Nanowires refer to linear nanomaterials with a diameter of 10-100nm on the nanometer scale and a length of up to the order of micrometers. Nanowires are one-dimensional nanomaterials. In electronics, optoelectronics, and nanoelectromechanical devices, nanowires may play an important role. It can also be used as additives in composites, wiring in quantum devices, field emitters and biomolecular nanosensors.

Figure 1. Application of transparent conductive film of nanometer silver wire.

Applications:

• Solar energy conversion: Nanowires can naturally gather sunlight into a very small area in the crystal, and the light-gathering capacity is 15 times that of the intensity of ordinary light. Since the diameter of the nanowire crystal is smaller than the wavelength of the incident sunlight, it can cause the resonance of the light intensity inside and around the nanowire crystal. The typical solar energy conversion efficiency limit has always been the bottleneck of solar cell efficiency. Nanowires may increase this conversion efficiency limit by several percentage points, which will have a significant impact on the development of solar cells, the utilization of nanowires based solar energy and global energy development.
• Catalyst: Nanowires have uniform size, high aspect ratio, and high catalytic properties. Nanowires can catalyze redox reactions, and the reaction is controlled by the diffusion and transfer of oxygen on the electrode surface.
• Conductive material: Transparent conductive film is a kind of film that can conduct electricity and has high transparency in the visible light range. Therefore, it is necessary to take both into account for the conductive film. However, the conductivity of the conductive film is negatively related to the transparency, that is, the larger the film thickness value, the better the corresponding conductivity, but the poorer the light transmittance. Therefore, materials with excellent conductivity and light transmittance are the key to preparing conductive films. The special structure of the size-to-diameter ratio effect of nanowires makes it have high transparency, low haze, high conductivity, and excellent toughness, which makes it occupy an important position in the field of transparent conductive film materials. The nanowires are coated on the substrate by different film forming methods to make a transparent conductive film that can be used to prepare flexible devices.
• Optical devices: Nanowires not only have good electrical and thermal conductivity, but also have their own unique high transparency and are also widely used in optical devices and other fields. In addition, nanowires can also be used as a carrier for surface-enhanced plasma and are widely used in surface-enhanced Raman spectroscopy (SERS) testing to achieve highly sensitive and non-destructive testing.
• Sensors: Nanowires are widely used in the sensor field due to their good heat transfer, conductivity, biocompatibility and antibacterial properties.

References:

1. Chuang Zhang, Yongli Yan, Yong Sheng Zhao and Jiannian Yao. Synthesis and applications of organic nanorods, nanowires and nanotubes [J]. Annu. Rep. Prog. Chem., Sect. C: Phys. Chem., 2013, 109, 211- 239.
2. Hui Xia, Caiyun Hong, Xiaoqin Shi, Bo Li, Guoliang Yuan, Qiaofeng Yao and Jianping Xie. Hierarchical heterostructures of Ag nanoparticles decorated MnO₂ nanowires as promising electrodes for supercapacitors [J]. J. Mater. Chem. A, 2015, 3, 1216-1221.
3. Jianfeng Zhou, Cecilia Yu, Ting Wang and Xing Xie. Development of nanowire-modified electrodes applied in the locally enhanced electric field treatment (LEEFT) for water disinfection [J]. J. Mater. Chem. A, 2020, 8, 12262-12277.