N-TiO_2-x nanocatalysts are developed by the pulsed laser ablation in liquid (PLAL) technique, a simple and surfactant-free preparation method. The PLAL approach allows synthesizing chemical-morphological fine-tuning water TiO₂-based nanomaterials, starting from targets of different nature (powders and commercial high purity targets). The catalytic activity was investigated using methylene blue (cationic dye) and methyl orange (azo dye). A different photocatalytic response was found for the various kinds of N-TiO_2-x. In the first 20 min, under UV and visible light, about 50% and 10% of the methyl orange were removed using the N-TiO_2-x and TiO₂ colloids, respectively. In addition, we observe that the response towards the methylene blue is comparable in all the synthesized samples under UV irradiation while differing by about 30% under a visible lamp. The enhanced photocatalytic response of the N-TiO_2-x nanocatalysts with respect to the TiO₂ one is dependent on the content of the nitrogen dopant, surface area, and nitrogen-oxygen bonding configurations.

中文翻译：

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N-TiO2-x纳米催化剂：PLAL的合成和光催化活性

N-TiO _{2- x}纳米催化剂是通过脉冲激光烧蚀液体（PLAL）技术开发的，这是一种简单且无表面活性剂的制备方法。PLAL方法允许从不同性质的目标（粉末和商业高纯度目标）开始合成化学形态微调的水TiO ₂基纳米材料。使用亚甲基蓝（阳离子染料）和甲基橙（偶氮染料）研究了催化活性。对于各种N-TiO ₂ - _x，发现了不同的光催化响应。在最初的20分钟内，使用N-TiO ₂ - _x和TiO ₂在紫外线和可见光下去除了约50％和10％的甲基橙胶体。此外，我们观察到所有合成样品在紫外线照射下对亚甲蓝的响应是可比的，而在可见灯下相差约30％。N-TiO ₂ - _x纳米催化剂相对于TiO ₂的增强的光催化响应取决于氮掺杂剂的含量，表面积和氮-氧键构型。