作為一個新穎的材料，ZnSnO3已被證明在許多方面具備優秀的性質，一般來說，ZnSnO3被應用於氣體偵測或是光觸媒，但其壓電性質也同樣優異。此外，其半導體特性也使得ZnSnO3擁有壓電子效應，這表示我們得以利用壓力來改變壓電所產生的壓電位，進而使得蕭基能障和電子傳輸行為改變，對於不同的電子元件來說，我們能夠藉此來調整能帶結構，並增幅其原本的效能。若材料本身具備光激發的特性，則更可藉由壓電光電子效應來將三種效應耦合，來達到強化光電元件的效果。
目前來說，尚未有任何文獻紀載將光催化反應以及壓電光電子效應結合並將其應用的研究文章，亦尚無有研究團隊成功製備出一維奈米結構之ZnSnO3，在本篇研究中，我們以兩步驟水熱法成功地在FTO導電玻璃上合成出一維奈米結構的ZnSnO3，並將其用來研究關於壓電光電子效應和光催化反應的結合，亦即壓電光觸媒轉化有機物的效率。

Studies have reported various excellent properties of the novel lead-free ZnSnO3 material applied to gas sensors and photocatalyst. However, the piezoelectric performance of ZnSnO3 did not obtain an equivalent attention. In addition, its semiconductor characteristics allow to exhibit the piezotronic effect, which means stress modulation of piezo-potentials built in the Schottky contact to enable different electrical performances of a device. If the system also exhibits the photonic features under light irradiation, the piezo-phototronic effect is developed. These characteristics were not observed in most of materials.

No studies reported the piezo-photocatalytic effect, which is a coupling between the piezophototronic and photocatalytic effects. In this work, 1D nanostructured ZnSnO3 nanowires were fabricated using a two-step hydrothermal reaction to explore the novel piezo-related properties for the first time.

The X-ray diffraction pattern and TEM analyses showed that the ZnSnO3 phase of single crystalline nanowires. The piezotronic and piezophototronic effects were demonstrated using a probe station, which enabled to quantitatively apply stresses during the I-V measurement. We found the Schottky barriers were modulated as a function of applied stresses at the local contacts between the probe and the sample. These features implied the novel application to piezo-photocatalysis.

In the piezo-photocatalytic experiment, we found the piezo-phototronic effect did significantly enhance the photocatalytic efficiency of ZnSnO3 nanowires without any other external bias. An energy band diagram was simply used to explain the increased efficiency, which was attributed to the improved mobility of photogenerated carriers, resulting from the enhanced piezo-potentials under stresses.

There still exists numerous challenges for this project to further enhance the piezo-related properties of ZnSnO3, including 1) fabrication of much well-aligned ZnSnO3 nanowires, 2) fabrication of different aspect ratios (morphology) of ZnSnO3, 3) seeking less basic conditions (pH < 12.5) for growing ZnSnO3 nanowires, 4) growing ZnSnO3 on a flexible substrate. Various promising applications, such as sensors and photoelectrochemical cells, can then be expected.

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