Optimization of nano-honeycomb structures for flexible w-LEDs

This study presents the low cost fabrication of flexible white-light-emitting diodes (w-LEDs) with nano-honeycomb-structured phosphor films. Extending the dimensions of the nano-honeycomb structures improved the color uniformity of the flexible samples, and the 950-nm pattern sample demonstrated optimal color uniformity because this nano-pattern exhibited an excellent diffusion ability owing to its pitch size. In addition to color uniformity, the use of this nano-pattern improved the luminous efficiency. The 750-nm pattern exhibited the highest luminous efficiency (235.8 lm/W), which was approximately 7% higher than that exhibited by a non-patterned phosphor film sample. Thus, flexible w-LEDs with nano-honeycomb structure optimization have great potential to be used as next-generation lighting sources.