We demonstrate high contrast gasochromism in a thin film produced by combining chromic Prussian blue nanoparticles and catalytic platinum nanoparticles, applied by sequential wet-coating onto a substrate. The contrast ratio at 700 nm reaches 80. The cycle stability exceeds 200 cycles. H₂ with low concentration (4%-H₂) and air can drive the change of colour between blue and colourless. We also reveal via X-ray diffraction, Fourier-transform IR spectroscopy, and investigation of the redox potential of a series of metal-substituted Prussian blue analogues, that bleaching results from the reduction of Prussian blue nanoparticles by protons generated using platinum nanoparticles.

中文翻译：

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含铬和催化纳米颗粒的可湿处理薄膜的高对比度气相致变色†

我们证明了通过将铬酸普鲁士蓝纳米颗粒和催化铂纳米颗粒相结合而产生的薄膜中的高反差气相致变色，该薄膜通过顺序湿法涂覆到基材上而得到。700 nm处的对比度达到80。循环稳定性超过200个循环。低浓度的H ₂（4％-H ₂）和空气可以驱动蓝色和无色之间的颜色变化。我们还通过X射线衍射，傅立叶变换红外光谱和一系列金属取代的普鲁士蓝类似物的氧化还原电位的研究揭示了漂白是由于铂纳米颗粒产生的质子对普鲁士蓝纳米颗粒的还原作用所致。