Department of Science and Technology (ITN), Campus Norrköping, Linköping University, SE-60174 Norrköping, Sweden; E-Mails:
Sensors (Basel). 2009;9(11):8911-23. doi: 10.3390/s91108911. Epub 2009 Nov 9.
ZnO nanotubes and nanorods grown on gold thin film were used to create pH sensor devices. The developed ZnO nanotube and nanorod pH sensors display good reproducibility, repeatability and long-term stability and exhibit a pH-dependent electrochemical potential difference versus an Ag/AgCl reference electrode over a large dynamic pH range. We found the ZnO nanotubes provide sensitivity as high as twice that of the ZnO nanorods, which can be ascribed to the fact that small dimensional ZnO nanotubes have a higher level of surface and subsurface oxygen vacancies and provide a larger effective surface area with higher surface-to-volume ratio as compared to ZnO nanorods, thus affording the ZnO nanotube pH sensor a higher sensitivity. Experimental results indicate ZnO nanotubes can be used in pH sensor applications with improved performance. Moreover, the ZnO nanotube arrays may find potential application as a novel material for measurements of intracellular biochemical species within single living cells.
在金薄膜上生长的氧化锌纳米管和纳米棒被用于制造 pH 传感器器件。所开发的氧化锌纳米管和纳米棒 pH 传感器具有良好的重现性、可重复性和长期稳定性，并在大的动态 pH 范围内显示出与 Ag/AgCl 参比电极的 pH 依赖性电化学电位差。我们发现，与氧化锌纳米棒相比，氧化锌纳米管的灵敏度高达两倍，这可以归因于小尺寸氧化锌纳米管具有更高水平的表面和次表面氧空位，并提供更大的有效表面积，具有更高的表面积与体积比，从而使氧化锌纳米管 pH 传感器具有更高的灵敏度。实验结果表明，氧化锌纳米管可以用于 pH 传感器应用，以提高性能。此外，氧化锌纳米管阵列可能作为一种新型材料，用于测量单个活细胞内的细胞内生化物质。
