The polar and piezoelectric nature of the wurtzite structure of ZnO nanowires with a high aspect ratio at nanoscale dimensions is of high interest for piezotronic and piezoelectric devices, but a number of issues related to polarity are still open and deserve a particular attention. In this context, chemical bath deposition offers a unique opportunity to select the O- or Zn-polarity of the resultant nanowires and is further compatible with the fabrication processes of flexible devices. The control and use of the polarity in ZnO nanowires grown by chemical bath deposition open a new way to greatly enhance the performance of the related piezotronic and piezoelectric devices. However, polarity as an additional tunable parameter should be considered with care because it has a strong influence on many processes and properties. The present review is intended to report the most important consequences related to the polarity in ZnO nanowires for piezotronic and piezoelectric devices. After introducing the basic principles involving crystal polarity in ZnO, a special emphasis is placed on the effects of polarity on the nucleation and growth mechanisms of ZnO nanowires using chemical bath deposition, defect incorporation and doping, electrical contacts and device properties.

具有高纵横比的纳米尺寸的ZnO纳米线的纤锌矿结构的极性和压电性质在压电和压电器件中引起了人们的极大兴趣，但是与极性有关的许多问题仍然悬而未决，值得特别注意。在这种情况下，化学浴沉积为选择所得纳米线的O或Zn极性提供了独特的机会，并且进一步与柔性器件的制造工艺兼容。通过化学浴沉积法生长的ZnO纳米线中极性的控制和使用开辟了一条新途径，可以大大提高相关压电和压电器件的性能。但是，应谨慎考虑将极性作为附加的可调参数，因为极性会对许多过程和特性产生重大影响。本综述旨在报告与压电和压电器件用ZnO纳米线中的极性有关的最重要结果。在介绍了涉及ZnO中晶体极性的基本原理之后，我们特别强调了极性对使用化学浴沉积，缺陷掺入和掺杂，电接触和器件性能的ZnO纳米线的成核和生长机理的影响。