Self-assembled molecules as efficient selective contacts in translucent quantum-dot light emitting diodes

[eng] Since the last two decades, nanotechnology has been revolutionary for representing small solutions to the big problems. Nanoscience and Nanotechnology spread from the area of Electronics, Energy and Environment to Biomedicine, Food or Textile where it has made possible to selectively target the cells to repair the damaged genes. It has also made possible to convert more sunlight into energy with efficient solar panels. Nanostructured materials make faster and more efficient microchips. It also contributes to make biosensors to detect pollutants in bodies. Today, nanomaterials have made possible to fabricate the LEDs of different colours. Colloidal quantum dots technology has drawn a huge attention in the academia and industry since last decade. Quantum dots are also called “Artificial Atoms” because they have discrete energy levels just like atoms. QDs are zero dimensional particles showing quantum confinement effect which means that their size comparable to Bohr radius and their colour can change with their size which is typically between 2-10 nm. On the other hand, these materials show excellent optical properties including high absorption, strong and narrow emission with high colour purity making them suitable for various applications. Perovskites are crystalline materials with the structure of calcium titanium oxide. They are extensively used for several applications because of their easy manufacturing process, abundance, low cost, and great flexibility. Metal halide perovskites are popular for their vast range of application in optoelectronic devices while metal oxide perovskites are widely used in chemical, electrochemical and photocatalysis. Self-assembled molecules (SAMs) are a class of materials which can attach to any substrate modifying the work function of the electrode for their diverse application. They consist of three components including terminal group, spacer group and anchoring group. SAMs are used to make organic and perovskite solar cells with better efficiency and stability. Nowadays, ...