Sodium alginate grafted phase-changing electrolyte for energy-efficient thermochromic and electrochromic synergy with uniquely tunable optical states and simultaneous Vis-NIR modulation

Abstract

Conventional smart windows, limited by their single-stimulus response, often fail to meet diverse practical needs, and cannot achieve zero transmission across the Visible-NIR spectrum. Integrating thermochromic, electrochromic, and synergetic-responsiveness into a single device is both challenging and essential for effective light modulation and energy efficiency. Herein, we present a novel green phase-changing electrolyte integrated with a versatile chromogen, to create an “all-in-one” smart window. This device autonomously switches functions and can also simultaneously respond to dual-stimuli, achieving an absolute private state. The device’s tunable performance in optical contrast, switching kinetics, coloration efficiency, and cyclic stability, influenced by lattice water concentration is also meticulously assessed. Our comprehensive study highlights the device’s robust multifunctional properties, including thermal insulation, lifestyle interventions, and environmental remediation. These features make the smart window a highly energy-efficient solution with exceptional climate adaptability, such as shutting down light transmission with environmentally-benign operations and on-demand color changes. This innovative approach transforms smart windows from mere energy savers to versatile, energy-efficient systems for modern buildings. By bridging the gap between advanced materials and practical applications, our “all-in-one” smart window represents a significant advancement, paving the way for broader adoption in various environmental and energy-saving contexts.