Luminescent photovoltaic generator and a waveguide for use in a photovoltaic generator

摘要

The present invention relates to a luminescent photovoltaic generator (1) and a waveguide for use in such a photovoltaic generator. The photovoltaic generator comprises a photovoltaic cell (4) and a waveguide comprising a transparent matrix (2) having particles of an inorganic luminescent material dispersed therein and/or an inorganic luminescent material disposed at at least one side thereof (6). The waveguide is associated with the photovoltaic cell (4), such that, in use, at least some of the light emitted from the luminescent material passes into the photovoltaic cell (4) to generate a voltage in the cell. In preferred embodiments, the inorganic luminescent material is a line emitter and the emission is due to a forbidden electronic transition within the material. The inorganic luminescent material may be selected from an inorganic phosphor, an inorganic fluorescent material and quantum dots, quantum rods and quantum core/shell systems. The photovoltaic generator (1) is an alternative to or an improvement upon known photovoltaic generators, which generally suffer from a lack of power yield per area.

主权项

1. A photovoltaic generator comprising
a photovoltaic cell; and a waveguide comprising a transparent matrix having particles of an inorganic luminescent material dispersed therein or an inorganic luminescent material disposed at one side thereof, wherein the waveguide is associated with the photovoltaic cell such that at least some of the light emitted from the luminescent material passes into the photovoltaic cell to generate a voltage in the cell; wherein the inorganic luminescent material comprises a first species that absorbs light in the region of 300 nm to 1420 nm, and a second species that emits light at a greater wavelength than the first species absorbs, and energy transfer occurs between the first and second species, such that the inorganic luminescent material absorbs light in the region of 300 nm to 1420 nm, and emits at the greater wavelength, and the light at the greater wavelength, when passed from the waveguide into the photovoltaic cell, is at an appropriate energy to generate the voltage in the photovoltaic cell, an absorption spectrum of the first species has substantially no overlap with an emission spectrum for the second species; wherein the first species are formed by a first set of semiconductor containing quantum particles and the second species are formed by a second set of semiconductor containing quantum particles, the second set of quantum particles having a volumetric mean diameter equal to or larger than a Bohr-radius of an exciton in the semiconductor material from which the second set is made and the first set of quantum particles having a volumetric mean diameter that is less than a Bohr-radius of an exciton in the semiconductor material from which the first set is made; and wherein a greater number of the first species of said quantum particles is present in the inorganic luminescent material relative to a number of the second species of said quantum particles for reducing re-absorption of emitted light.