Enhanced photo-catalytic cells

Abstract

A photo-catalytic cell may produce bactericidal molecules in air by passing air across catalyst coated targets. Ultraviolet (UV) energy may be emitted from a source. A first portion of the UV energy from the source may be applied directly onto the targets. A second portion of the UV energy from the source may be reflected onto the targets.

1 . An apparatus for ionizing air, the apparatus comprising:
 a first target including:
 an inner face arranged to receive ultra-violet (“UV”) energy from a UV emitter, 
 an outer face, 
 a plurality of passages between the inner face and the outer face, and 
 a photo-catalytic coating on the plurality of passages; 
   a first reflector configured to reflect UV energy from the UV emitter towards the photo-catalytic coating of the first target, wherein the first reflector is a specular UV reflector; and   wherein the first target is configured to:
 receive, through the inner face and at the photo-catalytic coating, UV energy from the UV emitter and the first reflector, 
 generate ions in response to the received UV energy, 
 pass an airflow from the inner face and through the plurality of passages to carry the ions away from the outer face. 
   
     
     
         2 . The apparatus of  claim 1 , wherein a reflecting surface of the first reflector is electrically conductive. 
     
     
         3 . The apparatus of  claim 1 , wherein the first reflector comprises micro-polished stainless steel. 
     
     
         4 . The apparatus of  claim 1 , wherein the first reflector comprises a chromium-plated material. 
     
     
         5 . The apparatus of  claim 1 , wherein the first reflector comprises a material that does not readily oxidize. 
     
     
         6 . The apparatus of  claim 1 , wherein the first reflector comprises a material having a UV reflectivity of about 90% or greater at UV wavelengths of 185 nm and 254 nm. 
     
     
         7 . The apparatus of  claim 1 , wherein the first target comprises a honeycomb matrix. 
     
     
         8 . The apparatus of  claim 1 , further comprising:
 a second target opposite the first target, wherein the second target includes:
 an inner face arranged to receive ultra-violet (“UV”) energy from a UV emitter, 
 an outer face, 
 a plurality of passages between the inner face and the outer face, and 
 a photo-catalytic coating on the plurality of passages; 
   wherein the first reflector is further configured to reflect UV energy from the UV emitter towards the photo-catalytic coating of the second target; and   wherein the second target is configured to:
 receive, through the inner face and at the photo-catalytic coating, 
 UV energy from the UV emitter and the first reflector, 
 generate ions in response to the received UV energy, 
 pass an airflow from the outer face and through the plurality of passages to carry the ions away from the inner face. 
   
     
     
         9 . The apparatus of  claim 8 , wherein the second target comprises a honeycomb matrix. 
     
     
         10 . The apparatus of  claim 1 , further comprising a seventh reflector on the inner face of the first target and configured to reflect UV energy that is emitted from the UV emitter in a direction that is almost orthogonal to the inner surface of the first target, wherein the seventh reflector is a specular UV reflector. 
     
     
         11 . An apparatus for ionizing air, the apparatus comprising:
 a chamber including:
 a first target comprising: 
 a plurality of passages between an interior area of the chamber and an exterior area, and 
 a photo-catalytic coating on the plurality of passages; 
   a first reflector configured to reflect UV energy from a UV emitter towards the photo-catalytic coating of the first target, wherein the first reflector is a specular UV reflector; and   wherein the photo-catalytic coating is arranged to receive UV energy directly from the UV emitter and UV energy reflected from the first reflector.   
     
     
         12 . The apparatus of  claim 11 , further comprising at least one corner reflector arranged in an interior corner of the chamber, wherein the at least one corner reflector is a specular UV reflector. 
     
     
         13 . The apparatus of  claim 11 , wherein the chamber further includes:
 a second target opposite the first target, wherein the second target includes:
 a plurality of passages between the interior area of the chamber and the exterior area, and 
 a photo-catalytic coating on the plurality of passages; 
   wherein the first reflector is further configured to reflect UV energy from the UV emitter towards the photo-catalytic coating of the second target; and   wherein the photo-catalytic coating is arranged to receive UV energy directly from the UV emitter and UV energy reflected from the first reflector.   
     
     
         14 . The apparatus of  claim 13 , further comprising a second reflector opposite the first reflector and configured to reflect UV energy from the UV emitter towards the photo-catalytic coating of the first target and the photo-catalytic coating of the second target, and
 wherein the second reflector is a specular UV reflector.   
     
     
         15 . The apparatus of  claim 14 , further comprising:
 a third reflector located at a corner between the first target and the first reflector;   a fourth reflector located at a corner between the second target and the first reflector;   a fifth reflector located at a corner between the first target and the second reflector; and   a sixth reflector located at a corner between the first target and the second reflector.   
     
