With the booming development of flexible and wearable electronics, their safety issues and operation stabilities have attracted worldwide attentions. Compared with traditional liquid electrolytes, ...gel polymer electrolytes (GPEs) are preferred due to their higher safety and adaptability to the design of flexible energy storage devices. This review summarizes the recent progress of GPEs with enhanced physicochemical properties and specified functionalities for the application in electrochemical energy storage. Functional GPEs that are capable to achieve unity lithium‐ion transference number and offer additional pseudocapacitance to the overall capacitance are carefully discussed. The smart GPEs with self‐protection, thermotolerant, and self‐healing abilities are particularly highlighted. To close, the future directions and remaining challenges of the GPEs for application in electrochemical energy storages are summarized to provide clues for the following development.
Gel polymer electrolytes represent an attractive alternative to liquid electrolytes due to the superiorities of higher safety, better flexibility, and higher workability, which are promising for the use in electrochemical energy storage for the next‐generation flexible and wearable electronics. Their recent advancements, challenges, and perspectives are highlighted to provide guidance for the future study.
The construction of lightweight, flexible and stretchable power systems for modern electronic devices without using elastic polymer substrates is critical but remains challenging. We have developed a ...new and general strategy to produce both freestanding, stretchable, and flexible supercapacitors and lithium‐ion batteries with remarkable electrochemical properties by designing novel carbon nanotube fiber springs as electrodes. These springlike electrodes can be stretched by over 300 %. In addition, the supercapacitors and lithium‐ion batteries have a flexible fiber shape that enables promising applications in electronic textiles.
My flexible friend: Springlike electrodes with remarkable electrochemical properties have been used to create flexible and stretchable fiber‐shaped supercapacitors and lithium‐ion batteries. The electrodes, which are made from twisted aligned multiwalled carbon nanotubes (see picture), can be stretched by over 300 %, and the devices show stable performance under bending and stretching deformations.
A Shape-Memory Supercapacitor Fiber Deng, Jue; Zhang, Ye; Zhao, Yang ...
Angewandte Chemie (International ed.),
December 14, 2015, Letnik:
54, Številka:
51
Journal Article
Recenzirano
A shape‐memory, fiber‐shaped supercapacitor is developed by winding aligned carbon nanotube sheets on a shape‐memory polyurethane substrate. Despite its flexibility and stretchability, the deformed ...shapes under bending and stretching can be “frozen” as expected and recovered to the original state when required. Its electrochemical performances are well‐maintained during deformation, at the deformed state and after the recovery.
A smart supercapacitor: A shape‐memory supercapacitor was developed by winding carbon nanotube sheets on a shape‐memory polyurethane substrate (see picture). Its electrochemical performances are well maintained during deformation, at the deformed state and after the recovery.
Energy storage devices, such as lithium‐ion batteries and supercapacitors, are required for the modern electronics. However, the intrinsic characteristics of low power densities in batteries and low ...energy densities in supercapacitors have limited their applications. How to simultaneously realize high energy and power densities in one device remains a challenge. Herein a fiber‐shaped hybrid energy‐storage device (FESD) formed by twisting three carbon nanotube hybrid fibers demonstrates both high energy and power densities. For the FESD, the energy density (50 mWh cm−3 or 90 Wh kg−1) many times higher than for other forms of supercapacitors and approximately 3 times that of thin‐film batteries; the power density (1 W cm−3 or 5970 W kg−1) is approximately 140 times of thin‐film lithium‐ion battery. The FESD is flexible, weaveable and wearable, which offers promising advantages in the modern electronics.
Strand and deliver: A fiber‐shaped hybrid energy‐storage device is created by twisting three different carbon nanotube hybrid fibers together to integrate the properties of a lithium‐ion battery and a supercapacitor. The twisted strands give rise to both high energy and power densities. The hybrid device is three‐dimensionally flexible, weaveable, and wearable, which offers promising advantages in modern electronics.
Denitrification and anaerobic ammonium oxidization (anammox) are considered the most important processes of removing reactive nitrogen from natural aquatic environments. We measured and compared in ...situ rates of the two processes across the sediment–water interface of Jinpu Bay using continuous-flow experiments combined with a¹⁵NO₃⁻tracing technique to determine their relative importance in this hypereutrophic coastal ecosystem. Rates of denitrification and anammox ranged from 1.76 to 327.97 and 0.33 to 36.32 μmol N m⁻² day⁻¹, respectively. Both the denitrification and anammox processes were observed to be associated closely with the bioavailability of organic matter and concentrations of sulfide and iron oxides in sediments. Denitrification was the dominant pathway of eliminating reactive nitrogen and on average accounted for about 90 % of the total removed nitrogen. Totally, both the denitrification and anammox processes removed about 20 % of the externally derived inorganic nitrogen within the system. Most of the external nitrogen was still retained in the ecosystem, which may cause the severe eutrophication and algae blooms occurring at the study area.
