SnO₂-Coated Silver Nanowire Networks as a Physical Model Describing Their Reversible Domain under Electrical Stress for Stable Transparent Electrode Applications

Abstract

Thermal, electrical, and chemical instabilities affect the efficient integration of silver nanowire (AgNW) networks as transparent electrodes for energy and wearable electronics. By coupling experimental data and a simple physical model, we deduce the electrical areal power density ranges that AgNW networks can withstand, to observe either reversible modifications (i.e., electron− phonon interaction) or irreversible modifications (i.e., electrical sintering or degradation). This approach also allows us to predict the associated Joule heating temperature in the reversible domain for any applied voltage and initial resistance. It constitutes an efficient guide to design any device incorporating AgNW networks in which electrical current is applied. To improve AgNW stability, tin oxide (SnO 2 ) coating has been deposited by atmospheric-pressure spatial atomic layer deposition at 200 °C. For a similar initial resistance, the observed maximum areal power density increases from 1.6 to 3.3 W cm −2 for bare AgNWs and 40 nm-SnO 2 /AgNW networks, respectively, and their associated Joule heating temperatures are 220 and 410 °C, respectively. In addition to the high electrical stability of SnO 2 /AgNW nanocomposites, we demonstrate their enhanced stability when exposed to either thermal stress up to 400 °C, or environmental stress with 80% of relative humidity at 70 °C for 2 weeks.

Exploring the degradation of silver nanowire networks under thermal stress by coupling in situ X-ray diffraction and electrical resistance measurements

“…To address this issue, significant attention has been devoted to the effects of coatings, aimed at enhancing the AgNW stability under thermal stress. 12 For instance, we have previously demonstrated that even thin SnO 2 coatings 15,17 deposited by Atmospheric Pressure Spatial Atomic Layer Deposition (AP-SALD) can significantly enhance the thermal stability of AgNW networks.…”

“…42 The AP-SALD growth of SnO 2 thin films was carried out using tin( ii ) acetylacetonate (Sn(acac) 2 ) and water as precursors. 17,43 The samples were positioned 150 μm away from the injection head. During the deposition process, the growth rate of SnO 2 deposition performed at 200 °C was approximately 1.2 nm min −1 .…”

“…9 However, SnO 2 /AgNW nanocomposites have only been investigated in a few recent articles. 15,17–21…”

Silver Nanowire-Based Transparent Electrodes for V2O5 Thin Films with Electrochromic Properties

“…The utilized AP-SALD employed a proximity method relying on a gas manifold. A detailed explanation of the experimental procedure and deposition parameters used can be found in refs ,, . The distance between the substrate and the AP-SALD head was set to 150 μm.…”

“…An alternative low-cost and fast coating method is atmospheric-pressure spatial atomic layer deposition (AP-SALD). Several reports have shown that this technique is capable of producing high-quality conformal films on the AgNWs, such as ZnO, , Al:ZnO, and SnO 2 . , The coatings improved the stability of AgNWs, since the metal oxide layer hinders the surface diffusion of the Ag atoms from nanowires, thus maintaining the integrity and stability of the nanowire morphology. For most oxides, the stability of AgNWs improves as the coating thickness increases.…”