Silver nanowires(Ag NWs)have promising application potential in electronic displays because of their superior flexibility and transparency.Doping Ni in Ag NWs has proven to be an effective strategy to im-prove its wor...Silver nanowires(Ag NWs)have promising application potential in electronic displays because of their superior flexibility and transparency.Doping Ni in Ag NWs has proven to be an effective strategy to im-prove its work function.However,AgNi NWs-based electrodes suffer from poor electrical conductivity under air exposure due to the low-conductivity NiO generated on its surface.Here,Cu was further doped in AgNi NWs to form AgNiCu NWs and regulate its surface oxide under long-term air exposure.Finally,it is demonstrated that the conductivity of AgNiCu NWs can acquire an improved tolerable tempera-ture(over 240℃)and prolonged high-temperature tolerance time(over 150 min)by finely regulating the doping content Cu,indicating an enhanced air-stable conductivity.The optimized AgNiCu NWs also achieve superior transparent conductivity as pure Ag NWs and high work function as AgNi NWs,which has been successfully applied in constructing an n-type photodiode with an effective rectification effect.展开更多
The controlled assembly of nanomaterials has demon-strated significant potential in advancing technological devices.However,achieving highly efficient and low-loss assembly technique for nanomate-rials,enabling the cr...The controlled assembly of nanomaterials has demon-strated significant potential in advancing technological devices.However,achieving highly efficient and low-loss assembly technique for nanomate-rials,enabling the creation of hierarchical structures with distinctive func-tionalities,remains a formidable challenge.Here,we present a method for nanomaterial assembly enhanced by ionic liquids,which enables the fabrication of highly stable,flexible,and transparent electrodes featuring an organized layered structure.The utilization of hydrophobic and non-volatile ionic liquids facilitates the production of stable interfaces with water,effectively preventing the sedimentation of 1D/2D nanomaterials assembled at the interface.Furthermore,the interfacially assembled nanomaterial monolayer exhibits an alternate self-climbing behavior,enabling layer-by-layer transfer and the formation of a well-ordered MXene-wrapped silver nanowire network film.The resulting composite film not only demonstrates exceptional photoelectric performance with a sheet resistance of 9.4Ωsq^(-1) and 93%transmittance,but also showcases remarkable environmental stability and mechanical flexibility.Particularly noteworthy is its application in transparent electromagnetic interference shielding materials and triboelectric nanogenerator devices.This research introduces an innovative approach to manufacture and tailor functional devices based on ordered nanomaterials.展开更多
Monolayer ultra-large graphene oxide （UL-GO） sheets with diameter up to about 100 μm were synthesized based on a chemical method. Transparent conductive films were produced using the UL-GO sheets that were deposite...Monolayer ultra-large graphene oxide （UL-GO） sheets with diameter up to about 100 μm were synthesized based on a chemical method. Transparent conductive films were produced using the UL-GO sheets that were deposited layer-by-layer on a substrate by the Langmuir-Blodgett （L-B） assembly technique. The films produced from UL-GO sheets with a close-packed flat structure exhibit exceptionally high electrical conductivity and transparency after thermal reduction. A remarkable sheet resistance of 605 -/sq at 86% transparency is obtained, which outperforms the graphene films grown on a Ni substrate by chemical vapor deposition. The technique used to produce transparent conductive films is facile, inexpensive and tunable for mass production.展开更多
Flexible and stretchable transparent electrodes are widely used in smart display,energy,wearable devices and other fields.Due to the limitations of flexibility and stretchability of indium tin oxide electrodes,alterna...Flexible and stretchable transparent electrodes are widely used in smart display,energy,wearable devices and other fields.Due to the limitations of flexibility and stretchability of indium tin oxide electrodes,alternative electrodes have appeared,such as metal films,metal nanowires,and conductive meshes.However,few of the above electrodes can simultaneously have excellent flexibility,stretchability,and optoelectronic properties.Nanofiber(NF),a continuous ultra-long one-dimensional conductive material,is considered to be one of the ideal materials for high-performance transparent electrodes with excellent properties due to its unique structure.This paper summarizes the important research progress of NF flexible transparent electrodes(FTEs)in recent years from the aspects of NF electrode materials,preparation technology and application.First,the unique advantages and limitations of various NF materials are systematically discussed.Then,we summarize the preparation technology of various advanced NF FTEs,and point out the future development trend.We also discuss the application of NFs in solar cells,supercapacitors,electric heating equipments,sensors,etc,and analyze its development potential in flexible electronic equipment,as well as problems that need to be solved.Finally,the challenges and future development trends are proposed in the wide application of NF FTEs in the field of flexible optoelectronics.展开更多
Copper nanowires(Cu NWs)are considered an excellent alternative to indium tin oxide(ITO)in flexible transparency electrodes(FTEs).However,the mixed particles and surface oxidation of Cu NWs degrade the transmittance a...Copper nanowires(Cu NWs)are considered an excellent alternative to indium tin oxide(ITO)in flexible transparency electrodes(FTEs).However,the mixed particles and surface oxidation of Cu NWs degrade the transmittance and conductivity of the electrodes.Therefore,highly purified Cu NWs without oxidation are vital for high-performance FTEs.Herein,a facile and effective purification process is introduced to purify Cu NWs in a water and n-hexane system,which takes advantage of the differences in hydrophilicity between Cu NWs and Cu NPs caused by their different adsorption affinities to octadecylamine(ODA).At the same sheet resistance,the transmittance of the purified Cu NW-based FTEs improved approximately 2%compared to that of non-purified Cu NW-based FTEs.Immersion of the electrode in glacial acetic acid removed the surface organics and oxides.After only 40 s of treatment,the sheet resistance dramatically decreased from 10^5 Ohm/sq to 31 Ohm/sq with a transmittance of 85%.In addition,the Cu NW-based FTE conductors showed excellent flexibility(remaining stable after 1000 bending cycles).The Cu NW-based FTEs were further applied to fabricate a flexible transparent heater.At a voltage of 10 V,the temperature of the heater reached 73℃,demonstrating the potential applications of this material in various fields.展开更多
