved by inorganic bond switching and facilitated by structural confinement of the large organic moieties, which prevents undesired 180° polarization switching. Furthermore, Br substitution can soften the bonds, allowing a sizable shear piezoelectric coefficient ( d 35 ≈ 4,830 pm V −1 ) at the Br-rich end of the solid solution, C 6 H 5 N(CH 3 ) 3 CdBr 3 x Cl 3(1− x ) . The electromechanical properties of these compounds suggest their potential in lightweight and high-energy-density devices, and the strategy described here could inspire the development of next-generation piezoelectrics and electroactive materials based on hybrid ferroelectrics. Reversible strains are widely used in high-technology systems, with piezoelectrics showing fast response but low strain. Here, ferroelectric C 6 H 5 N(CH 3 ) 3 CdCl 3 is shown to produce a strain of 21.5%, two orders of magnitude larger than other piezoelectrics, due to organic molecules preventing 180° polarization switching.

Electrochromic (EC) materials with a dark-to-transmissive switch have great applications in optical communications, infrared wavelength detectors for spacecraft, and infrared camouflage coatings. However, such electroactive materials with high stability and cyclability are rare. Considering the advantages of the donor-acceptor approach (wide-range tuneable band position) and porous two-dimensional (2D) covalent organic framework (COF, well-ordered crystalline framework with stable structure and high surface area), in this work we constructed an extended delocalised π-electron layered dark purple EC-COF-1 by reacting the donor N,N,N′,N′-tetrakis( p -aminophenyl)- p -benzenediamine (TPBD) with the acceptor 2,1,3-benzothiadiazole-4,7-dicarboxaldehyde (BTDD). A sandwiched device made of EC-COF-1 exhibits the two-band bleaching (370 nm and 574 nm) in the visible region and becomes transparent under the applied potential with an induced absorption centring at 1400 nm. This discovery of a stable dark-to-transmissive switch in COF might open another door for their application in many EC devices for various purposes. Electrochromic materials are important for different optical applications but often these materials show low stability. Here, the authors demonstrate a stable donor-acceptor covalent organic framework which shows a stable dark-to-transmissive switching behaviour.

Long-term stability and high-rate capability have been the major challenges of sodium-ion batteries. Layered electroactive materials with mechanically robust, chemically stable, electrically and ironically conductive networks can effectively address these issues. Herein we have successfully directed carbon nanofibers to vertically penetrate through graphene sheets, constructing robust carbon nanofiber interpenetrated graphene architecture. Molybdenum disulfide nanoflakes are then grown in situ alongside the entire framework, yielding molybdenum disulfide@carbon nanofiber interpenetrated graphene structure. In such a design, carbon nanofibers prevent the restacking of graphene sheets and provide ample space between graphene sheets, enabling a strong structure that maintains exceptional mechanical integrity and excellent electrical conductivity. The as-prepared sodium ion battery delivers outstanding electrochemical performance and ultrahigh stability, achieving a remarkable specific capacity of 598 mAh g −1 , long-term cycling stability up to 1000 cycles, and an excellent rate performance even at a high current density up to 10 A g −1 . Here the authors construct carbon nanofiber interpenetrated graphene architecture with in-situ grown MoS 2 nanoflakes alongside the framework. The design combines exceptional mechanical integrity and excellent electronic conductivity, enabling outstanding electrochemical performance in sodium-ion battery.

Stretchable energy storage devices, maintaining the capability of steady operation under large mechanical strain, have become increasing more important with the development of stretchable electronic devices. Stretchable supercapacitors (SSCs), with high power density, modest energy density, and superior mechanical properties are regarded as one of the most promising power supplies to stretchable electronic devices. Conductive polymers, such as polyaniline (PANI), polypyrrole (PPy), polythiophene (PTh) and poly(3,4-ehtylenedioxythiophene) (PEDOT), are among the well-studied electroactive materials for the construction of SSCs because of their high specific theoretical capacity, excellent electrochemical activity, light weight, and high flexibility. Much effort has been devoted to developing stretchable, conductive polymer-based SSCs with different device structures, such as sandwich-type and fiber-shaped type SSCs. This review summarizes the material and structural design for conductive polymer-based SSCs and discusses the challenge and important directions in this emerging field.

Hydrogen peroxide produced by electrochemical oxygen reduction reaction provides a potentially cost effective and energy efficient alternative to the industrial anthraquinone process. In this study, we demonstrate that by modulating the oxygen functional groups near the atomically dispersed cobalt sites with proper electrochemical/chemical treatments, a highly active and selective oxygen reduction process for hydrogen peroxide production can be obtained in acidic electrolyte, showing a negligible amount of onset overpotential and nearly 100% selectivity within a wide range of applied potentials. Combined spectroscopic results reveal that the exceptionally enhanced performance of hydrogen peroxide generation originates from the presence of epoxy groups near the Co–N 4 centers, which has resulted in the modification of the electronic structure of the cobalt atoms. Computational modeling demonstrates these electronically modified cobalt atoms will enhance the hydrogen peroxide productivity during oxygen reduction reaction in acid, providing insights into the design of electroactive materials for effective peroxide production. The production of hydrogen peroxide by electrochemical oxygen reduction is an attractive alternative to the industrial process, but catalysts should be optimized. Here, the authors enhance hydrogen peroxide production in acidic media with epoxy groups near cobalt centers on carbon nanotubes.

Potassium-ion batteries (PIBs) are appealing alternatives to conventional lithium-ion batteries (LIBs) because of their wide potential window, fast ionic conductivity in the electrolyte, and reduced cost. However, PIBs suffer from sluggish K + reaction kinetics in electrode materials, large volume expansion of electroactive materials, and the unstable solid electrolyte interphase. Various strategies, especially in terms of electrode design, have been proposed to address these issues. In this review, the recent progress on advanced anode materials of PIBs is systematically discussed, ranging from the design principles, and nanoscale fabrication and engineering to the structure-performance relationship. Finally, the remaining limitations, potential solutions, and possible research directions for the development of PIBs towards practical applications are presented. This review will provide new insights into the lab development and real-world applications of PIBs.