Review on the Synthesis and Antioxidation of Cu Nanowires for Transparent Conductive Electrodes

Abstract

Transparent conducting films based on solution-synthesized copper nanowires (Cu NWs) are considered to be an attractive alternative to indium tin oxide (ITO) due to the relative abundance of Cu and the low cost of solution-phase NW coating processes. Moreover, transparent electrodes tend to be flexible. This makes Cu NWs more attractive because ITO is brittle and can not meet the requirements of flexibility. For Cu NWs, aspect ratio is an important property. Cu NWs can be directly prepared by chemical reduction with various reducing agents and suitable capping agents. In general, the selectivity of the capping agent is very important for the formation of one-dimensional nanostructures because it plays a major role in the thermodynamic regulations and growth kinetics that influence the geometry and morphology of the crystal facets. Therefore, different aspect ratios are formed. Conductivity is the most important property for transparent electrodes. Organic pickling, annealing and glare pulses have a certain improvement in conductivity. Meanwhile, it is also essential to increase the oxidation resistance of the transparent electrode. The reduction of graphene oxide (r-GO), the coating of metal and polymer improve the oxidation resistance of the transparent electrode to varying degrees. This paper reviews the effect of different capping agents on the aspect ratio of NWs, and the effects of different post-treatments on oxidation resistance and conductivity of transparent electrodes.

Toward Next‐Generation Smart Windows: An In‐depth Analysis of Dual‐Band Electrochromic Materials and Devices

“…[81,82] With the rising demand for flexible wearable electronic devices, [14,78,79] there's a shift toward alternative transparent conductive layers. These include C-based materials such as graphene [83,84] and carbon nanotubes, [85,86] metal nanowires such as Ag nanowires, [87,88] metal grids/meshes, [89,90] and conductive polymers such as PET [78,79] and PEDOT:PSS. [91,92] These developments are pivotal for the broader commercialization of electrochromic technology.…”

Highly Stable Copper Nanowire-Based Transparent Conducting Electrode Utilizing Polyimide as a Protective Layer

“…Several methods have been developed to prepare Cu NWs with a controlled morphology. , However, Cu readily oxidizes in air, causing deterioration of the performance of a device, which remains a major bottleneck for the realization of Cu-based TCEs. − Despite the advancement in mitigation methods, most of the efforts are not completely successful, and fabrication of air-stable Cu-based TCEs remains a challenge. , Specific experimental conditions need to be maintained during the fabrication, and a careful selection of surfactants is needed to passivate the surface of Cu NWs. , Therefore, the protocols that have been developed for other metal NWs, such as gold and silver NWs, are not suitable for Cu NWs. ,, Apart from the stability issues, pristine Cu NWs form an inhomogeneous dispersion that restricts their use in ink for coating on transparent substrates. For obvious reasons, additives, in the form of surface passivating or dispersion agents during TCE fabrication, play a critical role for Cu NWs. , No single additive is found to be effective for simultaneous manipulation of the shapes of Cu nanocrystals and the prevention of the surface oxidation.…”

“…28,29 Specific experimental conditions need to be maintained during the fabrication, and a careful selection of surfactants is needed to passivate the surface of Cu NWs. 30,31 Therefore, the protocols that have been developed for other metal NWs, such as gold and silver NWs, are not suitable for Cu NWs. 26,32,33 Apart from the stability issues, pristine Cu NWs form an inhomogeneous dispersion that restricts their use in ink for coating on transparent substrates.…”

Controllable fabrication and self-assembly of Cu nanostructures: the role of Cu2+ complexes

“…Copper (Cu), as one of the most important metals in modern industry, has attracted considerable attention also in nanoscale fabrication, especially by the solution phase reduction method. [11][12][13][14][15][16][17][18][19][20] In the literature, various Cu nanostructures such as nanoparticles, 11,12 nanowires, 13-15 nanoplates 16,17 and nanotrees 18,19 have been successfully fabricated or assembled by the solution phase reduction approach. Although signicant research efforts have been made, there is still a lack of a universal and effective strategy for both fabrication and selfassembly of Cu nanostructures, with precise morphological control.…”