S-1805/Ag/Au Hybrid Transparent Electrodes for ITO-free Flexible Organic Photovoltaics

We fabricated an S-1805/Ag/Au hybrid transparent electrode based on 4.4 lini ultrathin Au film, which exhibited a high transparency(T=78% at 550 nm), a low sheet resistance(Rs=70Ωl/sq), and an extremely smooth surface(roughness=0.37 nm). The three-dimensional(3D) island growth mode of 4.4 nm Au film was resisted by tlie chemical bonding effect of the nonconductive S-1805 film and the wetting behavior of 0.6 nm Ag layer. The S-1805/Ag/Au hybrid transparent electrodes were used as the replacement of ITO anodes in flexible organic photovoltaics(OPVs), and the S-1805/Ag/Au-based OP Vs resulted in the similar power conversion efficiency compared to ITO-based devices. High flexibility and mechanical robustness were demonstrated in the ITO-free OPVs without obvious degeneration in device performance after over 2000 repeated bending cycles.

Electrohydrodynamic lithography of metallic mesh for optically transparent flexible and conformal antennas

The optically transparent antenna is becoming a very attractive proposition for various applications, such as wearable devices and vehicle radars. The fabrication of transparent flexible/conformal antennas is a long-lasting interest in academia and industry.However, the preparation of radio-frequency radiators with excellent conductivity and optical transmittance is still quite challenging. Herein, we introduce a facile approach to directly fabricate optically transparent flexible and conformal coplanar waveguide-fed antennas using programmable electrohydrodynamic lithography. Metallic meshes with transmittance above 90%have been successfully created based on the conformal electrohydrodynamic printing of high-viscosity photoresist masks, and the corresponding sheet resistance can be tuned down to ~2 Ω/□. Then, the geometrical structure of the proposed transparent antenna has been systematically optimized because of the basic radio frequency components, including the radiator, feeder line,ground plane, and size of metallic meshes. Optically transparent flexible and conformal antennas are finally obtained, presenting an optical transmittance of 92% and 55%, respectively. The simulated and measured results demonstrate that the transparent antennas with a good optoelectronic performance indeed exhibit a nice electromagnetic behavior. We believe that this newly developed conformal electrohydrodynamic lithography method can be utilized to fabricate a variety of other transparent electronic devices, such as transparent electromagnetic shielding meshes on aircraft canopies, in the future.

Understanding of the Relationship between the Properties of Cu(In,Ga)Se_(2) Solar Cells and the Structure of Ag Network Electrodes

The relation between the structure of the silver network electrodes and the properties of Cu(In,Ga)Se_(2)(CIGS)solar cells is systemically investigated.The Ag network electrode is deposited onto an Al:ZnO(AZO)thin film,employing a self-forming cracked template.Precise control over the cracked template's structure is achieved through careful adjustment of temperature and humidity.The Ag network electrodes with different coverage areas and network densities are systemically applied to the CIGS solar cells.It is revealed that predominant fill factor(FF)is influenced by the figure of merit of transparent conducting electrodes,rather than sheet resistance,particularly when the coverage area falls within the range of 1.3–5%.Furthermore,a higher network density corresponds to an enhanced FF when the coverage areas of the Ag networks are similar.When utilizing a thinner AZO film,CIGS solar cells with a surface area of 1.0609 cm^(2)exhibit a notable performance improvement,with efficiency increasing from 10.48%to 11.63%.This enhancement is primarily attributed to the increase in FF from 45%to 65%.These findings underscore the considerable potential for reducing the thickness of the transparent conductive oxide(TCO)in CIGS modules with implications for practical applications in photovoltaic technology.

Fast ion diffusion alloy layer facilitating 3D mesh substrate for dendrite-free zinc-ion hybrid capacitors

Although aqueous zinc ion hybrid capacitors have advantageous integration of batteries and supercapacitors,they still suffer from the inherent problems of dendrite growth and interfacial side reactions on Zn anodes.Herein,a universal fast zinc-ion diffusion layer on a three-dimensional(3 D)mesh structure model is demonstrated to effectively improve Zn plating/stripping reversibility.The fast ion diffusion alloy layer accelerates the Zn^(2+)migration in an orderly manner to homogenize Zn^(2+)flux and overcomes the defects of the commercial mesh substrate,effectively avoiding dendrite growth and side reactions.Consequently,the proof-of-concept silver-zinc alloy modified stainless steel mesh delivers superb reversibility with the high coulombic efficiency over 99.4%at 4 mA cm^(-2)after 1600 cycles and excellent reliability of over 830 h at 1 mA cm^(-2),Its feasibility is also evidenced in commercial zinc ion hybrid capacitors with activated carbon as the cathode.This work enriches the fundamental comprehension of fast zinc-ion diffusion layer combined with a 3 D substrate on the Zn deposition and opens a universal approach to design advanced host for Zn electrodes in zinc ion hybrid capacitors.

