The increasing demands to further electrify and digitalize our society set demands for a green electrical energy storage technology that can be scaled between very small,and heavily distributed electrical energy sourc...The increasing demands to further electrify and digitalize our society set demands for a green electrical energy storage technology that can be scaled between very small,and heavily distributed electrical energy sources,to very large volumes.Such technology must be compatible with fast-throughput,large-volume and low-cost fabrication processes,such as using printing and coating techniques.Here,we demonstrate a sequential production protocol to fabricate supercapacitors including electrodes based on cellulose nanofibrils(CNF)and the conducting polymer PEDOT:PSS.Thin and lightweight paper electrodes,carbon adhesion layers and the gel electrolyte are fabricated using spray coating,screen printing,and bar coating,respectively.These all solid-state supercapacitors are flexible,mechanically robust and exhibit a low equivalent series resistance(0.22Ω),thus resulting in a high power density(∼104 W/kg)energy technology.The supercapacitors are combined and connected to a power management circuit to demonstrate a smart packaging application.This work shows that operational and embedded supercapacitors can be manufactured in a manner to allow for the integration with,for instance smart packaging solutions,thus enabling powered,active internet-of-things(IoT)devices in a highly distributed application.展开更多
Laser-induced graphitization(LIG)is a method of converting a carbon-rich precursor into a highly conductive graphite-like carbon by laser scribing.This method has shown great promise as a versatile and low-cost patter...Laser-induced graphitization(LIG)is a method of converting a carbon-rich precursor into a highly conductive graphite-like carbon by laser scribing.This method has shown great promise as a versatile and low-cost patterning technique.Here we show for the first time how an ink based on cellulose and lignin can be patterned using screen printing followed by laser graphitization.Screen printing is one of the most commonly used manufacturing techniques of printed electronics,making this approach compatible with existing processing of various devices.The use of forest-based materials opens the possibility of producing green and sustainable electronics.Pre-patterning of the ink enables carbon patterns without residual precursor between the patterns.We investigated the effect of the ink composition,laser parameters,and additives on the conductivity and structure of the resulting carbon and could achieve low sheet resistance of 3.8Ωsq^(−1) and a high degree of graphitization.We demonstrated that the process is compatible with printed electronics and finally manufactured a humidity sensor which uses lignin as the sensing layer and graphitized lignin as the electrodes.展开更多
Heat sensors form an important class of devices that are used across multiple fields and sectors.For applications such as electronic skin and health monitoring,it is particularly advantageous if the output electronic ...Heat sensors form an important class of devices that are used across multiple fields and sectors.For applications such as electronic skin and health monitoring,it is particularly advantageous if the output electronic signals are not only high,stable,and reproducible,but also self-generated to minimize power consumption.Here,we present an ultrasensitive heat sensing concept that fulfills these criteria while also being compatible with scalable low-cost manufacturing on flexible substrates.The concept resembles a traditional thermocouple,but with separated electrodes bridged by a gel-like electrolyte and with orders of magnitudes higher signals(around 11 mV K^(−1)).The sensor pixels provide stable and reproducible signals upon heating,which,for example,could be used for heat mapping.Further modification to plasmonic nanohole metasurface electrodes made the sensors capable of also detecting light-induced heating.Finally,we present devices on flexible substrates and show that they can be used to detect human touch.展开更多
Materials that provide dynamically tunable infrared(IR)response are important for many applications,including active camouflage and thermal management.However,current IR-tunable systems often exhibit limitations in me...Materials that provide dynamically tunable infrared(IR)response are important for many applications,including active camouflage and thermal management.However,current IR-tunable systems often exhibit limitations in mechanical properties or practicality of their tuning modalities,or require complex and costly fabrication methods.An additional challenge relates to providing compatibility between different spectral channels,such as allowing an object to be reversibly concealed in the IR without making it appear in the visible range.Here,we demonstrate that conducting polymer-cellulose papers,fabricated through a simple and cheap approach,can overcome such challenges.The papers exhibit IR properties that can be electrochemically tuned with large modulation(absolute emissivity modulation of 0.4)while maintaining largely constant response in the visible range.Owing to high ionic and electrical conductivity,the tuning of the top surface can be performed electrochemically from the other side of the paper even at tens of micrometer thicknesses,removing the need for overlaying electrode and electrolyte in the optical beam path.These features enabled a series of electrically tunable IR devices,where we focus on demonstrating dynamic radiative coolers,thermal camouflage,anti-counterfeiting tags,and grayscale IR displays.The conducting polymer-cellulose papers are sustainable,cheap,flexible and mechanically robust,providing a versatile materials platformfor active and adaptive IR optoelectronic devices.展开更多
文摘The increasing demands to further electrify and digitalize our society set demands for a green electrical energy storage technology that can be scaled between very small,and heavily distributed electrical energy sources,to very large volumes.Such technology must be compatible with fast-throughput,large-volume and low-cost fabrication processes,such as using printing and coating techniques.Here,we demonstrate a sequential production protocol to fabricate supercapacitors including electrodes based on cellulose nanofibrils(CNF)and the conducting polymer PEDOT:PSS.Thin and lightweight paper electrodes,carbon adhesion layers and the gel electrolyte are fabricated using spray coating,screen printing,and bar coating,respectively.These all solid-state supercapacitors are flexible,mechanically robust and exhibit a low equivalent series resistance(0.22Ω),thus resulting in a high power density(∼104 W/kg)energy technology.The supercapacitors are combined and connected to a power management circuit to demonstrate a smart packaging application.This work shows that operational and embedded supercapacitors can be manufactured in a manner to allow for the integration with,for instance smart packaging solutions,thus enabling powered,active internet-of-things(IoT)devices in a highly distributed application.
