High-Performance Flexible Transparent Electrode with an Embedded Metal Mesh Fabricated by Cost-Effective Solution Process.

A new structure of flexible transparent electrodes is reported, featuring a metal mesh fully embedded and mechanically anchored in a flexible substrate, and a cost-effective solution-based fabrication strategy for this new transparent electrode. The embedded nature of the metal-mesh electrodes provides a series of advantages, including surface smoothness that is crucial for device fabrication, mechanical stability under high bending stress, strong adhesion to the substrate with excellent flexibility, and favorable resistance against moisture, oxygen, and chemicals. The novel fabrication process replaces vacuum-based metal deposition with an electrodeposition process and is potentially suitable for high-throughput, large-volume, and low-cost production. In particular, this strategy enables fabrication of a high-aspect-ratio (thickness to linewidth) metal mesh, substantially improving conductivity without considerably sacrificing transparency. Various prototype flexible transparent electrodes are demonstrated with transmittance higher than 90% and sheet resistance below 1 ohm sq(-1) , as well as extremely high figures of merit up to 1.5 × 10(4) , which are among the highest reported values in recent studies. Finally using our embedded metal-mesh electrode, a flexible transparent thin-film heater is demonstrated with a low power density requirement, rapid response time, and a low operating voltage.

[1]  Zhenan Bao,et al.  Organic light-emitting diodes on solution-processed graphene transparent electrodes. , 2010, ACS nano.

[2]  Yi Cui,et al.  Performance enhancement of metal nanowire transparent conducting electrodes by mesoscale metal wires , 2013, Nature Communications.

[3]  Chaoyi Yan,et al.  High-efficiency transfer of percolating nanowire films for stretchable and transparent photodetectors. , 2014, Nanoscale.

[4]  Wei Xu,et al.  Highly flexible and transparent film heaters based on polyimide films embedded with silver nanowires , 2015 .

[5]  Jianguo Liu,et al.  In situ fabrication of highly conductive metal nanowire networks with high transmittance from deep-ultraviolet to near-infrared. , 2015, ACS nano.

[6]  Yi Cui,et al.  Self-limited plasmonic welding of silver nanowire junctions. , 2012, Nature materials.

[7]  Stephen Y. Chou,et al.  Imprint of sub-25 nm vias and trenches in polymers , 1995 .

[8]  S. Kirchmeyer,et al.  Scientific importance, properties and growing applications of poly(3,4-ethylenedioxythiophene) , 2005 .

[9]  Yi Cui,et al.  Electrospun metal nanofiber webs as high-performance transparent electrode. , 2010, Nano letters.

[10]  K. Novoselov,et al.  Graphene-based liquid crystal device. , 2008, Nano letters (Print).

[11]  K. R. Atkinson,et al.  Strong, Transparent, Multifunctional, Carbon Nanotube Sheets , 2005, Science.

[12]  Woo-Seok Yang,et al.  Uniformly Interconnected Silver‐Nanowire Networks for Transparent Film Heaters , 2013 .

[13]  L. Jay Guo,et al.  Organic Solar Cells Using Nanoimprinted Transparent Metal Electrodes , 2008 .

[14]  Benjamin J Wiley,et al.  The Growth Mechanism of Copper Nanowires and Their Properties in Flexible, Transparent Conducting Films , 2010, Advanced materials.

[15]  Qingshui Xie,et al.  Copper Nanowires as Fully Transparent Conductive Electrodes , 2013, Scientific Reports.

[16]  Rong Yang,et al.  Nanoimprint-assisted fabrication of high haze metal mesh electrode for solar cells , 2014 .

[17]  Yang Yang,et al.  Solution-processed flexible transparent conductors composed of silver nanowire networks embedded in indium tin oxide nanoparticle matrices , 2012, Nano Research.

[18]  U. Schubert,et al.  Inkjet Printing of Narrow Conductive Tracks on Untreated Polymeric Substrates , 2008 .

[19]  Thomas M. Higgins,et al.  Silver Nanowire Networks as Flexible, Transparent, Conducting Films: Extremely High DC to Optical Conductivity Ratios. , 2009, ACS nano.

