Quantum Rod Film (QRF) – Optical properties and stability

J. Niehaus, S. Becker, T. Jochum, H. Weller

Keywords: quantum dot, quantum rod, film, sheet


We will show the optimization steps during the development of green and red emitting rods performed with the flow reactor. We are now able to produce green emitting rods with a quantum yield for 98% and red emitting rods with 88%. In addition changes in the reaction conditions also influence the aspect ratio of the rods. These particles were used for experiments with different polymer matrixes in order to form a quantum rod film suitable for display applications. To achieve this goal the particles were modified on the surface so that a homogeneous dispersion in the corresponding monomer can be achieved. Afterwards to monomer was polymerized and the optical properties were measured. The measurements of the nanorod films have shown that the quantum yield of the particles can be maintained. Measurements up to 85% have been achieved. A small red shift of the emission maximum was also observed. This problem can be solved by using rods with shorter emission wavelength or by variation of the polymerization conditions. These polymer films were used for stability studies. They were kept at a higher temperature in the oven and the QY was measured as a function of time. The nanorods showed a better stability than the spherical quantum dots. This is very important as a quantum rod film without barrier layers against oxygen and moisture might be possible.