本論文以離子交換法合成CuFeO¬2光觸媒，並藉由Ｘ-ray光繞射分析、穿透式電子顯微鏡以及可見光-近紅外光漫反射光譜，進行晶格結構、晶粒大小、能帶間隙以及光吸收特性之鑑定，而探討材料特性對CuFeO¬2光觸媒活性之影響。
研究結果發現，以EDFS•3H2O作為前驅物，在1 L/min流通空氣下，經530 ℃之兩次熱處理後，可成功地合成高結晶性之α-NaFeO2，其晶粒尺寸為5~10 nm。在氧氣充足之環境下，獲得高結晶性之α-NaFeO2產物，可歸因於β-NaFeO2之生成被有效地抑制。
以高結晶性之α-NaFeO2作為前驅物，在500 ℃之熔融CuCl中，經Na＋-Cu＋離子交換，可成功地合成純相之CuFeO2，其顆粒尺寸為10~20 nm。當離子交換程序之溫度提高時，CuFeO2晶粒沿著垂直c軸方向有較顯著之成長，則使CuFeO2產物裸露出較多與c軸正交之晶面，有利於CuFeO2吸收700 ~900 nm 之近紅外光。
本研究合成之CuFeO2產物受光激發後，CuFeO2顆粒內部之晶界，快速地捕捉光生電子與光生電洞，而形成再結合之場所，因此水分子則無法成功地在CuFeO2表面被還原成氫氣。

Nanocrystalline CuFeO2 has been synthesized successfully by ion-exchanging molten CuCl with layer-structured -NaFeO2. Crystal structure and domain size of CuFeO2 were characterized by XRD and TEM. Optical properties of CuFeO2 were determined by visible-infrared spectrum as well. In addition, Z-scheme photocatalytic water splitting without electron mediator carried out in a fluidized-bed photocatalyst reactor with as-synthesized CuFeO2 and Bi20TiO32 powder is proposed and measured in the present work.
First, nanocrystalline -NaFeO2 was synthesized successfully by thermal decomposition of EDFS under the air flow of 1 L/min and calcinations at 530 ℃ twice. The grain size of -NaFeO2 is measured about 5 ~ 10 nm by TEM. High crystallinity of -NaFeO2 results from suppressing the formation of -NaFeO2 under sufficient O2 condition.
Next, nanocrystalline CuFeO2 was synthesized successfully by ion-exchange method and domain size of CuFeO2 is about 5 ~ 10 nm determined by TEM. Domain boundaries of CuFeO2 result from sintering of grains in molten CuCl. Crystal growth of CuFeO2 is more significant in direction of a axis and b axis when operating temperature of molten CuCl increases. Near-IR absorbance of CuFeO2 increases slightly with increasing dimension of the plane in c axis.
The H2 production from the system could not be successfully detected. One reason could be attributed to the serious recombination of photon-generated electrons and holes at the grain boundaries of CuFeO2.

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