A novel device, lateral PIN photodiode gated by transparent electrode （LPIN PD-GTE） fabricated on fully-depleted SOI film was proposed. ITO film was adopted in the device as gate electrode to reduce the light absorp...A novel device, lateral PIN photodiode gated by transparent electrode （LPIN PD-GTE） fabricated on fully-depleted SOI film was proposed. ITO film was adopted in the device as gate electrode to reduce the light absorption. Thin Si film was fully depleted under gate voltage to achieve low dark current and high photo4o-dark current ratio. The model of gate voltage was obtained and the numerical simulations were presented by ATLAS. Current-voltage characteristics of LPIN PD-GTE obtained in dark （dark current） and under 570 nm illumination （photo current） were studied to achieve the greatest photo-to-dark current ratio for active channel length from 2 to 12 /am. The results show that the photo-to-dark current ratio is 2.0×10^7, with dark current of around 5×10^-4 pA under VGK=0.6 V, PrN=5 mW/cm2, for a total area of 10μm×10μm in fully depleted SOI technology. Thus, the LPIN PD-GTE can be suitable for high-grade photoelectric systems such as blue DVD.展开更多
Flexible electrochromic energy storage devices(FECESDs)for powering flexible electronics have attracted considerable attention.Silver nanowires(AgNWs)are one kind of the most promising flexible transparent electrodes(...Flexible electrochromic energy storage devices(FECESDs)for powering flexible electronics have attracted considerable attention.Silver nanowires(AgNWs)are one kind of the most promising flexible transparent electrodes(FTEs)materials for the emerging flexible devices.Currently,fabricating FECESD based on AgNWs FTEs is still hindered by their intrinsic poor electrochemical stability.To address this issue,a hybrid AgNWs/Co(OH)_(2)/PEDOT:PSS electrode is proposed.The PEDOT:PSS could not only improve the resistance against electrochemical corrosion of AgNWs,but also work as functional layer to realize the color-changing and energy storage properties.Moreover,the Co(OH)_(2)interlayer further improved the color-changing and energy storage performance.Based on the improvement,we assembled the symmetrical FECESDs.Under the same condition,the areal capacitance(0.8 mF cm^(−2))and coloration efficiency(269.80 cm^(2)C−1)of AgNWs/Co(OH)_(2)/PEDOT:PSS FECESDs were obviously higher than AgNWs/PEDOT:PSS FECESDs.Furthermore,the obtained FECESDs exhibited excellent stability against the mechanical deformation.The areal capacitance remained stable during 1000 times cyclic bending with a 25 mm curvature radius.These results demonstrated the broad application potential of the AgNWs/Co(OH)_(2)/PEDOT:PSS FECESD for the emerging portable and multifunctional electronics.展开更多
Ga doped ZnO （OZO）/Cu grid/GZO transparent conductive electrode （TCE） structures were fabricated at room temperature （RT） by using electron beam evaporation （EBE） for the Cu grids and RF magnetron sputtering f...Ga doped ZnO （OZO）/Cu grid/GZO transparent conductive electrode （TCE） structures were fabricated at room temperature （RT） by using electron beam evaporation （EBE） for the Cu grids and RF magnetron sputtering for the GZO layers. In this work, we investigated the electrical and optical characteristics of GZO/Cu grid/GZO multilayer electrode for thin film solar cells by using evaporated Cu grid and sputtered GZO thin films to enhance the optical transparency without significantly affecting their conductivity. The optical transmittance and sheet resistance of GZO/Cu grid/GZO multilayer are higher than those of GZO/Cu film/GZO multilayer independent of Cu grid separation distance and increase with increasing Cu grid separation distances. The calculation of both transmittance and sheet resistance of GZO/Cu grid] GZO multilayer was based on Cu filling factor correlated with the geometry of Cu grid. The calculated values for the transmittance and sheet resistance of the GZO/Cu grid/GZO multilayer were similar to the experimentally observed ones. The highest figure of merit ФTc is 5.18× 10^-3Ω^-1 for the GZO/Cu grid] GZO multilayer with Cu grid separation distance of 1 mm was obtained, in this case, the transmittance and resistivity were 82.72% and 2.17 × 10 ^-4Ωcm, respectively. The transmittance and resistivity are accentahle for nractical thin film snlar cell annlicatinn~展开更多
The electrooxidation behavior of 3, 3′,5, 5′-tetramethylbenzidine(TMB) was investigated using a platinum minigrid optically transparent thin-layer spectroelectrochemical cell. TMB underwent one two-electron electroo...The electrooxidation behavior of 3, 3′,5, 5′-tetramethylbenzidine(TMB) was investigated using a platinum minigrid optically transparent thin-layer spectroelectrochemical cell. TMB underwent one two-electron electrooxidation process to yield quinonediimine in the pH range from 2.0 to < 4.0, and two consecutive one-electron electrooxidation processes, gave the mediate product free radical of TMB first, then gave the oxidation product quinonediimine in the pH range from 4.0 to < 7.0. In the pH range from 7.0 to 10.0, the electrooxidation of TMB was also one two-electron electrooxidation process to yield an azo compound. The formal potential E0'and the electron transfer number of the electrooxidation of TMB at pH 2.0 and pH 8.4 were determined by spectroelectrochemical techniques.展开更多
Chemical vapor deposition(CVD)-gown graphene has tremendous potential as a transparent electrode for the next generation of flexible optoelectronics such as organic light-emitting diodes(OLEDs).A semiconductor coating...Chemical vapor deposition(CVD)-gown graphene has tremendous potential as a transparent electrode for the next generation of flexible optoelectronics such as organic light-emitting diodes(OLEDs).A semiconductor coating is critical to improve the work function but usually makes graphene rougher and more conductive,which increases leakage,and then significantly restrict device effi-ciency improvement and worsens reliability.Here an insulating polyimide bearing carbazole-substituted triphenylamine units and bis(trifluoromethyl)phenyl groups(CzTPA PI/2CF_(3))with high thermal stability is synthesized to passivate graphene.The similar surface free energy allows the uniform coating of CzTPA PI/2CF_(3)/N-methylpyrrolidone on graphene.Despite of a slight decrease in conductivity,CzTPA PI/2CF_(3)passivation enables a substantial reduction in surface roughness and improvement in work function.By using such CzTPA PI/2CF_(3)-passivated graphene as anode,a flexible green OLED is demonstrated with a maximum current,power,and external quantum efficien-cies of 88.4 cd A^(-1),115.7 lm W^(-1),and 24.8%,respectively,which are among the best of the reported results.Moreover,the CzTPA PI/2CF_(3)passivation enhances the device reliability with extending half-life and reducing dispersion coefficient of efficiency.The study promotes the practical use of graphene transparent electrodes for flexible optoelectronics.展开更多
