Gelatinous underwater invertebrates such as jellyfish have organs that are transparent, luminescent and self-healing, which allow the creatures to navigate, camouflage themselves and, indeed, survive ...in aquatic environments. Artificial luminescent materials that can mimic such functionality can be used to develop aquatic wearable/stretchable displays and water-resistant devices. Here, a luminescent composite that is simultaneously transparent, tough and can autonomously self-heal in both dry and wet conditions is reported. A tough, self-healable fluorine elastomer with dipole-dipole interactions is synthesized as the polymer matrix. It exhibits excellent compatibility with metal halide perovskite quantum dots. The composite possesses a toughness of 19 MJ m
, maximum strain of 1300% and capability to autonomously self-heal underwater. Notably, the material can withstand extremely harsh aqueous conditions, such as highly salty, acidic (pH = 1) and basic (pH = 13) environment for more than several months with almost no decay in mechanical performance or optical properties.
Ligaments are flexible and stiff tissues around joints to support body movements, showing superior toughness and fatigue-resistance. Such a combination of mechanical properties is rarely seen in ...synthetic elastomers because stretchability, stiffness, toughness, and fatigue resistance are seemingly incompatible in materials design. Here we resolve this long-standing mismatch through a hierarchical crosslinking design. The obtained elastomer can endure 30,000% stretch and exhibit a Young's modulus of 18 MPa and toughness of 228 MJ m
, outperforming all the reported synthetic elastomers. Furthermore, the fatigue threshold is as high as 2,682 J m
, the same order of magnitude as the ligaments (~1,000 J m
). We reveal that the dynamic double-crosslinking network composed of Li
-O interactions and PMMA nanoaggregates allows for a hierarchical energy dissipation, enabling the elastomers as artificial ligaments in soft robotics.
Dielectric elastomer actuators (DEAs) with large actuation strain and high energy density are highly desirable for actuating soft robots. However, DEAs usually require high driving electric fields ...(>100 MV m
) to achieve high performances due to the low dielectric constant and high stiffness of dielectric elastomers (DEs). Here, we introduce polar fluorinated groups and nanodomains aggregated by long alkyl side chains into DE design, simultaneously endowing DE with a high dielectric constant and desirable modulus. Our DE exhibits a maximum area strain of 253% at a low driving electric field of 46 MV m
. Notably, it achieves an ultrahigh specific energy of 225 J kg
at only 40 MV m
, around 6 times higher than natural muscle and twice higher than the state-of-the-art DE. Using our DE, soft robots reach an ultrafast running speed of 20.6 BL s
, 60 times higher than that of commercial VHB 4910, representing the fastest DEA-driven soft robots ever reported.
Flexible bioelectronics have attracted increasing research interests due to their wide range of potential applications in human motion detection, personal healthcare monitoring, and medical ...diagnosis. Recently, design and fabrication strategies integrated with mussel‐inspired polydopamine (PDA) have demonstrated many appealing properties, which meet the structural and functional requirements of high‐performance flexible bioelectronics. The inherent multiple reactive sites and hierarchical interactions within PDA can promote the total electrochemical activities, self‐healing, surface activation, and biocompatibility of the composite system. This review paper strives to provide a comprehensive overview on this emerging area, including the fabrication methodology, the structural and functional contributions of PDA on the whole composites, and various applications of PDA‐based flexible bioelectronics. The current challenges and future outlook in this field are also extensively discussed at the end. This paper aims to serve as a guideline in this emerging area and provide new inspirations toward next‐generation integrated multifunctional flexible PDA bioelectronics with a broad range of healthcare applications.
This review strives to summarize the recent advances and highlights of flexible polydopamine bioelectronics by focusing on their chemical structures, fabrication methods, working mechanisms as well as various applications ranging from flexible biosensors, implantable devices to neuromorphic devices.
In recent years, both natural melanin and their synthetic analogs have attracted increasing attention as an emerging class of bioinspired supercapacitor materials, due to their rich sources, ...excellent processability, and extraordinary electrochemical performances. Particularly, the inherent heteroatoms and catechol groups within natural melanin and polydopamine (PDA) nanomaterials can promote the total electrochemical activities and surface activation capabilities of the systems. This review strives to summarize the recent advances and highlights of melanin-inspired supercapacitors by focusing on their chemical structures, fabrication methods, working mechanisms as well as various applications ranging from wearable devices, flexible capacitors to supercapacitor separators. Finally, the current challenges of melanin-inspired supercapacitor systems, and future perspectives in the rational fabrication of the new generation of bioinspired supercapacitors are also closely discussed.
This review paper strives to summarize the recent advances and highlights of melanin-inspired supercapacitors by focusing on their chemical structures, fabrication methods, working mechanisms as well as various applications ranging from wearable devices, flexible capacitors to supercapacitor separators.
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•The chemical structures and working mechanisms of melanin-inspired supercapacitors were systematically summarized.•The representative strategies for the fabrication of melanin-inspired supercapacitors were presented.•Various applications ranging from wearable devices, flexible capacitors to supercapacitor separators were highlighted.•The current challenges and perspectives on the future research directions were closely discussed.
