Crackle‐Templating and Defect‐Healing Electrodeposition for Cu/CuS Mesh Films: Enabling Corrosion‐Resistant High‐Performance Transparent Electronics

Abstract The advancement of flexible transparent electrodes (FTEs) faces the challenge of simultaneously enhancing electrical conductivity, optical transparency, and chemical/mechanical stability. This study innovatively employs a thin‐film crackle self‐templating method combined with vacuum‐deposited Cu seed layers to fabricate large area demonstrable, high‐performance Cu transparent mesh films. Electrodeposition is utilized to precisely repair disconnected conductive networks. Concurrently, an in situ sulfidation technique is implemented, forming a dense protective layer of CuS nanosheets on the Cu mesh surface. This endows the film with exceptional chemical stability, exhibiting no performance degradation under harsh conditions, including various types of strong acids/alkalis (pH 1–13), high‐temperature humidity (85 °C/85% RH, duration > 100 h), adhesion test, ultrasonic impact, and 1000 bending cycles (bending radius = 2 mm). The resulting composite film (Cu/CuS micro‐network) achieves a breakthrough ultra‐low sheet resistance of 0.1 Ω/sq at 80%@550 nm transmittance (Figure of Merit = 16 382, haze = 5.52%@550 nm, excluding the effects of the PVA/PVP layer and PET substrate). The fabricated film demonstrates highly efficient electrothermal conversion (>100 °C within 60 s at 1 V, efficiency exceeding 60%). This work provides a large‐area demonstrable, corrosion‐resistant transparent electronic platform promising for applications in wearable electronics, automotive electronics, and smart environments.