A facial method is demonstrated here for the controllable fabrication of nano-NbN with three-dimensional cotton like structure. It is composed of two-step synthesis strategy and uses ammonia as nitrogen source. The prepared NbN has three-dimensional cotton like structure formed by nanoparticles with a size of around 20[Formula: see text]nm. It is found that the temperature of nitriding has a great influence on the size of crystal grain. 800∘C is the most appropriate temperature to form this special structure of nano-NbN. As a catalyst for oxygen reduction reaction, nano-NbN is discovered to have a significant property, which is much better than that of niobium nitride prepared from oxide precursor without any treatment. Inspired by this strategy, the electrocatalytic performance of transition metal nitrides in nanoscale can be better studied.

中文翻译：

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用于氧还原反应的三维棉状结构纳米NbN的可控制备

这里展示了一种面部方法，用于可控制造具有三维棉状结构的纳米 NbN。它由两步合成策略组成，以氨为氮源。制备的NbN具有由纳米颗粒形成的三维棉状结构，尺寸约为20[公式：见正文]nm。发现氮化温度对晶粒尺寸有很大影响。800∘C是形成纳米NbN这种特殊结构的最合适温度。作为氧还原反应的催化剂，发现纳米NbN具有显着的性能，远优于未经任何处理的氧化物前驱体制备的氮化铌。受该策略的启发，可以更好地研究过渡金属氮化物在纳米尺度上的电催化性能。