Study of seamless Au mesh flexible transparent heaters: Influence of mesh coverage

Here, we report on the experimental and theoretical understanding of seamless junction Au mesh network flexible transparent heaters. Three Au mesh transparent conductors (TCs) are fabricated using the photolithography-etching process to compare the influence of metal surface coverage on their electrical and thermal performance. The fabricated mesh networks are quite transparent (T ~ 80%) in the 400-900 nm spectral region and exhibit small variation in sheet resistance (ΔRmax ~ 0.12, 0.05, and 0.22 −1) under different bending radii (minimum radii of ~7.5 mm). The Au mesh with large surface coverage (i.e. ~4.8%) exhibited the highest figure of merit (1035), and the Au mesh with small surface coverage (i.e. ~2.5%), which eventually tested as a heater, exhibited the highest thermal efficiency (i.e. 249 °C/(W/cm2)) and temperature of 150 °C at the lowest input power (0.5 W cm−2). A 1D analytical heat transfer model is developed for quick estimation of temperature of heater samples. The thermal simulation of heaters is carried out using an ANSYS tool. The experimental, simulation and 1D analytical results are compared and validated, revealing that the simulation results are more aligned with experimental results. The flexible TCs with short response time and high thermal resistance are very useful in various flexible heating applications.