This study investigated environmental influences on inorganic nitrogen exchange at the sediment–water interface and quantified the function of sediment as inorganic nitrogen sink/source in the ...eastern Chongming tidal flat of the Yangtze Estuary. Intact sediment cores (20–25 cm deep) were collected from the high, middle and low tidal flats of the study area every 2 months from July 2012 to May 2013, and incubated to measure the fluxes of ammonium and nitrate (plus nitrite) across the sediment–water interface via continuous-flow experiments. The incubation experimental results showed that ammonium was mainly released from the sediment into the overlying water, with a flux of −5.91 to 14.44 mmol m⁻² day⁻¹. In contrast, nitrate was primarily influxed from the overlying water into the sediment, with a flux of −20.09 to 8.72 mmol m⁻² day⁻¹. In this work, temperature, salinity, sedimentary ammonium and nitrate, and total organic carbon were observed to significantly affect the dynamic exchange of inorganic nitrogen across the sediment–water interface of the study area, via controlling nitrogen transformation processes in sediments. It was also estimated that ca. 2101 t N year⁻¹ for ammonium was totally released from the sediment to overlying water while ca. 1577 t N year⁻¹ for nitrate was removed from the water to sediment. The dynamic exchanges of inorganic nitrogen at the sediment–water interface implied that the sediment has important influence on adjusting the levels of ammonium and nitrate in tidal water of the study area.
The Li–air battery represents a promising power candidate for future electronics due to its extremely high energy density. However, the use of Li–air batteries is largely limited by their poor ...cyclability in ambient air. Herein, Li–air batteries with ultralong 610 cycles in ambient air are created by combination of low‐density polyethylene film that prevents water erosion and gel electrolyte that contains a redox mediator of LiI. The low‐density polyethylene film can restrain the side reactions of the discharge product of Li2O2 to Li2CO3 in ambient air, while the LiI can facilitate the electrochemical decomposition of Li2O2 during charging, which improves the reversibility of the Li–air battery. All the components of the Li–air battery are flexible, which is particularly desirable for portable and wearable electronic devices.
Li–air batteries with ultralong 610 cycles in ambient air are achieved by combination of low‐density polyethylene film that prevents water erosion and gel electrolyte that contains a redox mediator of LiI. All the components of the Li–air battery are also flexible, which is promising for various fields such as portable and wearable electronics.
A novel fiber-shaped supercapacitor is created with high volumetric energy density by designing an asymmetric configuration and integrating multiple functional components for electrodes. More ...specifically, a ternary hybrid fiber is prepared as a positive electrode by growing MnO2 nanosheets onto a conducting polymer-coated carbon nanotube fiber; an ordered microporous carbon/carbon nanotube hybrid fiber is made as a negative electrode; and the hybrid positive and negative fibers are assembled into a fiber-shaped asymmetric supercapacitor. It shows a high operating voltage of 1.8 V, compared with 0.8–1.0 V of their conventional counterparts based on aqueous gel electrolytes; in particular, it produces an energy density as high as 11.3 mWh/cm3 which is on par with the thin-film lithium-ion batteries. It also exhibits remarkable cyclic stability and good rate performance. Due to the unique fiber shape, it can be woven or knitted into flexible power textiles.
Electricity generation from flowing water has been developed for over a century and plays a critical role in our lives. Generally, heavy and complex facilities are required for electricity ...generation, while using these technologies for applications that require a small size and high flexibility is difficult. Here, we developed a fluidic nanogenerator fiber from an aligned carbon nanotube sheet to generate electricity from any flowing water source in the environment as well as in the human body. The power conversion efficiency reached 23.3 %. The fluidic nanogenerator fiber was flexible and stretchable, and the high performance was well‐maintained after deformation over 1 000 000 cycles. The fiber also offered unique and promising advantages, such as the ability to be woven into fabrics for large‐scale applications.
Energy from flowing water: A new family of fiber‐shaped fluidic nanogenerators based on a sheet of aligned carbon nanotubes is created. A power conversion efficiency of 23.3 % is achieved by using the stable and durable nanogenerator. Its structure and performance can be well‐maintained even after 1 000 000 cycles of deformation.
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