金属网格-透明导电氧化物复合型透明电极的瑞利分析和仿真

以氧化铟锡(indium tin oxide,ITO)为代表的透明导电氧化物(transparent conducting oxide,TCO)在当前光电器件中的重要性日益增长.通过在TCO中引入金属网格构成复合电极,可以在保持良好透明性的前提下有效提升电学性能,同时降低对铟的需求量,并为可穿戴设备所需的柔性电极提供可能方案.对此类电极的电学性能分析,如复合电极方阻随金属网格结构参数的变化,可为电极设计与制备提供基本的出发点,但相关理论尚十分缺乏.本文针对典型的方孔方格型金属网格-TCO复合电极,分别展开基于瑞利模型和基于有限元仿真的电学性能分析.结果表明,孔型近似导致的金属通道显著畸变是复合电极的电学计算中瑞利模型在中高开口率下失效的主要原因.据此,我们采用格型修正,通过提升瑞利模型中的原胞外边界对称性来改善金属通道的畸变.与电极仿真的对比表明,修正后瑞利模型的适用范围明显扩大,其结果可与实验数据很好地拟合,为此类复合透明电极的电学数据分析与结构设计提供了简洁高效的理论工具.

基于超快激光定域去除的Cu/Ag复合金属网格透明电极性能优化研究

[目的]Ag网格透明电极方块电阻低,但反射率高。[方法]在钠钙玻璃基底表面利用等离子射频磁控溅射沉积Cu/Ag复合金属薄膜,然后采用飞秒脉冲激光定域去除金属层,获得Cu/Ag复合金属网格透明电极。分析了激光能量密度、激光扫描速率和激光扫描线重叠率对电极材料去除的影响机制。[结果]在激光能量密度1.4 J/cm^(2)、激光扫描速率300 mm/s和激光扫描线重叠率70%的工艺参数下获得了综合光电性能最为出色的Cu/Ag复合金属网格透明电极,其平均透光率为87.58%,方块电阻为2.15Ω,品质因子为1.235×10^(-1)Ω^(-1)。[结论]该电极的综合性能与传统商用ITO(掺锡氧化铟)透明电极相比有巨大提升。

High-efficiency stretchable organic light-emitting diodes based on ultra-flexible printed embedded metal composite electrodes

Stretchable organic light-emitting diodes(OLEDs)are important components for flexible/wearable electronics.However,the efficiency of the existing stretchable OLEDs is still much lower as compared with their rigid counterparts,one of the main reasons being the lack of ideal flexible transparent electrodes.Herein,we propose and develop a printed embedded metal composite electrode(PEMCE)strategy that enables the fabrication of ultra-thin,highly flexible transparent electrodes with robust mechanical properties.With the flexible transparent electrodes serves as the anodes,flexible/stretchable white OLEDs have been successfully constructed,achieving a current efficiency of up to 77.4 cd A^(-1)and a maximum luminance of 34787 cd m^(-2).The current efficiency of the resulting stretchable OLEDs is the highest ever reported for flexible/stretchable white OLEDs,which is about 1.2 times higher than that of the reference rigid devices based on ITO/glass electrodes.The excellent optoelectronic properties of the printed embedded transparent electrodes and the light extraction effect of the Ag-mesh account for the significant increase in current efficiency.Remarkably,the electroluminescence performance still retains~83%of the original luminance even after bending the device 2000 cycles at a radii of~0.5 mm.More importantly,the device can withstand tensile strains of up to~100%,and even mechanical deformation of 90%tensile strain does not result in a significant loss of electroluminescence performance with current efficiency and luminance maintained at over 85%.The results confirm that the PEMCE strategy is effective for constructing ultra-flexible transparent electrodes,showing great promise for use in a variety of flexible/stretchable electronics.

