Smart windows have been paid much attention in recent years since they can save more energy in comparison with ordinary counterparts. However, exterior heating or electric system is still required to stimulate the color/transparency responses for current smart windows, which increases the complexity of device's structure and still consumes energy. Thus, sunlight‐responsive smart windows in building are particularly appealing for saving energy but seldom reported. Herein, we propose a facile and low‐cost method to construct reversible color/transparency switching materials by integrating the unique photothermal conversion feature of noble metal nanoparticles with thermochromic compounds. The switching behavior of thermochromic materials is not triggered by traditional exterior heating but laser/sunlight irradiation. In particular, we achieve ambient sunlight‐driven photo‐thermochromic smart windows (PTCSWs) prototype which can automatically become opaque to block sunlight on scorching days and return to a transparent state under low lighting condition. We believe that this work will pave a way for a novel class of smart windows which is highly expected to be integrated into building components to tailor specific camouflage coating and substantially save energy.

The first example of amorphous CoFe hydroxide based on the electrospinning process was developed, which was used as an efficient OER catalyst.

Highly sensitive stimuli-responsive fluorescent films play an important role in smart sensors and readable optical devices. However, systems involving light-driven fluorescence changes are still limited compared with photochromic materials that simply change color upon photostimulation. Herein, by incorporation of stilbene-based molecules into a poly(vinyl alcohol) host, we have developed new flexible self-supporting nanofiber films that exhibited fast and obvious photochromic fluorescence (PCF). The reversible transfer between two fluorescent states can be easily recycled. Fluorescence microscopy and atomic force microscopy images supplied in situ evidence of changes in fluorescence and surface morphology, respectively. Density functional theoretical calculations showed that the PCF can be attributed to photoisomerization of the stilbene-based molecules. Therefore, based on the combination of experimental and theoretical studies, this work not only supplies new stilbene-based systems with light-induced fluorescence change, but also gives detailed understanding on the photoisomerization and PCF processes of the nanofibers systems. We anticipate that these PCF films can be applied in erasable memory devices and antiforgery materials, and that our strategy may be extended to other systems to fabricate multistimuli-responsive fluorescent materials.

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