Flexible transparent electrodes(FTEs)have attracted much attention due to their advantages of excellent optical/electrical conductivities and good mechanical fatigue strength.However,their fabrication presents several...Flexible transparent electrodes(FTEs)have attracted much attention due to their advantages of excellent optical/electrical conductivities and good mechanical fatigue strength.However,their fabrication presents several challenges,including fabricating wires with a high aspect ratio and sufficient tensile resistance.In this study,an embedded Ag/Cu metal-mesh FTE with a high figure of merit 24,708(sheet resistance 0.08Ω/sq and 83.4%optical transmittance)is fabricated through the proposed method called self-confined electrohydrodynamic printing and selective electroplating of Cu.This method employs structured surfaces and patterned hydrophilic/hydrophobic properties to enable highly controllable deposition of solutions(e.g.,positioning,line width,consistency),allowing the complete filling of imprinted microgrooves with a high aspect ratio of 2(e.g.,4μm width and 8μm depth)with Ag/Cu metal.Moreover,the resulting FTEs demonstrate good resistance stability under repetitive bending and stretching and exhibit excellent performance in flexible transparent heaters and electromagnetic shielding films.展开更多
Silver nanowires （AgNWs） surrounded by insulating poly（vinylpyrrolidone） have been synthesized by a polyol process and employed as transparent electrodes. The AgNW transparent electrodes can be fabricated by heatt...Silver nanowires （AgNWs） surrounded by insulating poly（vinylpyrrolidone） have been synthesized by a polyol process and employed as transparent electrodes. The AgNW transparent electrodes can be fabricated by heattreatment at about 200 ℃ which forms connecting junctions between AgNWs. Such a heating process is, however, one of the drawbacks of the fabrication of AgNW electrodes on heat-sensitive substrates. Here it has been demonstrated that the electrical conductivity of AgNW electrodes can be improved by mechanical pressing at 25 MPa for 5 s at room temperature. This simple process results in a low sheet resistance of 8.6 Ω/square and a transparency of 80.0%, equivalent to the properties of the AgNW electrodes heated at 200 ℃. This technique makes it possible to fabricate AgNW transparent electrodes on heat-sensitive substrates. The AgNW electrodes on poly（ethylene terephthalate） films exhibited high stability of their electrical conductivities against the repeated bending test. In addition, the surface roughness of the pressed AgNW electrodes is one-third of that of the heat-treated electrode because the AgNW junctions are mechanically compressed. As a result, an organic solar cell fabricated on the pressed AgNW electrodes exhibited a power conversion as much as those fabricated on indium tin oxide electrodes. These findings enable continuous roll-to-roll processing at room temperature, resulting in relatively simple, inexpensive, and scalable processing that is suitable for forthcoming technologies such as organic solar cells, flexible displays, and touch screens.展开更多
We demonstrate the hydrothermal synthesis of long copper nanowires based on a simple protocol. We show that the purification of the nanowires is very important and can be achieved easily by wet treatment with glacial ...We demonstrate the hydrothermal synthesis of long copper nanowires based on a simple protocol. We show that the purification of the nanowires is very important and can be achieved easily by wet treatment with glacial acetic acid. Fabrication of random networks of purified copper nanowires leads to flexible transparent electrodes with excellent optoelectronic performances （e.g., 55 Ω/sq. at 94% transparency）. The process is carried out at room temperature and no post-treatment is necessary. Hybrid materials with the conductive polymer PEDOT：PSS show similar properties （e.g., 46 Ω/sq, at 93% transparency）, with improved mechanical properties. Both electrodes were integrated in capacitive touch sensors.展开更多
Transparent electrodes made of silver nanowires （AgNWs） exhibit higher flexibility when compared to those made of tin doped indium oxide （ITO） and are expected to be applied in plastic electronics. However, these ...Transparent electrodes made of silver nanowires （AgNWs） exhibit higher flexibility when compared to those made of tin doped indium oxide （ITO） and are expected to be applied in plastic electronics. However, these transparent electrodes composed of AgNWs show high haze because the wires cause strong light scattering in the visible range. Reduction of the wire diameter has been proposed as a way to weaken light scattering, although there have seldom been any studies focusing on the haze because of the difficulty involved in controlling the wire diameter. In this report, we show that the haze can be easily reduced by increasing the length of AgNWs with a large diameter. Ultra-long （u-long） AgNWs with lengths in the range of 20-100 μm and a maximum length of 230 μm have been successfully synthesized by adjusting the reaction temperature and the stirring speed of a one-step polyol process. Compared to typical AgNWs （with diameter and length of 70 nm and 10 μm, respectively） and ITO, a transparent electrode consisting of u-long AgNWs 91 nm in diameter demonstrated a low haze of 3.4%-1.6% and a low sheet resistance of 24-109 Ω/sq. at a transmittance of 94%-97%. Even when fabricated at room temperature without any post-treatment, the electrodes composed of u-long AgNWs achieved a sheet resistance of 19 Ω/sq, at a transmittance of 80%, which is six orders of magnitude lower than that of typical AgNWs.展开更多
Copper nanowires （Cu NWs） have attracted increasing attention as building blocks for electronics due to their outstanding electrical properties and low cost. However, organic residues and oxide layers ubiquitously e...Copper nanowires （Cu NWs） have attracted increasing attention as building blocks for electronics due to their outstanding electrical properties and low cost. However, organic residues and oxide layers ubiquitously existing on the surface of Cu NWs impede good inter-wire contact. Commonly used methods such as thermal annealing and acid treatment often lead to nanowire damage. Herein, hydrogen plasma treatment at room temperature has been demonstrated to be effective for simultaneous surface cleaning and selective welding of Cu NWs at junctions. Transparent electrodes with excellent optical-electrical performance （19 ff）-sq-1 @ 90% T） and enhanced stability have been fabricated and integrated into organic solar cells. Besides, Cu NW conductors with superior stretchability and cycling stability under stretching speeds of up to 400 mm-min-＇ can also be produced by the nanowelding process, and the feasibility of their application in stretchable LED circuits has been demonstrated.展开更多
