Fusing porphyrins with polycyclic aromatic hydrocarbons and heterocycles for optoelectronic applications

Abstract

A compound that can be used as a donor material in organic photovoltaic devices comprising a non-activated porphyrin fused with one or more non-activated polycyclic aromatic rings or one or more non-activated heterocyclic rings can be obtained by a thermal fusion process. By heating the reaction mixture of non-activated porphyrins with non-activated polycyclic aromatic rings or heterocyclic rings to a fusion temperature and holding for a predetermined time, fusion of one or more polycyclic rings or heterocyclic rings to the non-activated porphyrin core in meso,β fashion is achieved resulting in hybrid structures containing a distorted porphyrin ring with annulated aromatic rings. The porphyrin core can be olygoporphyrins.

We claim: 
     
         1 . A compound comprising a non-activated porphyrin fused with one or more non-activated heterocyclic rings, said compound having a formula selected from the group consisting of: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         wherein M is two hydrogen atoms or any element selected from the group consisting of Mg, Ca, Sr, Ba, Sc, Y, La, Ce, Ti, Nb, Ta, Cr, Mo, W, Mn, Tc, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Hg, Al, Ga, In, Tl, Si, Ge, Sn, Pb, P, As, Sb, Bi, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Th, and U; 
         wherein R 1 -R 14  are independently selected from the group consisting of hydrogen, alkyl, fluoroalkyl, hydroxyl, alkoxy, halo (Cl, Br, I), chalcogens (S, Se, Te), mercapto group, amino, cyano, alkenyl, alkynyl, and aryl; 
         wherein X is O, S, Se, Te, N, P, As, Si, Ge, or B; and 
         each dotted arc is all possible combinations of fused non-activated rings, both aromatic and unsaturated or combinations of both aromatic and unsaturated rings including four, five, six, seven, eight, or nine-membered rings, and all possible combinations of fused heterocyclic rings with one or more heteroatoms, including all possible combinations of all heteroatoms in all possible arrangements. 
       
     
     
         2 . The compound of  claim 1 , wherein the porphyrin and at least one of the heterocyclic rings are fused in (meso,β) mode. 
     
     
         3 . The compound of  claim 1 , wherein the porphyrin and at least one of the heterocyclic rings are fused in (β,meso, β) mode. 
     
     
         4 . The compound of  claim 1 , wherein the one or more non-activated heterocyclic rings are selected from the group consisting of: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         wherein the wave-line represents the fusion position of the heterocyclic rings to the porphyrin; and 
         wherein the dot represents the point where the heterocyclic rings are connected to the meso position of the porphyrin. 
       
     
     
         5 . A photosensitive device comprising:
 a first electrode;   a second electrode; and   a photoactive region provided between the first electrode and the second electrode, wherein the photoactive region comprising:
 a donor material; and 
 an acceptor material, wherein donor material is a compound comprising a non-activated porphyrin fused with one or more non-activated heterocyclic rings, said compound having a formula selected from the group consisting of: 
   
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         wherein M is two hydrogen atoms or any element selected from the group consisting of Mg, Ca, Sr, Ba, Sc, Y, La, Ce, Ti, Nb, Ta, Cr, Mo, W, Mn, Tc, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Hg, Al, Ga, In, Tl, Si, Ge, Sn, Pb, P, As, Sb, Bi, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Th, and U; 
         wherein R 1 -R 14  are independently selected from the group consisting of electron donor and acceptor groups, such as hydrogen, alkyl, fluoroalkyl, hydroxyl, alkoxy, halo (Cl, Br, I), chalcogens (S, Se, Te), mercapto group, amino, cyano, alkenyl, alkynyl, and aryl; 
         wherein X is O, S, Se, Te, N, P, As, Si, Ge, or B; and 
         each dotted arc is all possible combinations of fused rings, both aromatic and unsaturated or combinations of both aromatic and unsaturated rings including four, five, six, seven, eight, or nine-membered rings, and all possible combinations of fused heterocyclic rings with one or more heteroatoms, including all possible combinations of all heteroatoms in all possible arrangements. 
       
     
     
         6 . The device of  claim 5 , wherein the porphyrin and at least one of the non-activated heterocyclic rings are fused in (meso,β) mode. 
     
     
         7 . The device of  claim 5 , wherein the porphyrin and at least one of the non-activated heterocyclic rings are fused in (β,meso, β) mode. 
     
     
         8 . The device of  claim 5 , wherein the one or more non-activated heterocyclic rings are selected from the group consisting of: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         wherein the wave-line represents the fusion position of the heterocyclic rings to the porphyrin; and 
         wherein the dot represents the point where the heterocyclic rings are connected to the meso position of the porphyrin. 
       
     
     
         9 . A process for fusing one or more non-activated polycyclic rings to a non-activated porphyrin core comprising:
 heating a quantity of precursor porphyrins to a fusion temperature in an inert gas environment, wherein the fusion temperature is associated with the precursor porphyrins;   holding the precursor porphyrins at the fusion temperature for a predefined period of time until the precursor porphyrins melt and form a mixture of fused porphyrins;   cooling the mixture of fused porphyrins to room temperature; and   separating the mixture of fused porphyrins into various fused porphyrin compounds according to  claim 1 .   
     
     
         10 . The process according to  claim 9 , wherein the fusion temperature is above melting point of the precursor porphyrins. 
     
     
         11 . The process according to  claim 9 , wherein separating the mixture of fused porphyrins comprises column chromatography. 
     
     
         12 . The process according to  claim 9 , further comprising purification of the separated fused porphyrin compounds through recrystallization of the separated fused porphyrin compounds. 
     
     
         13 . A method for fabricating a photosensitive device comprising:
 depositing a first electrode layer on a substrate;   forming a photoactive region over the first electrode, wherein the forming comprises:
 (a)(1) depositing a layer of organic donor material over the first electrode and forming an interim structure, wherein the organic donor material comprising a precursor porphyrin material, 
 (a)(2) thermally fusing the precursor porphyrin material by heating the interim structure to a fusion temperature in an inert gas environment and holding the interim structure at the fusion temperature for a predefined period of time until the precursor porphyrin material melts and forms a layer of mixture of fused prophyrins, wherein the fusion temperature is associated with the precursor porphyrin material, and 
 (a)(3) depositing a layer of an organic acceptor material over the layer of organic donor material, whereby the organic donor material layer and the organic acceptor material layer form a photoactive region; or 
 (b)(1) depositing a layer of a mixture of an organic donor material and an organic acceptor material over the first electrode and forming an interim structure, wherein the organic donor material comprises a precursor porphyrin material, and 
   (b)(1) thermally fusing the precursor porphyrin material by heating the interim structure to a fusion temperature in an inert gas environment and holding the interim structure at the fusion temperature for a predefined period of time until the precursor porphyrin material melts and forms fused porphyrins, wherein the fusion temperature is associated with the precursor porphyrin material, whereby the fused porphyrins and the organic acceptor material form the organic photoactive region; and   depositing a second electrode layer over the organic acceptor material layer.