Inorganic luminescent materials for solar radiation conversion devices

Abstract

A device for converting solar radiation is described wherein the device comprises an inorganic luminescent material comprising a host material doped with Mn5+ ions for converting radiation of the UV and/or visible part of the electromagnetic spectrum into radiation of the near-infrared radiation part of the electromagnetic spectrum, preferably the infrared part between 1150 nm and 1250 nm, preferably around 1190 nm (the infrared emission peak of Mn5+); or, an amorphous host material doped with Sm2+ or Tm2+ ions, the amorphous host material including the elements Al, Si, O and N (SiAION) for converting radiation of the UV and/or visible part of the electromagnetic spectrum into radiation of a longer wavelength, preferably a longer wavelength between 650 n and 800 nm or a longer wavelength of around 1140 n; and, at least one photovoltaic device for converting at least part of the converted radiation into electrical power.

What is claimed is: 
     
         1 . Device for converting solar radiation comprising:
 an inorganic luminescent material comprising a doped host material,   wherein the doped host material is doped with Mn 5+  ions for converting radiation of the UV, visible and/or at least part of the near infrared band of the solar spectrum into radiation of a predetermined near-infrared band, preferably the near-infrared band between 1150 nm and 1250 nm, more preferably between 1180 nm and 1200 nm (the band around the emission peak of Mn 5+ ); or,   wherein the doped host material includes elements Al, Si, O and N and wherein the doped host material is doped with Sm 2+  and/or Tm 2+  ions for converting radiation of the UV, visible and/or at least part of the near infrared band of the solar spectrum into radiation of a predetermined visible red band; preferably the visible red band between 650 nm and 800 nm (the band around the emission peak of Mn2 + ); and/or, or into radiation of a predetermined near-infrared band, preferably the near-infrared band between 1100 and 1200 nm, more preferably between 1130 nm and 1150 nm (the band around the emission peak of Tm 2+  and,   at least one photovoltaic device for converting at least part of the converted radiation into electrical power.   
     
     
         2 . The device according to  claim 1  wherein the doped host material comprises doped microparticles and/or nanoparticles, preferably the microparticles having an average size between 1 and 200 micron, preferably between 1 and 100 micron, more preferably between 1 and 30 micron; and the nanoparticles having an average size between 1 nm and 800 nm, preferably between 2 nm and 600 nm, more preferably between 3 nm and 500 nm, yet more preferably 10 and 300 nm. 
     
     
         3 . The device according to  claim 1 , wherein the doped host material includes a layer of microparticles and/or nanoparticles dispersed in a transparent matrix material, preferably an organic matrix material or an inorganic matrix material. 
     
     
         4 . The device according  claim 1 , wherein the doped host material includes a thin-film layer, preferably a crystalline thin-film layer (e.g. a nanocrystalline, microcrystalline or polycrystalline thin-film layer) or an amorphous thin-film layer. 
     
     
         5 . The device according to  claim 1 , wherein the dopant concentration of the doped host material is in a range of 0.01 and 90%. 
     
     
         6 . The device according to  claim 1 , wherein the Tm 2+  and/or Sm 2+  doped host material is an amorphous thin-film layer having a haze smaller than 3%, preferably smaller than 2%. 
     
     
         7 . The device according to  claim 1 , wherein the Mn 5+  doped host material comprises a ternary and/or a quaternary inorganic material, preferably the ternary material being defined by the general formula M 3 (XO 4 ) 2  wherein M=Ca, Ba, Sr and X=P, As, V and the quaternary material being defined by the general formula M 5 (XO 4 ) 3 Y wherein M=Ca, Ba, Sr and X=P, As, V and Y=OH, Cl, F. 
     
     
         8 . The device according to  claim 1 , wherein the at least one photovoltaic device is configured to transform radiation generated by the luminescent material, preferably radiation in the visible red/near infrared band between 650 nm and 800 nm or the near-infrared band between 1100 and 1250 nm into electric power, more preferably the photovoltaic device comprising one or more layers of a IV, III-V and/or a II-VI semiconductor, preferably the one or more layers comprising silicon, gallium arsenide, cadmium telluride indium phosphide, copper indium gallium (di)Selenide (CIGS) and/or copper Indium (di)selenide (CIS). 
     
     
         9 . The device according to  claim 1 , wherein the luminescent inorganic material is part of or associated with a waveguide structure, the waveguide structure being configured to guide at least part of the converted radiation to the at least one photovoltaic device, preferably the waveguide structure being a planar waveguide structure including a first (top) surface and a second (bottom) surface and one or more edges, wherein the at least one photovoltaic device is located at one of the edges of the planar waveguide structure. 
     
     
         10 . The device according to  claim 9  wherein the waveguide structure comprises a transparent organic or inorganic material having a first surface and a second surface, preferably the inorganic luminescent material being provided over or on at least part of the first surface and/or second surface of the waveguide structure; and/or, wherein the inorganic luminescent material is embedded in the waveguide structure. 
     
     
         11 . The device according to  claim 9 , wherein the waveguide structure comprises a first pane and a second pane and at least one spacer structure, preferably a spacer structure at the periphery of the first and second pane, for providing a predetermined separation between the first and second pane, preferably the first and/or second pane including an organic or inorganic, e.g. glass, pane, wherein the inorganic luminescent material is provided over at least one of the surfaces of the first and/or second pane, the space defined by the first and second glass defining a waveguide structure for guiding at least part of the radiation generated by the luminescent layer towards at least one photovoltaic device. 
     
     
         12 . The device according to  claim 11 , wherein one or more optical layers are provided over the inner or outer surface of the first and/or second pane, the one or more optical layers including one or more reflecting and/or refracting layers for radiation generated by the inorganic luminescent material, preferably for radiation in the visible red band being between 650 nm and 800 nm; and/or, or the near-infrared band being between 1100 and 1250 nm. 
     
     
         13 . The device according to  claim 1  wherein at least part of the luminescent inorganic material is provided over a light receiving face of the at least one photovoltaic device; and/or, wherein the at least one photovoltaic device comprises one or more thin-film layers comprising the luminescent inorganic material. 
     
     
         14 . A window assembly comprising a device for converting solar radiation according to  claim 1 . 
     
     
         15 . A window assembly for converting solar radiation comprising:
 at least a first window pane and a second window pane and at least one spacer structure for providing a predetermined separation between the at least first and second window pane,   an inorganic luminescent material for converting radiation of a UV, visible and/or (part of) the near infrared band of the solar spectrum into radiation of a predetermined visible red and/or near infrared band, wherein the first window pane, the second window pane; and/or, the space between the first and second window pane define one or more waveguide structures for guiding at least part of the radiation generated by the luminescent material towards at least one photovoltaic device; and,   one or more photovoltaic devices positioned along one or more edges of the first and second window pane, the light receiving surface of the PV devices being oriented to receive radiation emitted by the luminescent material.   
     
     
         16 . The window assembly according to  claim 15 , wherein the inorganic luminescent material is provided as a thin-film layer over or on at least one of the surfaces of the first and/or second window pane; 
     
     
         17 . The window assembly according to  claim 15 , wherein one or more optical layers are provided over or on at least part of the surfaces of the first and/or second window pane, the one or more optical layers including at least one reflecting and/or refractive layer for radiation generated by the inorganic luminescent material, preferably for radiation in the visible red band being between 650 nm and 800 nm; and/or, or the near-infrared band being between 1100 and 1250 nm.