Acceleration of wettability switching on TiO2 thin films under ultraviolet irradiation and direct current bias voltage
Acceleration of wettability switching on TiO2 thin films under ultraviolet irradiation and direct current bias voltage
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DOI：
10.1016/j.surfcoat.2019.02.043
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发表时间：
2019-04
影响因子：
5.4
通讯作者：
Taizou Kobayashi;S. Konishi
中科院分区：
文献类型：
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作者：
Taizou Kobayashi;S. Konishi
研究了紫外光照射和直流偏压对TiO 2薄膜光响应润湿性的影响。根据先前报道的润湿性转换机制，亲水性表面终止是由光生空穴与TiO 2表面上的桥接氧位点之间的反应引起的。在这项研究中，我们调查的效果，施加直流偏置电压的TiO 2薄膜故意向TiO 2表面的空穴，增加和加速产生的吸收网站。的润湿性切换宽度的接触角从疏水状态到亲水状态几乎翻了一番，接触角的切换时间被减少到约1/10的直流偏置电压为0.9 V和紫外线照射相结合，相比，TiO 2薄膜处理只有紫外线照射。这种基于TiO 2光催化剂的光响应润湿性开关是一种很有前途的无线液体操纵技术，因为开关宽度的放大和表面开关响应的加速对于实际应用是重要的。
This study reports the results of combining ultraviolet (UV) light irradiation and direct current (DC) bias voltage on the acceleration of the photoresponsive wettability switching of TiO2thin films. According to the mechanism of wettability switching reported previously, hydrophilic surface termination is caused by the reaction between the photogenerated holes and bridging oxygen sites on the TiO2surface. In this study, we investigate the effect of applying DC bias voltage to TiO2thin films to intentionally polarize holes toward the TiO2surface for increasing and accelerating the generation of absorption sites. The wettability switching width of the contact angles from the hydrophobic state to hydrophilic state was virtually doubled and the switching time of the contact angles was reduced to approximately 1/10th by combining a DC bias voltage of 0.9 V and UV irradiation, compared to TiO2thin films processed only with UV irradiation. This photoresponsive wettability switching based on TiO2photocatalysts is a promising technology for wireless liquid manipulation as amplification of the switching width and acceleration of the switching response of the surfaces are important for practical applications.