Electrolysis Device

Abstract

An electrolysis device comprising a cell containing a solution, a pair of electrodes installed in the cell, and a voltage application device connected to the pair of electrodes. One electrode of the pair of electrodes is a small electrode, and another electrode of the pair of electroeds is a large electrode. An area of a liquid-contacting portion of the small electrode with the solution is smaller than an area of a liquid-contacting portion of the large electrode with the solution. In a state in which the solution is contained in the cell, only the solution is present between the liquid-contacting portion of the small electrode and a liquid surface of the solution vertically above the liquid-contacting portion of the small electrode.

What is claimed is: 
     
         1 . An electrolysis device comprising:
 a cell containing a solution;   a pair of electrodes installed in the cell; and   a voltage application device connected to the pair of electrodes,   wherein one electrode of the pair of electrodes is a small electrode, and another electrode of the pair of electrodes is a large electrode,   wherein a liquid-contacting portion of the small electrode, which is a portion of the small electrode that makes contact with the solution, has a smaller area than an area of a liquid-contacting portion of the large electrode, which is a portion of the large electrode that makes contact with the solution, and   wherein only the solution is present between the liquid-contacting portion of the small electrode and a liquid surface of the solution vertically above the liquid-contacting portion of the small electrode in a state in which the solution is contained in the cell.   
     
     
         2 . The electrolysis device of  claim 1 , wherein:
 a part of the small electrode is covered by an insulator;   a portion of the small electrode exposed from the insulator is the liquid-contacting portion of the small electrode; and   the small electrode is installed so that an end edge of the insulator at the liquid-contacting portion is perpendicular to the liquid surface of the solution or faces upward.   
     
     
         3 . The electrolysis device of  claim 1 , wherein the large electrode is installed at a position other than vertically above the liquid-contacting portion of the small electrode. 
     
     
         4 . The electrolysis device of  claim 1 , further comprising:
 a light-transmissive portion that is provided in an outer wall of the cell, in a vicinity of a tip end of the small electrode, and that is transmissive to light from the cell to outside; and   a light receiver that is disposed outside the light-transmissive portion and receives light transmitted through the light-transmissive portion,   wherein a charge carrying detection substance is included in the solution contained in the cell,   wherein the detection substance is concentrated in the cell at the small electrode by applying a voltage from the voltage application device across the pair of electrodes,   wherein plasma is generated at the small electrode by applying a higher voltage from the voltage application device across the pair of electrodes than the voltage when concentrating the detection substance, and   wherein luminescence of the detection substance generated by the plasma is detectable by the light receiver through the light-transmissive portion.   
     
     
         5 . The electrolysis device of  claim 4 , wherein:
 the voltage application device is capable of switching a direction of current when applying voltage; and   a direction of current when generating plasma is an opposite direction to a direction of current when concentrating the detection substance.   
     
     
         6 . The electrolysis device of  claim 1 , wherein the area of the liquid-contacting portion of the small electrode is from 0.01 mm 2  to 6 mm 2 .