Biotemplated perovskite nanomaterials

Abstract

A biotemplated nanomaterial can include a crystalline perovskite.

What is claimed is: 
     
         1 . A method of making a nanomaterial comprising forming a perovskite in the presence of a biotemplate having affinity for a metal ion. 
     
     
         2 . The method of  claim 1 , wherein the biotemplate includes a virus particle. 
     
     
         3 . The method of  claim 2 , wherein the virus particle is an M13 bacteriophage. 
     
     
         4 . The method of  claim 1 , wherein forming the perovskite includes forming an aqueous mixture including the biotemplate, a first inorganic ion, and a second inorganic ion. 
     
     
         5 . The method of  claim 4 , further comprising forming an ion source including the first inorganic ion and the second inorganic ion before forming the aqueous mixture. 
     
     
         6 . The method of  claim 4 , further comprising adjusting the pH of the aqueous mixture and incubating the aqueous mixture for a predetermined time at a predetermined temperature. 
     
     
         7 . The method of  claim 4 , further comprising calcining the reaction products after incubating the aqueous mixture. 
     
     
         8 . The method of  claim 1 , wherein the perovskite has the formula (I):
   A x A′ 1-x B y B′ 1-y O 3±δ   (I)
   wherein   each of A and A′, independently, is a rare earth, alkaline earth metal, or alkali metal;   each of B and B′, independently, is a transition metal;   x is in the range of 0 to 1;   y is in the range of 0 to 1; and   δ is in the range of 0 to 1.   
     
     
         9 . The method of  claim 8 , wherein A and A′, independently, are selected from the group consisting of Mg, Ca, Sr, Ba, Pb, and Bi; and B and B′, independently, are selected from the group consisting of Ti, Zr, V, Nb, Mn, Fe, Ru, Co, Rh, Ni, Pd, Pt, Al, and Mg. 
     
     
         10 . The method of  claim 8 , wherein the perovskite is a strontium titanate. 
     
     
         11 . The method of  claim 8 , wherein the perovskite is a bismuth ferrite. 
     
     
         12 . The method of  claim 1 , wherein the perovskite is a tantalum oxide, tantalum oxynitride or tantalum nitride. 
     
     
         13 . The method of  claim 12 , wherein the perovskite is sodium tantalate, zirconium oxide/tantalum oxynitride, zirconium tantalum oxynitride, tantalum oxynitride, tantalum nitride, or zirconium tantalum nitride. 
     
     
         14 . A biotemplated nanomaterial comprising interconnected crystalline perovskite nanoparticles. 
     
     
         15 . The biotemplated nanomaterial of  claim 14 , wherein the nanomaterial is elongated in shape. 
     
     
         16 . The biotemplated nanomaterial of  claim 15 , wherein the nanoparticles have a particle size of no greater than about 50 nm. 
     
     
         17 . The biotemplated nanomaterial of  claim 16 , wherein the nanomaterial has a diameter of no greater than about 100 nm. 
     
     
         18 . The biotemplated nanomaterial of  claim 17 , wherein the nanoparticles have a particle size of no greater than about 10 nm, and the nanomaterial has a diameter of no greater than about 20 nm. 
     
     
         19 . The biotemplated nanomaterial of  claim 16 , wherein the nanomaterial has a length of greater than 500 nm. 
     
     
         20 . The biotemplated nanomaterial of  claim 14 , wherein the nanomaterial includes strontium titanate. 
     
     
         21 . The biotemplated nanomaterial of  claim 14 , wherein the nanomaterial includes bismuth ferrite. 
     
     
         22 . The biotemplated nanomaterial of  claim 14 , wherein the perovskite is a tantalum oxide, tantalum oxynitride or tantalum nitride. 
     
     
         23 . The biotemplated nanomaterial of  claim 23 , wherein the perovskite is sodium tantalate, zirconium oxide/tantalum oxynitride, zirconium tantalum oxynitride, tantalum oxynitride, tantalum nitride, or zirconium tantalum nitride. 
     
     
         24 . A photocatalyst comprising the biotemplated nanomaterial of  claim 14 . 
     
     
         25 . A photovoltaic device comprising the biotemplated nanomaterial of  claim 14 . 
     
     
         26 . The method of  claim 1 , further comprising exposing the perovskite to ammonia gas. 
     
     
         27 . The method of  claim 26 , wherein the perovskite is heated to at least 600° C. 
     
     
         28 . The method of  claim 26 , wherein the perovskite is heated to at least 650° C. 
     
     
         29 . The method of  claim 26 , wherein the post-treated nanomaterials are solar active.