Semiconductor structures for fuel generation

Abstract

This disclosure relates to photovoltaic and photo-electrosynthetic cells, devices, methods of making and using the same.

What is claimed is: 
     
         1 . A method of making an elongated structure, comprising:
 (a) fabricating a first semiconductive structures on a Si substrate comprising
 (i) forming a templated oxide layer on the substrate, wherein the template for the templated oxide layer comprises openings in the oxide layer for the formation of a first semiconductive structure; and 
 (ii) growing a set of first semiconductive structures on the substrate, wherein the first semiconductive structure growth is supported by a catalyst deposited in the openings in the oxide layer; 
   (b) coating the fabricated first semiconductive structures in an oppositely doped semiconductive material layer to generate an emitter layer;   (c) coating the emitter layer with an transparent low resistance layer; and   (d) radially and epitaxially applying a second semiconductive material on the transparent low resistance layer, wherein the second semiconductive material has the same or wider band-gap as the first semiconductive material.   
     
     
         2 . The method of  claim 1 , wherein the low resistance layer comprises a semiconductive material. 
     
     
         3 . The method of  claim 1 , wherein the low resistance layer comprises a transparent conductive oxide. 
     
     
         4 . The method of  claim 3 , wherein the transparent conductive oxide is selected from the group consisting of cadmium tin oxide (CTO), indium tin oxide (ITO), fluorine-doped tin oxide (SnO:F or FTC)), indium-doped cadmium-oxide, cadmium stannate (Cd 2 SnO 4  or CTO), doped zinc oxide (ZnO), such as aluminum-doped zinc-oxide (ZnO:Al or AZO), indium-zinc oxide (IZO), zinc tin oxide (ZnSnO x ), and combinations thereof. 
     
     
         5 . The method of  claim 1 , wherein the elongated structure is substantially embedded in a wax, glass or polymer. 
     
     
         6 . The method of  claim 5 , wherein the embedded elongated structure are mechanically removed from the Si substrate. 
     
     
         7 . The method of  claim 1 , further comprising applying a hydrogen evolving and/or oxygen evolving catalyst to the elongated structure. 
     
     
         8 . The method according to  claim 7 , wherein the catalyst is selected from the group consisting of Pt, Co, Cu, Fe, MoS x  where x is nominally 2, or a sub or super-stoichiometric, Ni, CoMo, CoW, FeMo, NiCo, NiFe, NiFeC, NiFeS, NiMnS, NiMo, NiMoP, NiSn, NiW, NiZn, NiZnP, CoNiFe, NiCoPMo, NiMoCo, NiMoCu, NiMoFe, NiMoW, NiSiMo, NiSiW, NiWPCu, IrO x  where x is nominally 2, or sub or super-stoichiometric, Pt, Co, Co/(PO 4 ) 3− , Co/(BO 3 ) 3− , CoP, Cu, Fe, Mn, Ni, Ni/(BO 3 ) 3− , NiP, Pb, CoFe, CoPSc 2 O 3 , FeMn, NiCo, NiCr, NiCu, NiFe, NiLa, NiLa, NiPSc 2 O 3 , NiSn, NiZn and NiMoFe. 
     
     
         9 . A device or photocell comprising:
 a substrate;   an ordered array of elongate semiconductor structures comprising at least 2 different semiconductive materials axially and radially integrated, wherein the elongate semiconductor structures have length dimensions defined by adjacent ends in electrical contact with at least portions of the substrate and distal ends not in contact with the substrate and have radial dimensions generally normal to the length dimensions and the radial dimensions are less than the length dimensions;   a transparent ohmic layer separating the at least 2 different semiconductive materials; and   wherein the device absorbs received light and converts it into electricity or chemical energy.   
     
     
         10 . The device or photocell of  claim 9 , wherein the elongated semiconductor structures comprise wires. 
     
     
         11 . The device or photocell of  claim 10 , wherein the elongate semiconductor structures are embedded in a matrix. 
     
     
         12 . The device or photocell of  claim 11 , wherein the matrix is a glass, polymer or wax. 
     
     
         13 . The device or photocell of  claim 11 , wherein the elongate semiconductor structures are partially or fully embedded in a matrix.