Transparent, flexible electronic skin holds a wide range of applications in robotics, humanmachine interfaces, artificial intelligence, prosthetics, and health monitoring. Silver nanowire are mechanically flexible and...Transparent, flexible electronic skin holds a wide range of applications in robotics, humanmachine interfaces, artificial intelligence, prosthetics, and health monitoring. Silver nanowire are mechanically flexible and robust, which exhibit great potential in transparent and electricconducting thin film. Herein, we report on a silver-nanowire spray-coating and electrodemicrostructure replicating strategy to construct a transparent, flexible, and sensitive electronic skin device. The electronic skin device shows highly sensitive piezo-capacitance response to pressure. It is found that micropatterning the surface of dielectric layer polyurethane elastomer by replicating from microstructures of natural-existing surfaces such as lotus leaf, silk, and frosted glass can greatly enhance the piezo-capacitance performance of the device. The microstructured pressure sensors based on silver nanowire exhibit good transparency, excellent flexibility, wide pressure detection range （0-150 kPa）, and high sensitivity （1.28 kPa-1）.展开更多
The thermal decomposition synthesis of long copper nanowires （CuNWs） was achieved by controlling the synthesis parameters. A detailed study was performed to determine the effect of the molar ratio of copper chloride...The thermal decomposition synthesis of long copper nanowires （CuNWs） was achieved by controlling the synthesis parameters. A detailed study was performed to determine the effect of the molar ratio of copper chloride to nickel acetylacetonate, temperature, and stirring rate on the final shape of the products. Transparent electrodes （TEs） were fabricated by wet treatment with acetic acid （AA）, without using a sintering process. The low oxidation stability and high surface roughness are the main disadvantages of the CuNW TEs, which limit their applications. In order to overcome these issues, we prepared CuNW/polymer composite TEs by partial embedding of the CuNWs into poly（methyl methacrylate） （PMMA） on poly（ethylene terephthalate） （PET） substrates. The CuNW/PMMA composite TEs exhibit excellent optoelectronic performance （91.3% at 100.7 ff2/sq）, low surface roughness （4.6 nm in height）, and good mechanical and chemical stability as compared with CuNW TEs. On the basis of these properties, we believe that CuNW-based composite TEs could serve as low-cost materials for a wide range of new optoelectronic devices.展开更多
Graphene oxide and silver nanowires were bar coated onto polyethylene terephthalate （PET） substrates and then welded using an ultraviolet （UV）-assisted flash light irradiation process to achieve both high electric...Graphene oxide and silver nanowires were bar coated onto polyethylene terephthalate （PET） substrates and then welded using an ultraviolet （UV）-assisted flash light irradiation process to achieve both high electrical conductivity and low haze. The irradiation process connected adjacent silver nanowires by welding, while simultaneously reducing the graphene oxide to graphene. This process was performed using a custom W-assisted flash light welding system at room temperature under ambient conditions and was extremely rapid, with processing time of several milliseconds. The effects of varying the weight fractions of the silver nanowires and graphene oxide and of varying the W-assisted flash light welding conditions （light energy and pulse duration） were investigated. The surface morphologies of the welded silver nanowire/graphene films were analyzed using scanning electron microscopy. Optical characterizations, including transmittance and haze measurements, were also conducted using a spectrophotometer. To test their resistance to oxidation, the welded silver nanowire/graphene films were subjected to high temperature in a furnace （100 ℃）, and their sheet resistances were measured every hour. The flash light welding process was found to yield silver nanowire/graphene films with high oxidation resistance, high conductivity （14.35 Ω·sq-1）, high transmittance （93.46%）, and low haze （0.9%）. This material showed uniform temperature distribution when applied as a resistive heating film.展开更多
Graphene mesh electrodes （GMEs） with good conductivity and transparency have been fabricated by the standard industrial photolithography and 02 plasma etching process using graphene solutions. Organic photovoltaic ...Graphene mesh electrodes （GMEs） with good conductivity and transparency have been fabricated by the standard industrial photolithography and 02 plasma etching process using graphene solutions. Organic photovoltaic （OPV） cells using GMEs as the transparent electrodes with a blend of poly-（3-hexylthiophene） phenyl-C61-butyric acid methyl ester （P3HT/PC61BM） as the active layer have been fabricated and exhibit a power conversion efficiency （PCE） of 2.04%, the highest PCE for solution-processed graphene transparent electrode-based solar cells reported to date.展开更多
Flexible transparent electrodes(FTEs) with robust mechanical stability are crucial for the industrial application of flexible organic solar cells(OSCs). However, their production remains challenging owing to the diffi...Flexible transparent electrodes(FTEs) with robust mechanical stability are crucial for the industrial application of flexible organic solar cells(OSCs). However, their production remains challenging owing to the difficulty in balancing the conductivity,transmittance, and adhesion of FTEs to substrates. Herein, we present the so-called “reinforced concrete” strategy which finetunes the structure of silver nanowires(Ag NWs)-based FTEs with polydopamine(PDA) possessing good adhesion properties and moderate reducibility. The PDA reduces Ag+to form silver nanoparticles(Ag NPs) which grow like “rivets” at the Ag NW junction sites;PDA stabilizes the Ag NW skeleton and improves the adhesion between the Ag NWs and polyethylene terephthalate(PET) substrate and interface layer. The obtained Ag NW:PDA:Ag NP FTE exhibits excellent optoelectronic properties and high mechanical stability. The resulting flexible OSCs exhibit 17.07% efficiency, high flexibility during 10,000 bending test cycles, and robust peeling stability. In addition, this “reinforced concrete”-like FTE provides great advantages for the production of large-area flexible OSCs, thereby paving a new way toward their commercial application.展开更多
基金supported by the National Natural Science Foundation of China(Nos.62374035,92263106,12061131009)the Science and Technology Commission of Shanghai Municipality(No.21520712600).
