Effective Hydrogen Generation from the Hydrogen Sulfide Solution by using Stratified Type Photocatalyst.

Stratified type photocatalyst with the extremely higher photocatalytic activities can be synthesized by using the chemical reaction between the Na2S solution and Cd(OH)2 precursors. This type of photocatalyst has the specific morphology which constructed by the nano-sized and capsule like formed structure, and the metal concentration was gradually changed in its wall. The “charge gradient” was formed at the metal sulfide and oxide/hydroxide junction in the wall, which favored for the separation of the photo excited electron-hole pair. Consequently, stratified type photocatalyst shows the high catalytic activity than the usual nano CdS particles. By the addition of sulfur compound into the bio reactor contained the sulfur reducing bacteria, the H2S gas concentration can increased to about 1000 times enlarge than the usual condition. Therefore, we can conclude that the enhancement of the H2S gas evolved from the bio reactor was successfully achievement, and we don't need to afraid the shortage risk of H2S supply. These H2S gas concentration can enlarged to 80% by using A type zeorite. Especially, Ca-A type zeorite is considered as the suitable material. [ABSTRACT FROM AUTHOR]