Smart windows are a promising way to modulate solar light transmittance, which is crucial for energy saving buildings. Current challenges focus on designing hydrogel materials that have multi-functionality, low cost, a fabrication process suitable for mass production, and durability. Here in this review, we provide an overview of the recent progress in hydrogel-based smart windows in different categories (thermo-, electro- and humidity-stimuli), focusing on the functional hydrogel material selectivity, working mechanisms and device design. The challenges and opportunities of hydrogel smart windows are discussed in the perspective section.

中文翻译：

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水凝胶智能窗户

智能窗户是一种有前途的调节太阳光透射率的方法，这对于节能建筑至关重要。当前的挑战集中在设计具有多功能性，低成本，适合大规模生产的制造工艺以及耐用性的水凝胶材料上。在本文中，我们概述了基于水凝胶的智能窗在不同类别（热，电和湿度刺激）中的最新进展，重点是功能性水凝胶材料的选择性，工作机理和设备设计。透视部分讨论了水凝胶智能窗户的挑战和机遇。