文摘Silver nanowires(Ag NWs)have promising application potential in electronic displays because of their superior flexibility and transparency.Doping Ni in Ag NWs has proven to be an effective strategy to im-prove its work function.However,AgNi NWs-based electrodes suffer from poor electrical conductivity under air exposure due to the low-conductivity NiO generated on its surface.Here,Cu was further doped in AgNi NWs to form AgNiCu NWs and regulate its surface oxide under long-term air exposure.Finally,it is demonstrated that the conductivity of AgNiCu NWs can acquire an improved tolerable tempera-ture(over 240℃)and prolonged high-temperature tolerance time(over 150 min)by finely regulating the doping content Cu,indicating an enhanced air-stable conductivity.The optimized AgNiCu NWs also achieve superior transparent conductivity as pure Ag NWs and high work function as AgNi NWs,which has been successfully applied in constructing an n-type photodiode with an effective rectification effect.
基金This work was supported by the National Natural Science Foundation of China(nos.21988102,and 22305026)the China Postdoctoral Science Foundation(2019M650433).
文摘The controlled assembly of nanomaterials has demon-strated significant potential in advancing technological devices.However,achieving highly efficient and low-loss assembly technique for nanomate-rials,enabling the creation of hierarchical structures with distinctive func-tionalities,remains a formidable challenge.Here,we present a method for nanomaterial assembly enhanced by ionic liquids,which enables the fabrication of highly stable,flexible,and transparent electrodes featuring an organized layered structure.The utilization of hydrophobic and non-volatile ionic liquids facilitates the production of stable interfaces with water,effectively preventing the sedimentation of 1D/2D nanomaterials assembled at the interface.Furthermore,the interfacially assembled nanomaterial monolayer exhibits an alternate self-climbing behavior,enabling layer-by-layer transfer and the formation of a well-ordered MXene-wrapped silver nanowire network film.The resulting composite film not only demonstrates exceptional photoelectric performance with a sheet resistance of 9.4Ωsq^(-1) and 93%transmittance,but also showcases remarkable environmental stability and mechanical flexibility.Particularly noteworthy is its application in transparent electromagnetic interference shielding materials and triboelectric nanogenerator devices.This research introduces an innovative approach to manufacture and tailor functional devices based on ordered nanomaterials.
基金Project (51102170) supported by the National Natural Science Foundation of ChinaProject (2010CB234609) supported by the National Basic Research Program of China
文摘Monolayer ultra-large graphene oxide （UL-GO） sheets with diameter up to about 100 μm were synthesized based on a chemical method. Transparent conductive films were produced using the UL-GO sheets that were deposited layer-by-layer on a substrate by the Langmuir-Blodgett （L-B） assembly technique. The films produced from UL-GO sheets with a close-packed flat structure exhibit exceptionally high electrical conductivity and transparency after thermal reduction. A remarkable sheet resistance of 605 -/sq at 86% transparency is obtained, which outperforms the graphene films grown on a Ni substrate by chemical vapor deposition. The technique used to produce transparent conductive films is facile, inexpensive and tunable for mass production.
基金supported by the National Natural Science Foundation of China(Grant No.52175331)the Support plan for Outstanding Youth Innovation Team in Universities of Shandong Province,China(Grand No.2020KJB003)Natural Science Foundation of Shandong Province,China(Granted Nos.ZR2022ME014,ZR2021ME139 and ZR2020ZD04)。
文摘Flexible and stretchable transparent electrodes are widely used in smart display,energy,wearable devices and other fields.Due to the limitations of flexibility and stretchability of indium tin oxide electrodes,alternative electrodes have appeared,such as metal films,metal nanowires,and conductive meshes.However,few of the above electrodes can simultaneously have excellent flexibility,stretchability,and optoelectronic properties.Nanofiber(NF),a continuous ultra-long one-dimensional conductive material,is considered to be one of the ideal materials for high-performance transparent electrodes with excellent properties due to its unique structure.This paper summarizes the important research progress of NF flexible transparent electrodes(FTEs)in recent years from the aspects of NF electrode materials,preparation technology and application.First,the unique advantages and limitations of various NF materials are systematically discussed.Then,we summarize the preparation technology of various advanced NF FTEs,and point out the future development trend.We also discuss the application of NFs in solar cells,supercapacitors,electric heating equipments,sensors,etc,and analyze its development potential in flexible electronic equipment,as well as problems that need to be solved.Finally,the challenges and future development trends are proposed in the wide application of NF FTEs in the field of flexible optoelectronics.
基金the National Natural Science Foundation of China(Grant No.51522503)the Program for New Century Excellent Talents in University(NCET-13-0175).
文摘Copper nanowires(Cu NWs)are considered an excellent alternative to indium tin oxide(ITO)in flexible transparency electrodes(FTEs).However,the mixed particles and surface oxidation of Cu NWs degrade the transmittance and conductivity of the electrodes.Therefore,highly purified Cu NWs without oxidation are vital for high-performance FTEs.Herein,a facile and effective purification process is introduced to purify Cu NWs in a water and n-hexane system,which takes advantage of the differences in hydrophilicity between Cu NWs and Cu NPs caused by their different adsorption affinities to octadecylamine(ODA).At the same sheet resistance,the transmittance of the purified Cu NW-based FTEs improved approximately 2%compared to that of non-purified Cu NW-based FTEs.Immersion of the electrode in glacial acetic acid removed the surface organics and oxides.After only 40 s of treatment,the sheet resistance dramatically decreased from 10^5 Ohm/sq to 31 Ohm/sq with a transmittance of 85%.In addition,the Cu NW-based FTE conductors showed excellent flexibility(remaining stable after 1000 bending cycles).The Cu NW-based FTEs were further applied to fabricate a flexible transparent heater.At a voltage of 10 V,the temperature of the heater reached 73℃,demonstrating the potential applications of this material in various fields.
