To achieve simultaneously higher transparency and heat-shielding performance of Cs_xWO₃ for energy-saving glass applications, we developed small size Cs_xWO₃ nanorods with lengths of 10–60 nm by controllable solvothermal reaction and a subsequent heat-treatment with citric acid thermolysis under a N₂ atmosphere. It has been proved that crystal growth could be controlled by using solid state gel-like tungstic acid as the W source and controlling the water content in the precursor solution. In the meantime, the deposited carbon film on the particle surface due to thermolysis of citric acid during N₂ heat-treatment could also inhibit the crystal growth. It has been confirmed that the as-prepared Cs_xWO₃ films on a glass substrate from dispersion of Cs_xWO₃ particles after N₂ heat-treatment with citric acid thermolysis exhibited improved transparency and near-infrared (NIR) shielding ability. Particularly, the Cs_xWO₃ particles synthesized using pure ethanol as the solvent exhibited the best visible light transparency and NIR shielding performance. The mechanism of controlling the small size and improving the visible light transparency and NIR shielding ability of Cs_xWO₃ particles was discussed, which is of significance for realizing broad applications in the field of energy-saving glasses, and the synthetic strategy is also suitable for synthesizing other small size functional nanoparticles.

中文翻译：

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可控合成的小尺寸Cs _x WO ₃纳米棒作为透明隔热膜添加剂

为了在节能玻璃应用中同时实现更高的Cs _x WO ₃透明性和隔热性能，我们通过可控的溶剂热反应以及随后的柠檬酸热处理开发了尺寸为10–60 nm的小尺寸Cs _x WO ₃纳米棒。 N ₂气氛下进行酸热解。已经证明可以通过使用固态凝胶状钨酸作为W源并控制前体溶液中的水含量来控制晶体生长。同时，由于N ₂期间柠檬酸的热分解，在颗粒表面上沉积的碳膜热处理也会抑制晶体的生长。已经证实，由柠檬酸热解的N ₂热处理后的Cs _x WO ₃颗粒的分散体在玻璃基板上制备的Cs _x WO ₃膜表现出改善的透明性和近红外（NIR）屏蔽能力。特别地，使用纯乙醇作为溶剂合成的Cs _x WO ₃颗粒表现出最佳的可见光透明性和NIR屏蔽性能。控制Cs _x WO ₃的小尺寸并提高可见光透明度和NIR屏蔽能力的机制 讨论了纳米粒子，这对于实现在节能玻璃领域的广泛应用具有重要意义，并且该合成策略也适用于合成其他小尺寸的功能纳米粒子。