這是第一個成功利用水熱法合成純相鐵酸鉍材料於ITO導電基板上的研究。先使用旋轉塗佈法將鐵酸鉍晶種層長在ITO導電基板上，接著使用1克氫氧化鈉在180度持溫4.5小時水熱法合成單晶鐵酸鉍。由選區繞射圖可以看到晶種層為含有(010)及(-110)面的多晶鐵酸鉍，在晶種上層的為包含(-110)(010)及(-120)面的單晶鐵酸鉍，其中鉍和鐵的元素成分比為1:1。然而如果水熱法直接成長於沒有晶種的地方會得到奈米線形狀的Fe2O3。
非對稱的電流密度-電壓曲線顯示其獨有的壓電子效應，當施加的壓力變大電流密度在負偏壓下往負的方向增加，這是因為蕭特基位障從32mV (2.12 GPa)降低至22mV (1.25 GPa)導致。壓電光催化效應是指在施加固定壓力及超聲波震動於鐵酸鉍團聚物上可以加強其降解MB的效率，因為減少了載子的抵消及再結合，其速率常數k值(0.003min-1)為沒施壓力的3倍高。

The pure BiFeO3 was successfully fabricated on the ITO/glass substrate for the first time using spin coating for grow a seed layer first and subsequently employing hydrothermal method using the condition of 1 g NaOH at 180 C for 4.5 hrs.
The SAED shows polycrystalline-like patterns of seed layers, in which the (010), and (-110) planes of BFO were observed. The film formed on the polycrystalline BFO seed layer is the single crystalline BFO. The corresponding SAED pattern shows the (-110), (010), and (-120) planes of BFO. The EDS analysis indicated approximately Bi:Fe = 1:1. However, if the film grew directly on the ITO/glass substrate without seed layers, polycrystalline nanowire-like Fe2O3 impurity was formed.
The asymmetrical current density-voltage curve showed piezotronic properties of BFO agglomerates. JD under negative bias was negatively enhanced when the applied stress was increased. This enhancement was attributed to the lowering of the Schottky barrier height, which was lowered from approximately 32 mV (at 2.12 GPa) to approximately 22 mV (at 1.25 GPa). The variation as a function of applied pressure was found to follow an approximate first-order relationship.
The piezophotocatalysis indicated that introducing fixed pressure using a transparent glass and ultrasonic vibration on the BFO agglomerates in a 2-ppm MB solution resulted in substantially enhanced photocatalysis, compared with that of the BFO sample only without any other external stresses. This was attributed to alternating vibration which reduced the charge screening and dissipation, thus improving BFO agglomerates active sites and enhancing MB mass transfer. The photodegradation kinetic behavior showed the first-order linear relationship for each sample. The BFO sample under pressure from ultrasonic vibration and a piece of glass exhibited a k value of approximately 0.003 min-1, which is approximately 3 times higher than that of BFO without any stress.

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