基金Project(61040061) supported by the National Natural Science Foundation of ChinaProject supported by Hunan Provincial Innovation Foundation for Postgraduate Students,China
文摘A novel device, lateral PIN photodiode gated by transparent electrode （LPIN PD-GTE） fabricated on fully-depleted SOI film was proposed. ITO film was adopted in the device as gate electrode to reduce the light absorption. Thin Si film was fully depleted under gate voltage to achieve low dark current and high photo4o-dark current ratio. The model of gate voltage was obtained and the numerical simulations were presented by ATLAS. Current-voltage characteristics of LPIN PD-GTE obtained in dark （dark current） and under 570 nm illumination （photo current） were studied to achieve the greatest photo-to-dark current ratio for active channel length from 2 to 12 /am. The results show that the photo-to-dark current ratio is 2.0×10^7, with dark current of around 5×10^-4 pA under VGK=0.6 V, PrN=5 mW/cm2, for a total area of 10μm×10μm in fully depleted SOI technology. Thus, the LPIN PD-GTE can be suitable for high-grade photoelectric systems such as blue DVD.
基金supports from the National Natural Science Foundation of China (Grant No. 52175300)Fundamental Research Funds for the Central Universities (2022FRFK060008)+2 种基金Heilongjiang Touyan Innovation Team Program (HITTY-20190013)Shenzhen Fundamental Research Programs (JCYJ20200925160843002)Start-up fund of SUSTech (Y01256114)
文摘Flexible electrochromic energy storage devices(FECESDs)for powering flexible electronics have attracted considerable attention.Silver nanowires(AgNWs)are one kind of the most promising flexible transparent electrodes(FTEs)materials for the emerging flexible devices.Currently,fabricating FECESD based on AgNWs FTEs is still hindered by their intrinsic poor electrochemical stability.To address this issue,a hybrid AgNWs/Co(OH)_(2)/PEDOT:PSS electrode is proposed.The PEDOT:PSS could not only improve the resistance against electrochemical corrosion of AgNWs,but also work as functional layer to realize the color-changing and energy storage properties.Moreover,the Co(OH)_(2)interlayer further improved the color-changing and energy storage performance.Based on the improvement,we assembled the symmetrical FECESDs.Under the same condition,the areal capacitance(0.8 mF cm^(−2))and coloration efficiency(269.80 cm^(2)C−1)of AgNWs/Co(OH)_(2)/PEDOT:PSS FECESDs were obviously higher than AgNWs/PEDOT:PSS FECESDs.Furthermore,the obtained FECESDs exhibited excellent stability against the mechanical deformation.The areal capacitance remained stable during 1000 times cyclic bending with a 25 mm curvature radius.These results demonstrated the broad application potential of the AgNWs/Co(OH)_(2)/PEDOT:PSS FECESD for the emerging portable and multifunctional electronics.
基金support of the key project of the National Natural Science Foundation of China under Grant Nos.91333203 and 51172204the Program for Innovative Research Team in University of Ministry of Education of China under Grant No.IRT13037the Zhejiang Provincial Department of Science and Technology of China under Grant No.2010R50020
文摘Ga doped ZnO （OZO）/Cu grid/GZO transparent conductive electrode （TCE） structures were fabricated at room temperature （RT） by using electron beam evaporation （EBE） for the Cu grids and RF magnetron sputtering for the GZO layers. In this work, we investigated the electrical and optical characteristics of GZO/Cu grid/GZO multilayer electrode for thin film solar cells by using evaporated Cu grid and sputtered GZO thin films to enhance the optical transparency without significantly affecting their conductivity. The optical transmittance and sheet resistance of GZO/Cu grid/GZO multilayer are higher than those of GZO/Cu film/GZO multilayer independent of Cu grid separation distance and increase with increasing Cu grid separation distances. The calculation of both transmittance and sheet resistance of GZO/Cu grid] GZO multilayer was based on Cu filling factor correlated with the geometry of Cu grid. The calculated values for the transmittance and sheet resistance of the GZO/Cu grid/GZO multilayer were similar to the experimentally observed ones. The highest figure of merit ФTc is 5.18× 10^-3Ω^-1 for the GZO/Cu grid] GZO multilayer with Cu grid separation distance of 1 mm was obtained, in this case, the transmittance and resistivity were 82.72% and 2.17 × 10 ^-4Ωcm, respectively. The transmittance and resistivity are accentahle for nractical thin film snlar cell annlicatinn~
基金The project was supported by the National Natural Science Foundation of China(Grant No.20075013).
文摘The electrooxidation behavior of 3, 3′,5, 5′-tetramethylbenzidine(TMB) was investigated using a platinum minigrid optically transparent thin-layer spectroelectrochemical cell. TMB underwent one two-electron electrooxidation process to yield quinonediimine in the pH range from 2.0 to < 4.0, and two consecutive one-electron electrooxidation processes, gave the mediate product free radical of TMB first, then gave the oxidation product quinonediimine in the pH range from 4.0 to < 7.0. In the pH range from 7.0 to 10.0, the electrooxidation of TMB was also one two-electron electrooxidation process to yield an azo compound. The formal potential E0'and the electron transfer number of the electrooxidation of TMB at pH 2.0 and pH 8.4 were determined by spectroelectrochemical techniques.
