Additive Manufacturing of Large-scale Metal Mesh with Core-shell Composite Structure for Transparent Electromagnetic Shielding/glass Heater

Transparent electromagnetic (EM) shielding glass with a metal mesh has significant potential for application in different fields of EM radiation and anti-EM interference light-transmitting observation windows. In particular, a transparent EM-shielding glass with a large-aspect-ratio metal mesh can effectively alleviate the contradictory problems of shielding effectiveness and light-transmission performance constraints. However, the fabrication of high-aspect-ratio metal meshes on glass substrates has problems such as high cost, complex processes, low efficiency, small area, and easy damage issues, which limit their application in the field of high-performance, transparent EM-shielding glass. Therefore, this paper proposes a composite additive manufacturing process based on electric-field-driven microjet 3D printing and electroplating. By fabricating metal meshes with an Ag-Cu core-shell structure on a glass substrate, EM-shielding glass with high shielding efficiency and light transmission can be manufactured without increasing the aspect ratio of the metal meshes. The prepared Ag-Cu composite metal mesh has excellent optoelectronic properties (period 250 μm, line width 10 μm, 90.1% transmission at 550 nm visible light, square resistance 0.21 Ω/sq), efficient electrothermal effect (3 V DC voltage can reach 189 °C steady-state temperature), stable EM-shielding effectiveness (average shielding effectiveness 23 dB at X-band), and acceptable mechanical and environmental stability (less than 3% change in square resistance after 150-times adhesion test and less than 6% and 0.6% change in resistance after 72 h in acid and alkali environments, respectively). This method provides a new solution for the mass production of high-performance large-area transparent electric heating/EM-shielding glass.