CuFeO¬2光觸媒能帶間隙為1.34 eV，其可利用光源幾乎涵蓋整個太陽光譜，被認為是極具潛力做為太陽能轉換的觸媒。文獻中指出CuFeO2在高溫下之合成，顯著地受煅燒氣氛所影響，不易獲得純相之CuFeO2產物。本研究先以Na[EDTA-Fe]．3H2O作為前驅物，經熱分解而合成α-NaFeO2；再將已製備之α-NaFeO2，在相對低溫下，進行Na+-Cu+離子交換反應，藉此合成具有高比表面積之CuFeO2光觸媒。並藉由Ｘ-ray光繞射分析、穿透式電子顯微鏡、可見光-近紅外光漫反射及光激發螢光光譜射光譜，進行晶格結構、晶粒大小、能帶間隙、光吸收及電子電洞再結合特性之鑑定，而探討材料特性對CuFeO¬2光觸媒活性及產氫之影響。最終將CuFeO¬2光觸媒應用於雙觸媒系統，進行光分解水反應。
研究結果發現，以0.5 g EDFS•3H2O作為前驅物，在1 L/min流通空氣下，經530 ℃之熱處理後，可成功地合成高結晶性之α-NaFeO2；放大產量後，3 g EDFS•3H2O作為前驅物，1 L/min流通70% O2下，經530 ℃之熱處理後，可獲得高純度之α-NaFeO2產物。以α-NaFeO2作為前驅物，在350 ℃之熔融CuCl中，經Na＋-Cu＋離子交換，可合成純相之CuFeO2，其燒結程度低於在500 ℃及450 ℃之熔融CuCl中合成之純相CuFeO2；在350 ℃之熔融CuCl中，以具有α-NaFeO2及β-NaFeO2的混合產物作為前驅物，經Na＋-Cu＋離子交換，可成功地合成具有最高的光觸媒活性之CuFeO2。
最後將CuFeO2作為水分解產氫光觸媒，與實驗室另一研究的Bi20TiO32作為水分解產氧光觸媒，兩者結合應用於雙光子光觸媒系統 (Z-scheme)。在本實驗室設計之雙槽光觸媒系統，以銅線做為雙槽反應間的電子傳導媒介，成功地分別於光陰極及光陽極槽產出氫氣與氧氣。

CuFeO2 photocatalyst has a band gap of 1.34 eV, where the light of the entire solar spectrum can almost be fully harvested. Thus, the material is considered as one photocatalyst of great potential to utilize and convert solar energy. In literature, the synthesis of CeFeO2 has to be conducted at high temperatures and it is greatly influenced by the calcination atmosphere. Consequently, it is rather difficult to obtain CuFeO2 in pure phase. In this study, weuse Na [EDTA-Fe]．3H2O as the precursor to obtain α-NaFeO2 by thermal decomposition. An Na+-Cu+ ion exchange reaction is successfully employed to transform the prepared α-NaFeO2 into CuFeO2 photocatalystat a relatively low temperature. Crystal structure and size of CuFeO2 synthesized at different conditions were characterized by XRD, SEM and TEM. Optical properties of CuFeO2 were determined by visible-infrared spectrum. Trends in the carrier recombination of CuFeO2 were characterized by photoluminescence spectrum as well.
The results showed thathigh crystallinity of the α-NaFeO2 with layer-structuredcan be synthesized by 0.5 g EDFS．3H2O as the precursor under 1 L/min flow of air at 530 ℃. By studying issues associated with the scale-up of the production process, 3 g EDFS．3H2Ocan be further used to the α-NaFeO2 under 1 L/min flow of 70% O2 at 530 ℃. Furthermore, CuFeO2 can be synthesized by Na+-Cu+ ion exchanging α-NaFeO2 with the molten CuCl at 350 ℃. At this temperature, the sintering effect is less dominant than results at at 500 ℃ and 450 ℃. In fact, the highest photocatalytic activity of CuFeO2 can be successfully obtained by dissolved precursor of mixed α-NaFeO2 and β-NaFeO2.
Finally, the photocatalytic CuFeO2 has been successfully demonstrated to be capable of generating hydrogen in an aqueous methanol solution. By integrating a Bi20TiO32 as oxygen production catalyst, which is a parallel work from our laboratory, a Z-scheme water splitting system is realized through a twin reactor with copper wire as the electron transfer medium between two chambers. Hydrogen and oxygen can be successfully produced at the photocathode and photoanode chambers in such a twin reactor system, respectively.

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