基金Ministry of Science and Technology of China,Grant/Award Number:2021YFA1200804National Science Foundation of China,Grant/Award Numbers:52172057,52188101,52002375+4 种基金Chinese Academy of Sciences,Grant/Award Numbers:ZDBS-LY-JSC027,XDB30000000Postdoctoral Science Foundation of China,Grant/Award Numbers:2020TQ0328,2023M743569Special Projects of the Central Government in Guidance of Local Science and Technology Development,Grant/Award Number:2024010859-JH6/1006IMR Innovation Fund,Grant/Award Number:2023-PY17Guangdong Basic and Applied Basic Research Foundation,Grant/Award Number:2020B0301030002。
文摘Chemical vapor deposition(CVD)-gown graphene has tremendous potential as a transparent electrode for the next generation of flexible optoelectronics such as organic light-emitting diodes(OLEDs).A semiconductor coating is critical to improve the work function but usually makes graphene rougher and more conductive,which increases leakage,and then significantly restrict device effi-ciency improvement and worsens reliability.Here an insulating polyimide bearing carbazole-substituted triphenylamine units and bis(trifluoromethyl)phenyl groups(CzTPA PI/2CF_(3))with high thermal stability is synthesized to passivate graphene.The similar surface free energy allows the uniform coating of CzTPA PI/2CF_(3)/N-methylpyrrolidone on graphene.Despite of a slight decrease in conductivity,CzTPA PI/2CF_(3)passivation enables a substantial reduction in surface roughness and improvement in work function.By using such CzTPA PI/2CF_(3)-passivated graphene as anode,a flexible green OLED is demonstrated with a maximum current,power,and external quantum efficien-cies of 88.4 cd A^(-1),115.7 lm W^(-1),and 24.8%,respectively,which are among the best of the reported results.Moreover,the CzTPA PI/2CF_(3)passivation enhances the device reliability with extending half-life and reducing dispersion coefficient of efficiency.The study promotes the practical use of graphene transparent electrodes for flexible optoelectronics.
基金supported by the National Key Research and Development Program of China(2021YFB3200700)the National Natural Science Foundation of China(51925503,52175537).
文摘Flexible transparent electrodes(FTEs)have attracted much attention due to their advantages of excellent optical/electrical conductivities and good mechanical fatigue strength.However,their fabrication presents several challenges,including fabricating wires with a high aspect ratio and sufficient tensile resistance.In this study,an embedded Ag/Cu metal-mesh FTE with a high figure of merit 24,708(sheet resistance 0.08Ω/sq and 83.4%optical transmittance)is fabricated through the proposed method called self-confined electrohydrodynamic printing and selective electroplating of Cu.This method employs structured surfaces and patterned hydrophilic/hydrophobic properties to enable highly controllable deposition of solutions(e.g.,positioning,line width,consistency),allowing the complete filling of imprinted microgrooves with a high aspect ratio of 2(e.g.,4μm width and 8μm depth)with Ag/Cu metal.Moreover,the resulting FTEs demonstrate good resistance stability under repetitive bending and stretching and exhibit excellent performance in flexible transparent heaters and electromagnetic shielding films.
文摘Silver nanowires （AgNWs） surrounded by insulating poly（vinylpyrrolidone） have been synthesized by a polyol process and employed as transparent electrodes. The AgNW transparent electrodes can be fabricated by heattreatment at about 200 ℃ which forms connecting junctions between AgNWs. Such a heating process is, however, one of the drawbacks of the fabrication of AgNW electrodes on heat-sensitive substrates. Here it has been demonstrated that the electrical conductivity of AgNW electrodes can be improved by mechanical pressing at 25 MPa for 5 s at room temperature. This simple process results in a low sheet resistance of 8.6 Ω/square and a transparency of 80.0%, equivalent to the properties of the AgNW electrodes heated at 200 ℃. This technique makes it possible to fabricate AgNW transparent electrodes on heat-sensitive substrates. The AgNW electrodes on poly（ethylene terephthalate） films exhibited high stability of their electrical conductivities against the repeated bending test. In addition, the surface roughness of the pressed AgNW electrodes is one-third of that of the heat-treated electrode because the AgNW junctions are mechanically compressed. As a result, an organic solar cell fabricated on the pressed AgNW electrodes exhibited a power conversion as much as those fabricated on indium tin oxide electrodes. These findings enable continuous roll-to-roll processing at room temperature, resulting in relatively simple, inexpensive, and scalable processing that is suitable for forthcoming technologies such as organic solar cells, flexible displays, and touch screens.
文摘We demonstrate the hydrothermal synthesis of long copper nanowires based on a simple protocol. We show that the purification of the nanowires is very important and can be achieved easily by wet treatment with glacial acetic acid. Fabrication of random networks of purified copper nanowires leads to flexible transparent electrodes with excellent optoelectronic performances （e.g., 55 Ω/sq. at 94% transparency）. The process is carried out at room temperature and no post-treatment is necessary. Hybrid materials with the conductive polymer PEDOT：PSS show similar properties （e.g., 46 Ω/sq, at 93% transparency）, with improved mechanical properties. Both electrodes were integrated in capacitive touch sensors.
文摘Transparent electrodes made of silver nanowires （AgNWs） exhibit higher flexibility when compared to those made of tin doped indium oxide （ITO） and are expected to be applied in plastic electronics. However, these transparent electrodes composed of AgNWs show high haze because the wires cause strong light scattering in the visible range. Reduction of the wire diameter has been proposed as a way to weaken light scattering, although there have seldom been any studies focusing on the haze because of the difficulty involved in controlling the wire diameter. In this report, we show that the haze can be easily reduced by increasing the length of AgNWs with a large diameter. Ultra-long （u-long） AgNWs with lengths in the range of 20-100 μm and a maximum length of 230 μm have been successfully synthesized by adjusting the reaction temperature and the stirring speed of a one-step polyol process. Compared to typical AgNWs （with diameter and length of 70 nm and 10 μm, respectively） and ITO, a transparent electrode consisting of u-long AgNWs 91 nm in diameter demonstrated a low haze of 3.4%-1.6% and a low sheet resistance of 24-109 Ω/sq. at a transmittance of 94%-97%. Even when fabricated at room temperature without any post-treatment, the electrodes composed of u-long AgNWs achieved a sheet resistance of 19 Ω/sq, at a transmittance of 80%, which is six orders of magnitude lower than that of typical AgNWs.
基金This work was financially supported by the National Basic Research Program of China （No. 2012CB932303）, the National Natural Science Foundation of China （No. 61301036）, Shanghai Municipal Natural Science Foundation （No. 13ZR1463600）, and the Innovation Project of Shanghai Institute of Ceramics.
