(A) study for titanium-embedded layered double hydroxide water oxidation photocatalysts and nanocrystals of a metal-organic framework photocatalyst for carbon dioxide conversion = 티타늄이 삽입된 layered double hydroxide 물산화 광촉매 및 금속유기구조체 나노결정 이산화탄소 변환 광촉매에 관한 연구