Organic spintronic devices and methods for making the same

Abstract

An organic spintronic photovoltaic device having an organic electron active layer functionally associated with a pair of electrodes. The organic electron active layer can include a spin active molecular radical distributed in the active layer which increases spin-lattice relaxation rates within the active layer. The increased spin lattice relaxation rate can also influence the efficiency of OLED and charge mobility in FET device.

What is claimed is: 
     
         1 . An organic spintronic device, comprising:
 a) an organic electron active layer which is either a bulk heterojunction including a donor material blended with an acceptor material, or a bi-layer including an organic donor layer adjacent to an organic acceptor layer, said organic electron active layer including a spin active molecular radical distributed in the organic electron active layer which increases spin-lattice relaxation rates within the active layer; and   b) a pair of electrodes functionally associated with the organic electron active layer to complete a circuit which transfers electrons via the organic electron active layer.   
     
     
         2 . The device of  claim 1 , wherein the spin active molecular radical distributed in the organic electron active layer induces a spin flip in at least one of a spin ½ electron and a hole to result in a spin triplet state having an increased exciton diffusion length 
     
     
         3 . The device of  claim 1 , wherein the organic spintronic device is an organic photovoltaic. 
     
     
         4 . The device of  claim 1 , wherein the organic electron active layer is the bulk heterojunction including the donor material blended with the acceptor material. 
     
     
         5 . The device of  claim 1 , wherein the active layer is a bi-layer including the organic donor layer adjacent to the organic acceptor layer. 
     
     
         6 . The device of  claim 1 , wherein the organic electron active layer is comprised of P3HT/PCBM. 
     
     
         7 . The device of  claim 1 , wherein the spin active molecular radical is a ½ spin molecular radical. 
     
     
         8 . The device of  claim 1 , wherein the spin active molecular radical is selected from the group consisting of: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
         9 . The device of  claim 8 , wherein the spin active molecular radical is TEMPO or TOPO. 
     
     
         10 . The device of  claim 1 , wherein the spin active molecular radical is present from 0.1 wt % to about 10 wt % of the organic electron active layer. 
     
     
         11 . The device of  claim 10 , wherein the spin active molecular radical is TEMPO and is present at about 5 wt % of the organic electron active layer. 
     
     
         12 . The device of  claim 1 , wherein the organic electron active layer comprises a donor polymer and an acceptor molecule. 
     
     
         13 . The device of  claim 12 , wherein the donor polymer includes 2-methoxy-5-(2′-ethylhexyloxy) phenylene vinylene polymer (MEHPPV), 1,4-bis[(4-styryl)styryl]-2-methoxy-5-(2′-ethylhexoxy)benzene polymer, poly(2-methoxy,5-(3′,7′-dimethyloctyloxy)-1,4-phenylenevinylene (MDMOPPV), poly(2,5-(2-ethylhexyloxy)-1,4-phenylenevinylene) (BEHPPV), or regio regular poly(3-hexylthiophene). 
     
     
         14 . The device of  claim 12 , wherein the acceptor molecule includes fullerene C60, PCBM (soluble C60), TiO 2 , modified fullerenes, C70, C84, soluble modified fullerence, or Di-PCBM. 
     
     
         15 . The device of  claim 1 , wherein the organic spintronic device exhibits an increased current of at least 10% over a device having the same structure and components as the organic spintronic device without the spin active molecular radical. 
     
     
         16 . The device of  claim 15 , wherein the increased current is from 20% to 50%. 
     
     
         17 . The device of  claim 1 , wherein the pair of electrodes include an indium tin oxide anode. 
     
     
         18 . The device of  claim 1 , wherein the pair of electrodes include a cathode which further includes a conductive metal layer and an electron transport layer, said electron transport layer located between the organic electron active layer and the conductive metal layer. 
     
     
         19 . The device of  claim 1 , wherein the acceptor molecule comprises a fullerene and the spin active molecular radical is galvinoxyl (2,6-Di-tert-butyl-α-(3,5-di-tert-butyl-4-oxo-2,5-cyclohexadien-1-ylidene)-ptolyloxy)