文摘Copper nanowires （Cu NWs） have attracted increasing attention as building blocks for electronics due to their outstanding electrical properties and low cost. However, organic residues and oxide layers ubiquitously existing on the surface of Cu NWs impede good inter-wire contact. Commonly used methods such as thermal annealing and acid treatment often lead to nanowire damage. Herein, hydrogen plasma treatment at room temperature has been demonstrated to be effective for simultaneous surface cleaning and selective welding of Cu NWs at junctions. Transparent electrodes with excellent optical-electrical performance （19 ff）-sq-1 @ 90% T） and enhanced stability have been fabricated and integrated into organic solar cells. Besides, Cu NW conductors with superior stretchability and cycling stability under stretching speeds of up to 400 mm-min-＇ can also be produced by the nanowelding process, and the feasibility of their application in stretchable LED circuits has been demonstrated.
基金This work was supported by the National Natural Science Foundation of China （No.61674078） and Dongrun- Yau Science Silver Award （Chemistry）.
文摘Transparent, flexible electronic skin holds a wide range of applications in robotics, humanmachine interfaces, artificial intelligence, prosthetics, and health monitoring. Silver nanowire are mechanically flexible and robust, which exhibit great potential in transparent and electricconducting thin film. Herein, we report on a silver-nanowire spray-coating and electrodemicrostructure replicating strategy to construct a transparent, flexible, and sensitive electronic skin device. The electronic skin device shows highly sensitive piezo-capacitance response to pressure. It is found that micropatterning the surface of dielectric layer polyurethane elastomer by replicating from microstructures of natural-existing surfaces such as lotus leaf, silk, and frosted glass can greatly enhance the piezo-capacitance performance of the device. The microstructured pressure sensors based on silver nanowire exhibit good transparency, excellent flexibility, wide pressure detection range （0-150 kPa）, and high sensitivity （1.28 kPa-1）.
文摘The thermal decomposition synthesis of long copper nanowires （CuNWs） was achieved by controlling the synthesis parameters. A detailed study was performed to determine the effect of the molar ratio of copper chloride to nickel acetylacetonate, temperature, and stirring rate on the final shape of the products. Transparent electrodes （TEs） were fabricated by wet treatment with acetic acid （AA）, without using a sintering process. The low oxidation stability and high surface roughness are the main disadvantages of the CuNW TEs, which limit their applications. In order to overcome these issues, we prepared CuNW/polymer composite TEs by partial embedding of the CuNWs into poly（methyl methacrylate） （PMMA） on poly（ethylene terephthalate） （PET） substrates. The CuNW/PMMA composite TEs exhibit excellent optoelectronic performance （91.3% at 100.7 ff2/sq）, low surface roughness （4.6 nm in height）, and good mechanical and chemical stability as compared with CuNW TEs. On the basis of these properties, we believe that CuNW-based composite TEs could serve as low-cost materials for a wide range of new optoelectronic devices.
文摘Graphene oxide and silver nanowires were bar coated onto polyethylene terephthalate （PET） substrates and then welded using an ultraviolet （UV）-assisted flash light irradiation process to achieve both high electrical conductivity and low haze. The irradiation process connected adjacent silver nanowires by welding, while simultaneously reducing the graphene oxide to graphene. This process was performed using a custom W-assisted flash light welding system at room temperature under ambient conditions and was extremely rapid, with processing time of several milliseconds. The effects of varying the weight fractions of the silver nanowires and graphene oxide and of varying the W-assisted flash light welding conditions （light energy and pulse duration） were investigated. The surface morphologies of the welded silver nanowire/graphene films were analyzed using scanning electron microscopy. Optical characterizations, including transmittance and haze measurements, were also conducted using a spectrophotometer. To test their resistance to oxidation, the welded silver nanowire/graphene films were subjected to high temperature in a furnace （100 ℃）, and their sheet resistances were measured every hour. The flash light welding process was found to yield silver nanowire/graphene films with high oxidation resistance, high conductivity （14.35 Ω·sq-1）, high transmittance （93.46%）, and low haze （0.9%）. This material showed uniform temperature distribution when applied as a resistive heating film.
文摘Graphene mesh electrodes （GMEs） with good conductivity and transparency have been fabricated by the standard industrial photolithography and 02 plasma etching process using graphene solutions. Organic photovoltaic （OPV） cells using GMEs as the transparent electrodes with a blend of poly-（3-hexylthiophene） phenyl-C61-butyric acid methyl ester （P3HT/PC61BM） as the active layer have been fabricated and exhibit a power conversion efficiency （PCE） of 2.04%, the highest PCE for solution-processed graphene transparent electrode-based solar cells reported to date.
基金supported by the National Natural Science Foundation of China (51922074, 22075194, 51820105003)the National Key Research and Development Program of China(2020YFB1506400)+3 种基金the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (20KJA430010)the Tang Scholarthe Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)Collaborative Innovation Center of Suzhou Nano Science and Technology。
文摘Flexible transparent electrodes(FTEs) with robust mechanical stability are crucial for the industrial application of flexible organic solar cells(OSCs). However, their production remains challenging owing to the difficulty in balancing the conductivity,transmittance, and adhesion of FTEs to substrates. Herein, we present the so-called “reinforced concrete” strategy which finetunes the structure of silver nanowires(Ag NWs)-based FTEs with polydopamine(PDA) possessing good adhesion properties and moderate reducibility. The PDA reduces Ag+to form silver nanoparticles(Ag NPs) which grow like “rivets” at the Ag NW junction sites;PDA stabilizes the Ag NW skeleton and improves the adhesion between the Ag NWs and polyethylene terephthalate(PET) substrate and interface layer. The obtained Ag NW:PDA:Ag NP FTE exhibits excellent optoelectronic properties and high mechanical stability. The resulting flexible OSCs exhibit 17.07% efficiency, high flexibility during 10,000 bending test cycles, and robust peeling stability. In addition, this “reinforced concrete”-like FTE provides great advantages for the production of large-area flexible OSCs, thereby paving a new way toward their commercial application.