Rapid underwater self‐healing elastomers with high mechanical strength at ambient temperature are highly desirable for dangerous underwater operations. However, current room temperature self‐healing ...materials have shortcomings, such as low healing strength (below megapascal), long healing time (hours), and decay of healing functions in harsh environments (salty, acidic, and basic solutions), limiting their practical applications. Herein, it is introduced water‐stable Debye forces and high‐density nano‐sized physical crosslinking into one network to achieve a stiff yet rapid self‐healing elastomer that can work in harsh aqueous environments. The obtained elastomer possesses a high Young's modulus of 48 MPa (24 times than that of natural elastomer), and it can achieve 90% of maximum mechanical strength healing for 10 s at ambient temperature in all types of harsh aqueous conditions, outperforming three orders of magnitudes in healing speed of reported room‐temperature self‐healing elastomers with Young's modulus over 10 MPa. The new stiff yet rapidly healable elastomers have great potential in emergent repair in urgent and dangerous cases.
A stiff PBMA‐PEA rubber (≈48 MPa) with rapid self‐healing capability (achieve 90% of maximum mechanical strength healing for 10 s) is obtained by incorporating high‐density nano‐sized physical crosslink and water‐stable Debye forces, which have great potential in emergent repair in urgent and dangerous cases. A novel aqueous self‐healing mechanism, which is unaffected by acids, bases, and salts, is also proposed.
LiNO3 is a remarkable additive that can dramatically enhance the stability of ether‐based electrolytes at lithium metal anodes. However, it has long been constrained by its incompatibility with ...commercially used ester electrolytes. Herein, we correlated the fundamental role of entropy with the limited LiNO3 solubility and proposed a new low‐entropy‐penalty design that achieves high intrinsic LiNO3 solubility in ester solvents by employing multivalent linear esters. This strategy is conceptually different from the conventional enthalpic methods that relies on extrinsic high‐polarity carriers. In this way, LiNO3 can directly interact with the primary ester solvents and fundamentally alters the electrolyte properties, resulting in substantial improvements in lithium‐metal batteries with high Coulombic efficiency and cycling stability. This work illustrates the significance of regulating the solvation entropy for high‐performance electrolyte design.
We correlated the fundamental role of entropy with the limited LiNO3 solubility in ester electrolytes and proposed a new multivalent low‐entropy‐penalty design to achieve intrinsic LiNO3 solubilization. Linear esters with higher multivalency leads to more stable solvation structures and a monotonic increase in LiNO3 solubility of up to 0.8 M. Our findings offer new fundamental insights into the LiNO3 solvation chemistry.
Abstract Stretchable dielectric polymer with high dielectric constant is a major component for electroluminescent devices. However, the intrinsic instability toward water severely limits their ...further applications in marine environment. Here, a transparent, underwater stable, and self‐healable dielectric material with high dielectric constant is reported. The electroluminescent device based on this newly designed fluoropolymer can work stably in aqueous conditions. There is no significant attenuation of mechanical and optoelectronic property after immersed in water and salty water for a month. The intrinsic self‐healing ability of the device makes it robust and resilient against unexpected minor or severe damages.
Dynamic supramolecular networks are constantly accompanied by thermal instability. The fundamental reason is most reversible noncovalent bonds quickly decay at elevated temperatures and dissociate ...below 100 °C. Here, in this paper, we realize a reversible ion–dipole interaction with high-temperature stability exceeding 150 °C. The resultant supramolecular network can simultaneously possess mechanical strength of 1.32 MPa (14.8 times that of pristine material), dynamic self-healing capability, and a stable working temperature of up to 200 °C. From the prolonged characteristic relaxation time of 600 s even at 100 °C, our material represents one of the most thermally stable dynamic supramolecular polymers. These remarkable performances are achieved by using a new multivalent yet low-entropy-penalty molecular design. In this way, the noncovalent bond can reach a high enthalpy while minimizing the entropy-dominated thermal dissociations.
Energy‐free thermal regulation is in great demand nowadays. Thermochromic materials are widely explored and used in smart windows. However, most thermochromic materials have fixed transition ...temperature and still suffer from poor stability. To overcome this challenge, a thermochromic polymer coating based on ion–dipole interaction with switchable transition temperature, high stability toward several harsh environments, self‐healing, and radiative cooling property is developed. It can continuously tune from transparent to opaque according to the temperature change. The lower critical transition temperature can be tuned from 33 to 43 °C by simply adjusting the composition of ionic liquids. Owing to the fluorine polymer backbone and dynamic ion–dipole interactions, it can also keep stable in aquatic, −20 °C, and 70 °C environments and self‐heal upon damage thus prolonging its working life for real applications.
A thermochromic polymer coating with switchable transition temperature is successfully prepared based on ion–dipole interactions between fluorinated polymer and ionic liquid. The reversibly and continuously phase‐change behavior makes it achieve efficient energy‐saving cooling and heating in different seasons. Owing to the fluorine polymer backbone and dynamic interactions, it can keep stable in harsh environments and self‐heal upon damage thus prolonging its working life for real applications.