[20]  A. Carella,et al.  Highly flexible transparent film heaters based on random networks of silver nanowires , 2012, Nano Research.

[21]  Zhenan Bao,et al.  Highly Conductive and Transparent PEDOT:PSS Films with a Fluorosurfactant for Stretchable and Flexible Transparent Electrodes , 2012 .

[22]  Zhibin Yu,et al.  Silver Nanowire‐Polymer Composite Electrodes for Efficient Polymer Solar Cells , 2011, Advanced materials.

[23]  Albert Polman,et al.  Transparent conducting silver nanowire networks. , 2012, Nano letters.

[24]  Duckjong Kim,et al.  Transparent flexible heater based on hybrid of carbon nanotubes and silver nanowires , 2013 .

[25]  K. Ellmer.  Past achievements and future challenges in the development of optically transparent electrodes , 2012, Nature Photonics.

[26]  Qibing Pei,et al.  Highly Flexible Silver Nanowire Electrodes for Shape‐Memory Polymer Light‐Emitting Diodes , 2011, Advanced materials.

[27]  S. Nahm,et al.  The manufacture of a transparent film heater by spinning multi-walled carbon nanotubes , 2011 .

[28]  Yi Cui,et al.  A transparent electrode based on a metal nanotrough network. , 2013, Nature nanotechnology.

[29]  Liangbing Hu,et al.  Emerging Transparent Electrodes Based on Thin Films of Carbon Nanotubes, Graphene, and Metallic Nanostructures , 2011, Advanced materials.

[30]  Byeong Wan An,et al.  Stretchable and transparent electrodes using hybrid structures of graphene-metal nanotrough networks with high performances and ultimate uniformity. , 2014, Nano letters.

[31]  J. Shin,et al.  Uniformly embedded silver nanomesh as highly bendable transparent conducting electrode , 2015, Nanotechnology.

[32]  Dong Sui,et al.  Flexible and transparent electrothermal film heaters based on graphene materials. , 2011, Small.

[33]  R. Kaner,et al.  Solution-processed transparent electrodes , 2011 .

[34]  Wen‐Di Li,et al.  Nanostructure transfer using cyclic olefin copolymer templates fabricated by thermal nanoimprint lithography , 2014 .

[35]  Chongwu Zhou,et al.  The race to replace tin-doped indium oxide: which material will win? , 2010, ACS nano.

[36]  R. B. Tahar,et al.  Tin doped indium oxide thin films: Electrical properties , 1998 .

[37]  Kenji Shinozaki,et al.  Strongly adhesive and flexible transparent silver nanowire conductive films fabricated with a high-intensity pulsed light technique , 2012 .

[38]  Yi Cui,et al.  Scalable coating and properties of transparent, flexible, silver nanowire electrodes. , 2010, ACS nano.

[39]  Moon Kyu Kwak,et al.  Photo–Roll Lithography (PRL) for Continuous and Scalable Patterning with Application in Flexible Electronics , 2013, Advanced materials.

[40]  Liangbing Hu,et al.  Approaching the limits of transparency and conductivity in graphitic materials through lithium intercalation. , 2014, Nature communications.

[41]  S. Ko,et al.  Nonvacuum, maskless fabrication of a flexible metal grid transparent conductor by low-temperature selective laser sintering of nanoparticle ink. , 2013, ACS nano.

[42]  Z. Ren,et al.  Uniform Self‐Forming Metallic Network as a High‐Performance Transparent Conductive Electrode , 2014, Advanced materials.

[43]  Moon Kyu Kwak,et al.  Continuous phase-shift lithography with a roll-type mask and application to transparent conductor fabrication , 2012, Nanotechnology.

[44]  Ritu Gupta,et al.  Large area solution processed transparent conducting electrode based on highly interconnected Cu wire network , 2014 .

[45]  R. Gordon.  Criteria for Choosing Transparent Conductors , 2000 .

[46]  Shui-Tong Lee,et al.  High-performance flexible organic light-emitting diodes using embedded silver network transparent electrodes. , 2014, ACS nano.

