• A Janus smart window integrating polymer-stabilized liquid crystal and thermochromic materials achieves dual electro-thermal control, enabling dynamic adjustment of solar transmittance and infrared emissivity.
• Outdoor tests demonstrate significant temperature regulation: indoor temperature drops by 8 °C during daytime and 5 °C at night, with simulated cooling powers of 93 W m−2 (day) and 142 W m−2 (night).
• The window also provides electromagnetic interference shielding in the X-band (8.2–12.4 GHz), adding multifunctionality for smart building applications.
• Energy simulations show superior energy savings across various climate zones compared to conventional smart windows and standard glass, highlighting its potential for green buildings.