Session Chair: Daniel Chua, National University of Singapore
10:30am - 11:00am Invited
Graphene Transparent Electrode for Flexible Electronics
Yonsei University, South Korea
Graphene, a monolayer of carbon atoms arranged in a honeycomb structure, is a unique material with outstanding mechanical property, good optical transmittance and electrical conductivity that may be useful in flexible transparent electrode. The versatile properties of graphene make it suitable for use in flexible and transparent electronics, optoelectronics, energy storage and conversion devices. In this talk, I will present recent progress in methods for graphene growth, modification, and transfer, and the uses of graphene as a transparent conducting electrode in flexible electronic devices.
11:00am - 11:30am Invited
Novel Flexible Transparent Electrodes Based on Silver Nanowires
University of California, Los Angeles, United States
Silver nanowire (AgNW) –polymer composite electrodes have been developed as a viable replacement for ITO/glass and ITO/PET, with added benefits of high mechanical flexibility. The sheet resistance can be adjusted in the range from 5-50 W/sq with transmission ranging from 70 to 90%. The surface roughness is generally <2 nm, suitable for the fabrication of thin film electronic devices. The composite electrode can be further tailored to maximize the device performance. Integrated OLED substrate will be presented comprising light scattering nanoparticle to increase the light extraction efficiency by up to 2.5X.
11:30am - 11:45am Oral
Printable Flexible Transparent Conductive Films based on Silver Nanowires: Fabrication and Optoelectronic Properties
Dongdong LI1, Wen-Yong LAI1,2, Wei HUANG1,2
1Nanjing University of Posts and Telecommunications, China; 2Nanjing Tech University (Nanjing Tech), China
Printed electronics offer a wide-variety of advantages in the development of low-cost, large-area, and flexible optoelectronic devices. In combination with the solution processable metallic nanowires (NWs), printable transparent conductive films (TCFs) can simultaneously exhibit high mechanical flexibility, low cost, and comparable optoelectronic properties to commonly used indium tin oxide-based TCFs. This paper presents a roll-to-roll compatible screen printing technique for the fabrication of large-scaled flexible Ag NW TCFs. The ink formulation, substrate treatment, patterning, post-processing, and potential application in supercapacitors are systematically investigated. An excellent mechanical flexibility has been demonstrated by testing the photoelectric stability of the TCFs under severe mechanical strain such as bending, retortion, or stretching. High optical transmittance and low sheet resistivity of the as-prepared TCFs meet the requirement for their further applications in optoelectronic devices, even though undergoing severe mechanical deformation. The rational combination of the printed technique with emerging transparent conductive materials is believed to be helpful for the development of the next-generation printable flexible electronics.
11:45am - 12:00pm Oral
Scalable, Highly Stable and Foldable Transparent Conducting Nanopaper
Jia Qing XIONG, Shao Hui LI, Wen Bin KANG, Meng Fang LIN, Pooi See LEE
Nanyang Technological University, Singapore
Transparent conducting electrode (TCE) is one indispensable element for various optoelectronic applications such as solar cell, touch panel, light-emitting diodes, electrochromics, etc. Ag nanowires (Ag NWs) percolating TCE is now being actively developed for deformable applications owing to their high conductivity and strong endurance against deformations like stretching, bending and even folding. However, Ag NWs electrodes are very unstable in the air that with natural light and humidity, seriously accelerated failure will be generated especially suffer the ultraviolet (UV) illumination. Thus, the long-term reliability of Ag NWs based TCE that depend on the foldable substrates and over-coating layers are a pressing need to be realized. Nanocellulose, a ubiquitous natural resource, is attracting escalating attention recently for foldable electronics due to its extreme flexibility, excellent mechanical strength, and outstanding transparency. We have developed a cellulose based transparent conductive nanopapers (TCNs) for the solid state foldable electrochromic device that delivers the state-of-the-art electro-optical performance. Here, large-scale TCNs were realized by bar-coating, and scalable protective layer such as CNTs and graphene were achieved to improve the chemical and mechanical stability, making the TCNs a versatile candidate for various electronics applications.