Photoluminescence quenching device and display using photoluminescence quenching devices
View Patent ↗A display having a hole barrier layer and/or a electron barrier layer, whereby the hole barrier layer and/or the electron barrier layer are disposed between an emitter layer and a first electrode layer or a second electrode layer of the display. The highest occupied molecule orbital of the hole barrier layer is energetically lower than highest occupied molecule orbital of the emitter layer and/or the lowest unoccupied molecule orbital of the electron barrier layer is energetically higher than the lowest unoccupied molecule orbital of the emitter layer. By arranging the energy levels of the molecule orbitals of the hole barrier layer and/or the electron barrier layer, barriers can be created to prevent the injection of unwanted charge carriers in the reverse direction during re-emissive operation of the display.
1. A display based on a photoluminescence quenching device (PQD), the display comprising:
a substrate;
an emitter layer;
a first electrode layer, which is transparent and is arranged on a front side of the emitter layer;
a second electrode layer, which is disposed on the backside of the emitter layer; and
an electron barrier layer comprising phenylenediamine derivatives and a hole barrier layer where the hole barrier layer and the electron barrier layer are respectively disposed between the emitter layer and one of the first electrode layer and second electrode layer, wherein a highest occupied molecule orbital of the hole barrier layer is energetically lower than a highest occupied molecule orbital of the emitter layer and a lowest unoccupied molecule orbital of the electron barrier layer is energetically higher than a lowest unoccupied molecule orbital of the emitter layer,
wherein the lowest unoccupied molecule orbital of the emitter layer corresponds to the lowest unoccupied molecule orbital of the hole barrier layer and the highest occupied molecule orbital of the electron baffler layer corresponds to the highest occupied molecule orbital of the emitter layer, whereby the first electrode layer forms a cathode and the second electrode layer forms an anode during re-emissive operation of the display, and the first electrode layer forms the anode and the second electrode layer forms a cathode during emissive operation of the display; and
wherein the hole barrier layer comprises at least one compound selected from a group consisting of oxadiazole derivatives, oxazole derivatives, triazole derivatives and quinoxaline derivatives and/or at least one compound selected from a group consisting of naphthalene carboxylic acid imide derivatives, naphthalene dicarboxylic acid diimide derivatives and wide-bandgap inorganic semiconductors.
2. The display of claim 1 , wherein an energy difference between the highest occupied molecule orbital of the electron barrier layer and the lowest unoccupied molecule orbital of the electron barrier layer and an energy difference between the highest occupied molecule orbital of the hole barrier layer and the lowest unoccupied molecule orbital of the hole barrier layer each amount to at least about 3.3 eV.
3. The display of claim 1 , wherein the hole barrier layer is at least one of tin oxide, titanium oxide, zinc oxide, zirconium oxide, tantalum oxide, zinc sulphide and zinc selenide.
4. The display of claim 1 , wherein the hole barrier layer is disposed on a side of the emitter layer that faces towards the substrate and the electron barrier layer is disposed on a side of the emitter layer that faces away from the substrate.
5. A photoluminescence quenching device (PQD), comprising an organic light emitting material;
a first electrode which is transparent and is located on a front side of the organic light emitting material; and
a second electrode which is located on a back side of the organic light emitting material wherein the PQD comprises an electron barrier layer comprising phenylenediamine derivatives and a hole barrier layer disposed between the light emitting material and one of the first electrode or the second electrode, respectively, and a highest occupied molecule orbital of the light emitting material and a lowest occupied molecule orbital of the electron barrier layer is energetically higher than a lowest unoccupied molecule orbital of the light emitting material,
wherein the lowest unoccupied molecule orbital of the light emitter material corresponds to the lowest unoccupied molecule orbital of the hole barrier layer and the highest occupied molecule orbital of the electron barrier layer corresponds to the highest occupied molecule orbital of the emitter material, whereby the first electrode forms a cathode and the second electrode forms an anode during re-emissive operation of the PQD and the first electrode forms the anode and the second electrode forms the cathode during emissive operation of the PQD; and
wherein the hole barrier layer comprises at least one compound selected from a group consisting of oxadiazole derivatives, oxazole derivatives, triazole derivatives and quinoxaline derivatives and/or at least one compound selected from a group consisting of naphthalene carboxylic acid imide derivatives, naphthalene dicarboxylic acid diimide derivatives and wide-bandgap inorganic semiconductors.
6. The PQD of claim 5 , wherein an energy difference between the highest occupied molecule orbital of the electron barrier layer and the lowest unoccupied molecule orbital of the electron barrier layer and an energy difference between the highest occupied molecule orbital of the hole barrier layer and the lowest unoccupied molecule orbital of the hole barrier layer each amounts to at least about 3.3 eV.
7. The display of claim 5 , wherein the hole barrier layer is at least one of tin oxide, titanium oxide, zinc oxide, zirconium oxide, tantalum oxide, zinc sulphide and zinc selenide.