Photocatalytic ceramic

Abstract

The present invention relates to a method for producing an antibacterial photocatalytic ceramic that comprises: —making available at least one amorphous metal; —making available a biomimetic material or a biomaterial based on calcium phosphate; —functionalizing said biomimetic material or said biomaterial based on calcium phosphate, with said at least one amorphous metal, obtaining a functionalized and oriented composite; —adding said functionalized composite to a ceramic mixture, and/or applying said functionalized composite on a ceramic semi-finished product, where ceramic semi-finished product means the ceramic material before baking; —applying said functionalized composite on a ceramic semi-finished product; —baking at a temperature between 600 and 1400° C., preferably between 900 and 1300° C., for a time that varies from 20 to 500 minutes, obtaining an antibacterial photocatalytic ceramic. The present invention further relates to a photocatalytic ceramic material that comprises a biomimetic material having a nanostructured hierarchical structure with macro and micro cavities, within which at least one photocatalytic material selected from metal oxides and/or sulphides in the crystalline form with a rutile-like structure is included, and tiles, sanitary ware and tableware comprising the same.

1 . A method for producing an antibacterial photocatalytic ceramic, the method comprising:
 making available at least one amorphous metal-containing material;   making available a biomimetic material or a biomaterial based on calcium phosphate;   functionalizing the biomimetic material or biomaterial based on calcium phosphate with the at least one amorphous metal-containing material, thereby obtaining a functionalized oriented composite, where oriented refers to having a regular crystallographic arrangement;   adding the functionalized oriented composite to a ceramic mixture, and/or applying the functionalized oriented composite on a ceramic semi-finished product, where the ceramic semi-finished product refers to a ceramic material before baking; and   baking at a temperature between 600 and 1400° C., for 20 to 500 minutes, thereby forming the antibacterial photocatalytic ceramic.   
     
     
         2 . The method of  claim 1 , wherein the at least one amorphous metal-containing material comprises a metal which is at least one selected from the group consisting of a transition metal and a post-transition metal. 
     
     
         3 . The method of claim  1 , wherein the at least one amorphous metal-containing material comprises a metal which is at least one selected from the group consisting of Titanium, Tin, Zinc, Zirconium, Cadmium, and Tungsten. 
     
     
         4 . The method of  claim 1 , wherein the amorphous metal-containing material is at least one selected from the group consisting of titanium(IV) oxysulphate, titanium tetrachloride, titanium tetraisopropoxide, titanium isopropoxide, titanium oxychloride, SnCl 2 , SnCl 4 , Sn(NO 3 ) 2 , SnSO 4 , Sn(CH 3 SO 3 ) 2 . 
     
     
         5 . The method of  claim 1 , wherein the biomimetic material or biomaterial based on calcium phosphate is at least one selected from the group consisting of brushite, monetite, hydroxyapatite (nHA), and (β/α) tricalcium phosphate (TCP); and the biomimetic material or biomaterial based on calcium phosphate is calcium-deficient on the surface. 
     
     
         6 . The method of  claim 1 , wherein the biomimetic material or biomaterial based on calcium phosphate is a biomimetic material which is nanocrystalline hydroxyapatite (nHA) obtained at a pH between 7 and 14 by neutralizing a suspension of a calcium source which is at least one selected from the group consisting of calcium hydroxide, calcium acetate, calcium chloride, and calcium nitrate drop by drop with phosphoric acid under vigorous stirring for 2-12 hours. 
     
     
         7 . The method of  claim 6 , wherein the nHA has a molar ratio of surface Ca/P in a range of 155 to 1.70. 
     
     
         8 . The method of  claim 1 , wherein the functionalizing is performed by adding the at least one amorphous metal-containing material dropwise to a solution of calcium phosphate in the form of brushite and/or monetite in a case of acid hydrolysis (pH 1-6), or in the form of nHA or (β/α) TCP in a case of basic hydrolysis (pH 7-14). 
     
     
         9 . The method of  claim 1 , wherein the functionalizing is performed with a doped titanium and/or a doped tin and the doped titanium and/or the doped tin is added dropwise in suspension with one or more dopant metal ions selected from the group consisting of Cu, Zn, Ag, Sr Al, Sb, W, Mn, Sn, V, Cr, Zr, Mo, and Pd. 
     
     
         10 . The method of  claim 9 , wherein said dopant metal ions are solvated. 
     
     
         11 . The method of  claim 1 , wherein the functionalized oriented composite is applied on a ceramic semi-finished product simultaneously with one or more glazing applications, or is mixed with engobe applied after the forming step, or is applied between one or more glazing applications and/or during a process of screen printing, and/or of salt glazing. 
     
     
         12 . An antibacterial photocatalytic ceramic material, comprising a ceramic material based on calcium phosphate which is at least one selected from the group consisting of a microcrystalline biomimetic material and a biomaterial, the ceramic material having a nanostructured hierarchical structure with macro and micro cavities within which is disposed a photocatalyst which is at least one selected from the group consisting of a metal oxide and a metal sulphide, the photocatalyst being in crystalline form with rutile-like structure, the rutile-like structure being arranged in a regular crystallographic arrangement. 
     
     
         13 . The antibacterial photocatalytic ceramic material of  claim 12 , wherein photocatalyst is at least one selected from the group consisting of TiO 2 , SnO 2 , ZnO, ZrO 2 , CdS and WO 3 . 
     
     
         14 . The antibacterial photocatalytic ceramic material of  claim 12 , wherein said at least one photocatalyst in crystalline form with rutile-like structure is TiO 2 , SnO 2  or mixtures thereof. 
     
     
         15 . (canceled) 
     
     
         16 . A ceramic article, comprising the photocatalytic ceramic material of  claim 12 , wherein the ceramic article is at least one selected from the group consisting of a tile, a sanitary ware, and a tableware.