<；P>；PROBLEM TO BE SOLVED: To provide a plasma electrode with photocatalytic activity that activates apatite having photocatalytic activity by plasma energy, and simply and effectively performs the decomposition and removal of harmful ingredients by the synergistic effects of the function of apatite having photocatalyst activity and the function of plasma energy, as well as a photocatalyst apatite activating method, and gas purification method and device using this apatite activating method. <；P>；SOLUTION: The plasma electrode related to this invention is characterized in that it has at least a discharger to generate atmospheric plasma by applying voltage, and in that this discharger has a plurality of projections at least at part of its discharge surface, and carries the apatite with photocatalyst activity between these projections on a level lower than the height of the projections. <；P>；COPYRIGHT: (C)2009,JPO&INPIT
