Intelligent optimization algorithms-assisted design of quad-mode smart window based on GST and VO₂ for all-season...

Energy consumption in the construction sector is escalating rapidly, making smart windows with efficient multi-spectral thermal regulation critical for energy conservation and occupant comfort. However, existing smart windows are predominantly limited to 2-3 sequential or non-independent switching modes, failing to adapt to dynamic all-season and day-and-night compatible conditions. Herein, we report a quad-mode smart window structure designed via intelligent optimization algorithms (IOA) assistance, far outperforming traditional brute-force approaches, integrating two phase-change materials (PCMs: GST and VO₂) for independent and synergistic spectral regulation. The structure comprises a functional layer composed of a stack of multiple materials and a stable Ag and SiO₂ substrate, enabling four independently switchable modes. GST independently modulates visible transmittance, while VO₂ controls infrared emissivity in the 8-13 µm atmospheric window. Theoretical characterizations demonstrate a solar modulation efficiency of 29.3%, a maximum cooling effect of 3.2°C, and a heating enhancement of 1.5°C compared to normal glass. Additionally, the structure maintains robust spectral stability under 15% fabrication tolerance perturbations. This IOA-designed, PCM-integrated quad-mode smart window achieves unprecedented adaptability to complex environments, offering significant potential for high-efficiency building energy savings and multi-functional optical device applications.