高分子网状图案制备金属网格透明电极研究进展

高分子网状图案结合不同的金属化方法是制备金属网格透明电极(MMTE)的常用策略。高分子网状图案制备的要点在于线宽和孔隙率的控制,上述参数与MMTE光电性能直接相关。文中综述了高分子网状图案的制备方法及其在MMTE中的应用。目前,高分子静电纺丝网状图案应用较广,可实现低成本、大面积制备MMTE。为了得到高性能的MMTE,需要降低MMTE金属线的宽度/高度(W/H)比值。新兴可穿戴器件要求MMTE具有可伸缩性。进一步对有望用于制备这类MMTE的蛇形图案、剪纸图案、分形图案进行了介绍。

微纳柔性制造与印刷电子材料

微纳加工技术主要应用在光电子和IC领域,随着国际新一轮印刷电子技术的发展,电路线宽越来越细,对印刷电子材料与应用技术提出更高要求,传统印刷术很难实现数微米以下精密电路。针对国际行业研究现状、工艺及最新进展,详细阐述微纳柔性制造技术的原理与特点。基于微纳图形化激光直写光刻技术、卷对卷纳米压印技术及其配套(微纳填充、转印和软压印)技术,以大尺寸透明导电材料的研发为例,微纳柔性制造在106.68 cm幅面上使印刷电路的线宽达到1.5μm。微纳柔性制造方法属于"加法"制造。展望了柔性制造在印刷电子材料产业发展中的前景和需求,指出微纳柔性制造与印刷材料的结合,有可能成为新一轮大尺寸柔性显示与触控、传感器件等产业发展的有力工具和推动性力量。

高性能柔性金属网薄膜透明电极的研究进展

透明导电电极是各种电子器件,包括触摸屏、显示器、薄膜太阳能电池等重要组成部分。在光电器件领域中无论是在产业应用还是基础研究方面,都到了升级换代的关键时刻。金属网透明电极不仅具备了优异的光电特性,而且具有较好的柔韧性,是目前ITO电极在柔性器件中应用的有利替代品。本文主要集中总结了国内外在金属网结构透明电极的制备、性能及应用研究。在使用溶液法制备银纳米线透明电极中如何减小线与线接触电阻、利用模板法制备连续完整的网状电极等是本研究报告的重点。在透过率和面电阻方面,金属网电极相比于商业ITO薄膜更为优异;且金属网作为光电器件中的透明电极时,器件可表现出优异的弯曲机械性甚至可拉伸性。

High-performance ultrathin Ag electrodes by chemical bond anchoring Ag atoms for stretchable organic light-emitting devices

The progress of stretchable organic light-emitting devices(OLEDs)has brought about new possibilities for highly functional wearable electronics.However,the efficiency and durability of stretchable OLEDs have been limited by the performance of stretchable transparent electrodes.Here,we proposed an interface engineering strategy that involves anchoring the growth of silver(Ag)atoms with amine-enriched biomaterials for high-quality stretchable transparent electrodes.The strong interactions between the Ag atom and the amine group enable the uniform Ag electrodes at an ultralow thickness of 7 nm,and provide remarkable mechanical flexibility and strain endurance to the Ag electrodes.The distinct effects of different amino acids were investigated,and a deep understanding of their unique contributions to the film formation process was gained.The resulting ultrathin Ag electrodes exhibit outstanding optoelectrical properties(transmittance of~98% and sheet resistance of~8.7Ω/sq)and excellent stretchability during 500 stretching cycles at 100%strain.Stretchable green phosphorescent OLEDs based on the Ag electrodes have been demonstrated with a current efficiency of up to~70.4 cd/A.Impressively,the devices show excellent stretching stability,retaining~89% of the original luminance and~78% of the original current efficiency after 200 stretching cycles at 100%strain.This work opens up new possibilities for stretchable transparent electrodes,fostering advancements in wearable displays and other innovative flexible devices.

金属纳米线透明导电电极应用于钙钛矿太阳能电池的研究进展

对金属纳米线作为透明导电电极材料的优势及该电极应用于钙钛矿太阳能电池领域所取得的成果进行了综述;重点介绍了银纳米线(AgNW)和铜纳米线(CuNW)的合成方法与透明导电电极的沉积方法,以及金属纳米线透明导电电极对于钙钛矿太阳能电池的光电转换效率等光电性能的影响,并综述了两种金属纳米线材料在导电性、稳定性、抗弯折性以及抗氧化性等方面所存在的局限与改进方法;总结了近年来金属纳米线透明导电电极的研究进展及其在钙钛矿太阳能电池透明导电电极领域的研究成果。最后,对于金属纳米线透明导电电极所具备的优势和所面临的挑战进行了总结,并对该领域的未来发展趋势进行了展望。