     
         16 . The apparatus of  claim 11 , further comprising a seventh reflector on the first target and facing the interior area of the chamber,
 wherein the seventh reflector configured to reflect UV energy that is emitted from the UV emitter in a direction that is almost orthogonal to the first target, and   wherein the seventh reflector is a specular UV reflector.   
     
     
         17 . The apparatus of  claim 11 , wherein a reflecting surface of the first reflector is electrically conductive. 
     
     
         18 . The apparatus of  claim 11 , wherein the first target comprises a honeycomb matrix. 
     
     
         19 . The apparatus of  claim 11 , wherein the first reflector comprises a material having a UV reflectivity of about 90% or greater at UV wavelengths of 185 nm and 254 nm. 
     
     
         20 . A method for ionizing air, the method comprising:
 emitting, by an ultra-violet (“UV”) emitter, UV energy towards a first reflector and a first target;   reflecting, by a first reflector, UV energy towards the first target, wherein the first reflector is a specular UV reflector;   receiving, at a plurality of passages through the first target, UV energy directly from the UV emitter and UV energy reflected from the first reflector;   responsively generating ions at a photo-catalytic coating on the plurality of passages of the first target; and   passing an airflow through the plurality of passages of the first target to carry the ions away from the first target.   
     
     
         21 . The method of  claim 20 , wherein the step of responsively generating ions further comprises responsively generating more ions at the photo-catalytic coating in response to receiving UV energy from the first reflector than in response to receiving UV energy directly from the UV emitter. 
     
     
         22 . The method of  claim 20 , further comprising:
 emitting, by the UV emitter, UV energy towards the first reflector and a second target;   reflecting, by the first reflector, UV energy towards the second target;   receiving, at a plurality of passages through the second target, UV energy from the UV emitter and from the first reflector;   responsively generating ions at a photo-catalytic coating on the plurality of passages of the second target; and   passing an airflow through the plurality of passages of the second target to carry the ions away from the second target and towards the first target.   
     
     
         23 . The method of  claim 20 , wherein the first reflector comprises a material having a UV reflectivity of about 90% or greater at UV wavelengths of 185 nm and 254 nm. 
     
     
         24 . An apparatus for ionizing air, the apparatus comprising:
 a first reflector configured to reflect ultra-violet (“UV”) energy from a UV emitter, wherein the first reflector is a specular UV reflector; and   a plurality of passages having a photo-catalytic coating, wherein the plurality of passages is arranged to:
 receive direct UV energy directly from the UV emitter, 
 receive specularly reflected UV energy reflected from the first reflector, 
 generate a first number of ions at the photo-catalytic coating in response to receiving the specularly reflected UV energy, and 
 generating a second number of ions at the photo-catalytic coating in response to receiving the direct UV energy, 
   wherein the first number of ions is greater than the second number of ions.   
     
     
         25 . The apparatus of  claim 24 , wherein the plurality of passages is further arranged to:
 receive the direct UV energy at a first incident angle,   receive the specularly reflected UV energy at a second incident angle, and   wherein the second incident angle is greater than the first incident angle.   
     
     
         26 . An apparatus for ionizing air, the apparatus comprising:
 a first reflector configured to reflect ultra-violet (“UV”) energy from a UV emitter, wherein the first reflector is a specular UV reflector; and   a first target having a photo-catalytic coating arranged to:
 receive direct UV energy directly from the UV emitter, 
 receive specularly reflected UV energy reflected from the first reflector, 
 responsively generate ions in response to the direct UV energy and the specularly reflected UV energy, and 
 emit the ions into an airflow directed to deliver the ions into an external environment. 
   
     
     
         27 . An apparatus for ionizing air, the apparatus comprising:
 a first reflector configured to reflect ultra-violet (“UV”) energy from a UV emitter, wherein the first reflector is a specular UV reflector; and   a first target having a photo-catalytic coating arranged to:
 receive direct UV energy directly from the UV emitter at a first range of incident angles, and 
 receive specularly reflected UV energy from the first reflector at a second range of incident angles, 
 wherein the second range of incident angles is larger than the first range of incident angles. 
   
     
     
         28 . The apparatus of  claim 27 , wherein the largest angle in the first range of incident angles is less than the smallest angle in the second range of incident angles. 
     
     
         29 . The apparatus of  claim 27 , wherein the photo-catalytic coating is further arranged to:
 responsively generate a first number of ions in response to the direct UV energy, and   responsively generate a second number of ions in response to the specularly reflected UV energy,   wherein the second number of ions is greater than the first number of ions.