Recrystallized ice-templated electroless plating for fabricating flexible transparent copper meshes

Abstract

Flexible transparent conductors as a replacement for indium tin oxide (ITO) have been urgently pursued due to the inherent drawbacks of ITO films. Here, we report the fabrication of flexible transparent copper meshes with recrystallized ice-crystal templates. Completely different to conventional approaches, this novel method needs neither the fabrication of mesh patterns via micro/nanofabrication technologies nor the deposition of copper through evaporation or sputtering. The linewidth and mesh size of the prepared copper meshes can be regulated, as the ice recrystallization process is controllable. Therefore, the formed copper meshes have tailorable conductivity and transparency, which are critical for optoelectronic devices. Remarkably, the electrical performance of the copper meshes is maintained even after storing for 60 days in ambient conditions or bending for 1000 cycles. This strategy is modular and can also be employed to prepare other metal meshes, such as silver meshes, offering versatile substitutes for ITO in electronic devices.rsc.li/rsc-advances 9894 | RSC Adv., 2020, 10, 9894-9901This journal is Fig. 2 The evolution of the thickness of the copper meshes with reaction time and reaction temperature. The concentration of the plating bath is 2.8 g L À1 . (a-c) The copper meshes obtained from the electroless copper plating at À3 C for (a) 25 min, (b) 120 min, and (c) 240 min. (d) X-ray diffraction spectra of PET films with and without copper meshes (the inset shows the SEM image of copper nanoparticles). (e) The change in height of the copper meshes with reaction time at different reaction temperatures. 9896 | RSC Adv., 2020, 10, 9894-9901 This journal is

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