Jiang Mingrui, Chen Fangming, Meng Yao, Yang Qiaoyu, Wang Jian, Zhang De-Wen, Wang Yaqiong
Institute of Medical Engineering, Department of Biophysics, School of Basic Medical Sciences, Health Science Center, Xi'an Jiaotong University, Xi'an, 710061, China.
Institute of Medical Engineering, Department of Biophysics, School of Basic Medical Sciences, Health Science Center, Xi'an Jiaotong University, Xi'an, 710061, China; Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China, Xi'an, 710061, China.
Talanta. 2023 Mar 1;254:124124. doi: 10.1016/j.talanta.2022.124124. Epub 2022 Nov 24.
The application of silicon (Si) substrate as photoelectrode in light-addressable electrochemistry (LAE) is severely limited due to its ease of surface oxidation. The resulted silicon oxide (SiO) layer is electronically insulating and blocks charge transfer between the electrode and electrolyte. Keeping the Si from being oxidized is a key challenge for its practical use as a semiconductor electrode. In this work, we find that by developing a thin layer of polydopamine film on the surface of Si substrate, followed by carbonization at 550 °C, the natural oxidation of Si substrate can be successfully forestalled. When applied as an electrode, it is further found that the carbonized polydopamine (cPDA) layer can also prevent anodic oxidation of Si. The cPDA layer-modified Si substrate exhibits good photoelectrochemical performance and great stability, with no obvious signal decrease under ambient environment over 32 h. Our work here provides a new modification strategy for anti-oxidation of Si substrate and it is promising in the application of light-addressable electrochemical sensing and imaging.
由于硅（Si）衬底易于表面氧化，其在光寻址电化学（LAE）中作为光电极的应用受到严重限制。生成的氧化硅（SiO）层具有电子绝缘性，会阻碍电极与电解质之间的电荷转移。防止硅被氧化是其作为半导体电极实际应用的关键挑战。在这项工作中，我们发现通过在硅衬底表面制备一层聚多巴胺薄膜，然后在550℃碳化，可以成功阻止硅衬底的自然氧化。当用作电极时，还发现碳化聚多巴胺（cPDA）层可以防止硅的阳极氧化。cPDA层修饰的硅衬底表现出良好的光电化学性能和稳定性，在环境条件下32小时内信号无明显下降。我们的工作为硅衬底的抗氧化提供了一种新的修饰策略，在光寻址电化学传感和成像应用中具有广阔前景。
