Enhanced output efficiency of GaN-based light-emitting diodes by silver nanowires-induced localized surface plasmon

The authors investigated the localized surface plasmon (LSP)-enhanced light output efficiency of GaN-based light-emitting diodes (LEDs) fabricated with indium-tin-oxide (ITO)/silver nanowire (AgNWs) transparent conductive electrodes (TCEs). The ITO/AgNWs TCE yielded optical transmittance of 91.7% at a wavelength of 450 nm, a sheet resistance of 16.4 omega/sq, and a specific contact resistance of 1.3 x 10(-3) omega cm(2). Notably, the LEDs fabricated with ITO/AgNWs TCE showed 51.5% greater output power than the reference LEDs fabricated with ITO TCE. This could be due to the combined effects of higher optical transparency and, more importantly, vertical out-coupling of the localized surface plasmon (LSP) resonance with the trapped wave-guided mode of light.11Nsciescopuskc

Functional hybrid indium-tin-oxide transparent conductive electrodes for light-emitters

Recently, new types of nano-materials such as carbon nanotubes, graphene, and silver nanowires have been demonstrated as next-generation transparent conductive electrodes (TCEs) in organic and inorganic light-emitting devices owing to their unique functional features such as mechanical flexibility, improved electrical conductivity, high optical transmittance across the entire wavelength range, and surface plasmonic effects. Functional TCEs fabricated with indium-tin-oxide (ITO) materials were developed in this research to maximize the output efficiency of III-nitride light-emitting diodes (LEDs). The functional ITO TCE consists of a small area portion (∼2%) of e-beam evaporated ITO (acting as an Ohmic patch) and a sputtered ITO over-layer (acting as a current spreader). They yield excellent optical transmittance of 93.1% at 450 nm, sheet resistance of 24.2 Ω/sq, and specific contact resistance of 1.5 × 10−3 Ωcm2. More strikingly, LEDs fabricated with functional hybrid ITO show 62% greater output power than the reference LEDs fabricated with conventional ITO. This was due to the functional feature of hybrid ITO, i.e., a significant vertical out-coupling of laterally guided modes at near the e-beam evaporated Ohmic patch (because of the generated trapezoidal cylindrical surface textures on the ITO surface), enhanced uniform current spreading as well as to the improved TCE performances. © 2017 Elsevier B.V2

Structure-inherent near-infrared bilayer nanovesicles for use as photoacoustic image-guided chemo-thermotherapy

Image-guided therapy, combined with imaging and therapeutic action, forms an attractive system because it can induce outstanding effects at focused locations. However, the conventional liposomes-based system cannot figure in therapeutic or imaging roles themselves, thereby causing the disadvantage of their biological unavailability as a theragnosis tool. Herein, the structure-inherent near-infrared bilayer nanovesicles are fabricated with amphiphilic heptamethine cyanine dye, PEG conjugated heptamethine cyanine dye, and gemcitabine (NEPCG) is developed for the novel photoacoustic image-guided chemo-thermotherapy system. The organic structure-inherent near-infrared bilayer nanovesicles are self-assembled and exhibit a liposome-like bilayer structure. Furthermore, NEPCG showed the high photoacoustic signal (PA) due to the specific accumulation in the tumor site. Delivered NEPCG than displayed concurrent chemotherapy and photothermal therapy (PTT) effects against cancer, triggered by PA imaging with minimal side effects. In vitro and in vivo experiments show that NEPCG can be used as outstanding contrast agents and completely obliterate the tumor without reoccurrence under laser irradiation. Therefore, this work presents the potential for the realization of unprecedented structure-inherent near-infrared bilayer nanovesicles as highly accurate and effective theragnostic tools in clinical fields.11Nsciescopu