Element with an electrically adjustable surface emissivity for infrared radiation

Abstract

An element having an electrically adjustable thermal emissivity for infrared radiation has the following layer structure: forward IR-transparent substrate; function layer whose reflectivity for IR radiation can be changed by the embedding of hydrogen; anhydrous IR-absorptive proton conductor layer;hydrogen storage layer; and electrode layer. The surface whose emissivity is to be controlled, is covered with one or more elements according to the invention, which are electrically connected with one another and can be wired in the form of strings or arrays.

What is claimed is:  
     
         1 . An element with an electrically adjustable surface emissivity for infrared radiation, comprising: 
 a forward IR-transparent substrate;    a function layer whose reflectivity for IR radiation can be changed by embedding of hydrogen;    an anhydrous IR-absorptive proton conductor layer;    a hydrogen storage layer; and    an electrode layer.    
     
     
         2 . The element according to    claim 1   , wherein said infrared radiation has a wavelength within a range of approximately 1 μm to approximately 30 μm.  
     
     
         3 . The element according to    claim 1   , wherein the electrode layer is applied to a rearward substrate.  
     
     
         4 . The element according to    claim 1   , further comprising an oxidation protection layer disposed between the function layer and the proton conductor layer.  
     
     
         5 . The element according to    claim 4   , wherein the oxidation protection layer is made of a material selected from the group consisting of Pd, Pt, NbO 3  or V 2 O 5 .  
     
     
         6 . The element according to    claim 4   , wherein the electrode layer is made of an electrically conductive material.  
     
     
         7 . The element according to    claim 6   , wherein said electrically conductive material is selected from the group consisting of Au, Pt, Al, Pd, Cu, ITO.  
     
     
         8 . The element according to    claim 1   , wherein the hydrogen storage layer is made of a material selected from the group consisting of WO 3 , Y, NiO, LaNi 5 , FeTi and Pd.  
     
     
         9 . The element according to    claim 1   , wherein the proton conductor layer contains mobile proton carriers.  
     
     
         10 . The element according to    claim 9   , wherein said mobile proton carriers comprise one of imidazole and pyrazole.  
     
     
         11 . The element according to    claim 9   , wherein the proton conductor layer is made of a material selected from the group consisting of sulfonated polyetherketone, polyetheretherketone and polyaryletherketone.  
     
     
         12 . The element according to    claim 1   , wherein the function layer is made of a material which forms at least two different hydrides, whose IR-reflectivities are different.  
     
     
         13 . The element according to    claim 12   , wherein the function layer is made of a hydride of a rare-earth metal.  
     
     
         14 . The element according to    claim 1   , wherein the rare earth metal is one of scandium, yttrium, lanthanum, cerium, praseodymium and neodymium.  
     
     
         15 . The element according to    claim 14   , wherein the function layer is made of an alloy of at least two of said metals.  
     
     
         16 . The element according to    claim 1   , wherein the forward substrate is made of a material selected from the group consisting of silicon or germanium.  
     
     
         17 . The element according to    claim 1   , wherein the forward substrate carries one of an antireflection layer and an antireflection layer system which has an antireflection effect in the IR wavelength range.  
     
     
         18 . Use of an element according to    claim 1   , for regulating one of thermal economy of spacecraft by the controlled radiation of heat in space, and the air-conditioning in buildings or vehicles.