Photovoltaic device and method for preparing the same

Abstract

The present invention relates to a photovoltaic device, especially a hybrid solar cells, comprising at least one layer comprising evaporated fluoride and/or acetate; and to a method for preparing the same.

1 . Photovoltaic device having at least one layer comprising evaporated fluoride and/or acetate.  
     
     
         2 . Photovoltaic device according to  claim 1 , further having a solid conjugated semiconductor comprising a hole transport material, wherein the hole transport material is mixed with a dopant.  
     
     
         3 . Photovoltaic device according to  claim 1  or  2 , further comprising a blend or bilayer structure of conductive organic and/or polymer materials, wherein one component is a p-type conductor and the other one is a n-type conductor.  
     
     
         4 . Photovoltaic device according to any of the preceding claims, wherein the evaporated fluoride is an alkali or alkaline earth metal fluoride.  
     
     
         5 . Photovoltaic device according to any of the preceding claims, wherein the evaporated acetate is an alkali metal acetate.  
     
     
         6 . Photovoltaic device according to any of the preceding claims, further comprising a semi-conductor oxide layer sensitized with a dye, preferably a ruthenium complex dye.  
     
     
         7 . Photovoltaic device according to any of the preceding claims, wherein the evaporated layer containing fluoride and/or acetates is evaporated on top of the semiconductor oxide layer and/or on top of a layer of the hole transport material and/or an top of a transparent conductive oxide electrode.  
     
     
         8 . Photovoltaic device according to  claim 7 , wherein the semiconductor oxide layer is titanium dioxide.  
     
     
         9 . Photovoltaic device according to any of the preceding claims, wherein the evaporated layer has a thickness of about 0.5 to about 30 nm, preferably about 0.5 to about 15 nm.  
     
     
         10 . Photovoltaic device according to any of the preceding claims, wherein fluorides and/or acetates evaporated on different layers of the device have different counter cations.  
     
     
         11 . Photovoltaic device according to  claim 10 , wherein the evaporated layer which is evaporated on the semiconductor oxide layer comprises lithium fluoride having a thickness of about 5 nm, and the evaporated layer which is evaporated on the hole transport material comprises cesium fluoride having a thickness of about 15 nm.  
     
     
         12 . Photovoltaic device according to any of the preceding claims, wherein the hole transport material is represented by formula (I)  
       
         
           
           
               
               
           
         
       
       wherein R in each occurrence is dependently selected from hexyl and ethylhexyl within the wt % ratio of hexyl:ethylhexyl being about 40:about 60, or represented by formula (II)  
       
         
           
           
               
               
           
         
       
       or represented by formula (III)  
       
         
           
           
               
               
           
         
       
     
     
         13 . Photovoltaic device according to any of the preceding claims wherein the semiconductor oxide layer is porous.  
     
     
         14 . Photovoltaic device according to  claim 13 , wherein the semiconductor oxide layer comprises nanoparticles, preferably nanoparticles of TiO 2 .  
     
     
         15 . Method for preparing of a photovoltaic device having a solid conjugated semiconductor, preferably a device according to any of the  claims 1  to  14 , comprising evaporating at least one layer containing fluoride and/or acetate on at least one layer of the device.  
     
     
         16 . Method according to  claim 15 , additionally comprising the steps of: 
 (i) mixing a hole transport material with dopant; and    (ii) applying the mixture to a semiconductor oxide layer.    
     
     
         17 . Method according to  claim 15  or  16 , wherein the at least one layer is evaporated on top of a dye sensitized semiconductor oxide layer and/or on top of a layer of the hole transport material and/or on top of a transparent conductive electrode.  
     
     
         18 . Method according to any of  claim 15  to  17 , wherein the method further comprises at least one of the following steps: 
 providing a semiconductor oxide layer,  
 applying said mixture to said semiconductor oxide layer; and  
 connecting electrodes to said semiconductor oxide layer and to said mixture.  
 
     
     
         19 . Photovoltaic device according to any of the  claims 1  to  14 , wherein said photovoltaic device is a solar cell.  
     
     
         20 . Photovoltaic device cell according to  claim 19 , wherein the solar cell is a solid state hybrid solar cell.