金属网格柔性透明导电薄膜研究进展

随着柔性电子器件的发展,柔性显示器、柔性太阳能电池、柔性传感器等产品已经逐步从实验室走向市场。柔性透明导电薄膜作为柔性光电器件不可或缺的重要组成部分,今后其需求量只会不断增加。目前的光电子器件逐渐向大尺寸、轻薄、柔性、可拉伸、低成本等方面发展。氧化铟锡(Indium tin oxide,ITO)是目前使用最广泛的透明导电薄膜,但ITO制备工艺复杂,具有脆性,且铟是稀有金属,储量少,价格昂贵。因此,研制可替代ITO的高性能柔性透明导电薄膜越来越迫切。目前已有研究人员研制出多种可替代ITO的柔性透明导电薄膜,其中基于金属网格的柔性透明导电薄膜是替代ITO的有力竞争者。金属网格柔性透明导电薄膜展示了极好的光电性能和机械灵活性。它最吸引人的地方在于可以独立改变金属网格的线宽和间距,从而在调节薄膜方阻和透光率方面表现出更好的权衡性。目前,已有大量的研究人员研制出可与ITO媲美的金属网格柔性透明导电薄膜。多数研究者通过光刻技术制作出母版,再结合化学镀或电沉积技术进行导电薄膜制作。以光刻技术为基础制备的柔性透明导电薄膜性能良好,但光刻工艺复杂而且设备昂贵。还有研究人员通过其他技术进行研究,如印刷增材制造技术、静电纺丝技术、光子烧结、模板法等,制备的柔性透明导电薄膜性能良好。其中基于印刷增材制造技术制备的柔性透明导电薄膜已经在触摸屏领域实现产业化,有望进一步发展。本文综述了金属网格柔性透明导电薄膜的研究进展及在光电器件中的应用,包括有机太阳能电池、有机发光二极管等,具体讨论了金属网格透明导电薄膜的基本特性、光电性能、制造技术和器件应用,并点明了其制备方法的优劣性,以期为后续的研究提供参考。

NiCoS基柔性透明储能电极的制备及其电化学性能

过渡金属硫化物由于出色的电导率、丰富的活性位点以及多组分的协同效应,是一种理想的电化学储能电极材料。采用简单的电沉积法在氧化铟锡(ITO)衬底表面制备了NiCoS基柔性透明储能电极,研究了NiCo组分对电极的表面形貌、元素组成、电化学性能和透过率等性能参数的影响规律。结果表明,优化的NiCoS基电极在0.05 mA/cm^(2)的电流密度下具有50.2 mF/cm^(2)的面积比电容,1 000次循环后具有良好的循环稳定性和117.71%的比电容保持率。NiCoS基电极作为一种柔性透明的电极,其在波长为550 nm处的透过率为69.70%,表明NiCoS基电极在柔性透明储能器件中具有较大的应用潜力。

优化分析宽带透射的铜网孔阵列透明电极

基于有限时域差分(FDTD)算法优化一类宽带光学透射的金属网格透明电极。设计的Ag、Au和Cu网格阵列在可见光(Vis)波段的透射率约70%,近红外(NIR)波段的透射率约90%。为提高透明电极的效费比和工艺兼容性,选择Cu作为电极材料,并分析封装材料、Cu纳米带表面粗糙度和工艺误差对透射率的影响。结果表明采用高折射率封装材料和增加Cu纳米带的表面粗糙度可以分别增加NIR和Vis波段的透射率,减小NIR波段频带宽度;增加铜纳米带的误差宽度会降低Vis-NIR波段透射特性和减小NIR波段的频带宽度。在封装材料折射率不高于1.5,铜纳米带的表面均方根粗糙度不超过8 nm和误差宽度不超过20 nm时,优化的Cu网格阵列在Vis-NIR波段有较好的透射特性,可作为透明电极应用到光电器件。

基于电场驱动喷射微3D打印和辊轮辅助热压印制造嵌入式金属网格柔性透明导电薄膜

针对现有技术难以实现高性能嵌入式金属网格柔性透明导电薄膜低成本、快速制造的难题,提出了一种基于电场驱动喷射微3D打印和辊轮辅助热压印制造嵌入式金属网格柔性透明导电薄膜新方法,阐述了结合电场驱动喷射微3D打印和辊轮辅助热压印工艺制备透明导电薄膜的基本原理和工艺流程;通过实验揭示了主要工艺参数(打印电压、打印速度、打印气压、压印温度和压印力)对制备嵌入式金属网格柔性透明导电薄膜精度和质量的影响及规律;利用课题组自主研发的电场驱动喷射沉积微纳3D打印机和复合纳米压印光刻机,并结合优化的工艺参数,实现了图案面积70 mm×70 mm、线宽20μm、周期1000μm的嵌入式正方形金属网格柔性透明导电薄膜制造,其方阻为3.62Ω/sq,可见光波段550 nm处的透过率为92.3%,表面粗糙度值为18.81 nm,金属网格与基材的接触等级可达5B,1000次弯折实验后方阻变化率小于8%.