[47]  G. Crawford,et al.  Strain-dependent electrical resistance of tin-doped indium oxide on polymer substrates , 2000 .

[48]  June-Ki Park,et al.  Transparent Film Heater Using Single‐Walled Carbon Nanotubes , 2007 .

[49]  Julia R Greer,et al.  Fabrication and microstructure control of nanoscale mechanical testing specimens via electron beam lithography and electroplating. , 2010, Nano letters.

[50]  Dong Yun Lee,et al.  Flexible and transparent metallic grid electrodes prepared by evaporative assembly. , 2014, ACS applied materials & interfaces.

[51]  Paul W. Leu,et al.  Hierarchical graphene/metal grid structures for stable, flexible transparent conductors. , 2015, ACS nano.

[52]  S. Ko,et al.  Very long Ag nanowire synthesis and its application in a highly transparent, conductive and flexible metal electrode touch panel. , 2012, Nanoscale.

[53]  Satyen K. Deb,et al.  Stand-alone photovoltaic-powered electrochromic smart window , 2001 .

[54]  Se-Young Jeong,et al.  Cu Mesh for Flexible Transparent Conductive Electrodes , 2015, Scientific Reports.

[55]  Gang Li,et al.  Fused silver nanowires with metal oxide nanoparticles and organic polymers for highly transparent conductors. , 2011, ACS nano.

[56]  K. Suganuma,et al.  Transparent electrodes fabricated via the self-assembly of silver nanowires using a bubble template. , 2012, Langmuir : the ACS journal of surfaces and colloids.

[57]  Ritu Gupta,et al.  Metal wire network based transparent conducting electrodes fabricated using interconnected crackled layer as template , 2014 .

[58]  L. Jay Guo,et al.  Nanoimprinted Semitransparent Metal Electrodes and Their Application in Organic Light‐Emitting Diodes , 2007 .

[59]  A. Polman,et al.  Solution‐Grown Silver Nanowire Ordered Arrays as Transparent Electrodes , 2016, Advanced materials.

[60]  H. Duan,et al.  Resolution limits of electron-beam lithography toward the atomic scale. , 2013, Nano letters (Print).

[61]  A. Ferrari,et al.  Graphene Photonics and Optoelectroncs , 2010, CLEO 2012.

[62]  L. Zhi,et al.  Rod‐Coating: Towards Large‐Area Fabrication of Uniform Reduced Graphene Oxide Films for Flexible Touch Screens , 2012, Advanced materials.

[63]  Jong-Hyun Ahn,et al.  High-performance graphene-based transparent flexible heaters. , 2011, Nano letters.

[64]  Zhigang Suo,et al.  Highly stretchable and transparent nanomesh electrodes made by grain boundary lithography , 2014, Nature Communications.

[65]  Doyoung Byun,et al.  Invisible metal-grid transparent electrode prepared by electrohydrodynamic (EHD) jet printing , 2013 .

[66]  John A. Rogers,et al.  Omnidirectional Printing of Flexible, Stretchable, and Spanning Silver Microelectrodes , 2009, Science.

[67]  Ritu Gupta,et al.  Spray coating of crack templates for the fabrication of transparent conductors and heaters on flat and curved surfaces. , 2014, ACS applied materials & interfaces.

[68]  Kyung Hyun Choi,et al.  Multi-nozzle electrohydrodynamic inkjet printing of silver colloidal solution for the fabrication of electrically functional microstructures , 2011 .

[69]  Jing Sun,et al.  Synthesis of ultralong copper nanowires for high-performance transparent electrodes. , 2012, Journal of the American Chemical Society.

[70]  Kyung Hyun Choi,et al.  Direct printing of copper conductive micro-tracks by multi-nozzle electrohydrodynamic inkjet printing process , 2012 .

[71]  Alex K.-Y. Jen,et al.  Metal grid/conducting polymer hybrid transparent electrode for inverted polymer solar cells , 2010 .

[72]  D. Choi,et al.  High-durable AgNi nanomesh film for a transparent conducting electrode. , 2014, Small.