基金We would like to acknowledge funding from Vinnova for the Digital Cellulose Competence Center(DCC),Diary number 2016-05193.
文摘Laser-induced graphitization(LIG)is a method of converting a carbon-rich precursor into a highly conductive graphite-like carbon by laser scribing.This method has shown great promise as a versatile and low-cost patterning technique.Here we show for the first time how an ink based on cellulose and lignin can be patterned using screen printing followed by laser graphitization.Screen printing is one of the most commonly used manufacturing techniques of printed electronics,making this approach compatible with existing processing of various devices.The use of forest-based materials opens the possibility of producing green and sustainable electronics.Pre-patterning of the ink enables carbon patterns without residual precursor between the patterns.We investigated the effect of the ink composition,laser parameters,and additives on the conductivity and structure of the resulting carbon and could achieve low sheet resistance of 3.8Ωsq^(−1) and a high degree of graphitization.We demonstrated that the process is compatible with printed electronics and finally manufactured a humidity sensor which uses lignin as the sensing layer and graphitized lignin as the electrodes.
文摘Heat sensors form an important class of devices that are used across multiple fields and sectors.For applications such as electronic skin and health monitoring,it is particularly advantageous if the output electronic signals are not only high,stable,and reproducible,but also self-generated to minimize power consumption.Here,we present an ultrasensitive heat sensing concept that fulfills these criteria while also being compatible with scalable low-cost manufacturing on flexible substrates.The concept resembles a traditional thermocouple,but with separated electrodes bridged by a gel-like electrolyte and with orders of magnitudes higher signals(around 11 mV K^(−1)).The sensor pixels provide stable and reproducible signals upon heating,which,for example,could be used for heat mapping.Further modification to plasmonic nanohole metasurface electrodes made the sensors capable of also detecting light-induced heating.Finally,we present devices on flexible substrates and show that they can be used to detect human touch.
基金support from the Swedish Research Council(VR,2020-00287,2022-00211,2022-06214,2019-04424)the Knut and Alice Wallenberg Foundation,Linköping University and industry through the Wallenberg Wood Science Center+3 种基金the European Research Council(Consolidator grant,101086683)the Swedish Foundation for International Cooperation in Research and Higher Education(STINT),and the Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linköping University(Faculty Grant SFO-Mat-LiU No.200900971)A.R.acknowledges support from the Marie Sklodowska-Curie Actions Seal of Excellent Fellowship program from the Sweden’s Innovation Agency(Vinnova grant 2021-01668)J.E.acknowledges support from the Digital Cellulose Center(Vinnova).M.P.J.and K.T.are Wallenberg Academy Fellows.
文摘Materials that provide dynamically tunable infrared(IR)response are important for many applications,including active camouflage and thermal management.However,current IR-tunable systems often exhibit limitations in mechanical properties or practicality of their tuning modalities,or require complex and costly fabrication methods.An additional challenge relates to providing compatibility between different spectral channels,such as allowing an object to be reversibly concealed in the IR without making it appear in the visible range.Here,we demonstrate that conducting polymer-cellulose papers,fabricated through a simple and cheap approach,can overcome such challenges.The papers exhibit IR properties that can be electrochemically tuned with large modulation(absolute emissivity modulation of 0.4)while maintaining largely constant response in the visible range.Owing to high ionic and electrical conductivity,the tuning of the top surface can be performed electrochemically from the other side of the paper even at tens of micrometer thicknesses,removing the need for overlaying electrode and electrolyte in the optical beam path.These features enabled a series of electrically tunable IR devices,where we focus on demonstrating dynamic radiative coolers,thermal camouflage,anti-counterfeiting tags,and grayscale IR displays.The conducting polymer-cellulose papers are sustainable,cheap,flexible and mechanically robust,providing a versatile materials platformfor active and adaptive IR optoelectronic devices.
