The conventional preparation of SnNb2O6 invariably involves complex and laborious steps, which unavoidably introduces defect into the host lattice and also increases the reaction period and costs, resulting in undesired recombination of photo-generated electron-hole pairs. For the first time in this work, we manage to synthesize single-crystalline two-dimensional (2D) SnNb2O6 nanosheets with ultrathin structure through a facile one-step hydrothermal method. Comparative studies were explored to analyze the structure and phase evolution during the preparation course. The synthesized 2D structure demonstrated a narrower band gap of 2.09 eV and specific surface area of 76.1 m2 g-1, which exhibited significantly extended visible-light-responsive range and larger surface area by contrast with the state-of-the-art reports, resulting in excellent visible-light-driven photoactivity towards H2 production and water purification as well. Additionally, further enhanced photocatalytic performance was achieved by the incorporation of Pt as co-catalyst to indirectly indicate the advantage of the SnNb2O6 nanosheets in this method over other reported counterparts. It was found that, a very small amount of Pt loaded on the surface of SnNb2O6 nanosheets would contribute to remarkably higher activity than pure SnNb2O6 nanosheets and exhibit superior stability as well. Moreover, a deep insight into the underlying photocatalytic mechanism was proposed. This work sheds light on a new facile way to fabricate high-performance photocatalytic materials and provided new opportunities for solar-energy conversion.

中文翻译：

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单晶 SnNb2O6 纳米片的简便一步水热合成具有极大扩展的可见光响应，以增强光催化性能和机理洞察力

SnNb2O6 的常规制备总是涉及复杂和费力的步骤，这不可避免地会将缺陷引入主体晶格中，并且还会增加反应周期和成本，导致光生电子-空穴对的不希望的复合。在这项工作中，我们首次通过简便的一步水热法合成了具有超薄结构的单晶二维 (2D) SnNb2O6 纳米片。在准备过程中进行了比较研究，以分析结构和相演变。合成的二维结构显示出更窄的 2.09 eV 带隙和 76.1 m2 g-1 的比表面积，与最先进的报告相比，它表现出显着扩展的可见光响应范围和更大的表面积，导致对H2产生和水净化的优异可见光驱动的光活性。此外，通过掺入 Pt 作为助催化剂，进一步提高了光催化性能，从而间接表明 SnNb2O6 纳米片在该方法中优于其他报道的对应物。研究发现，负载在 SnNb2O6 纳米片表面上的极少量 Pt 将有助于比纯 SnNb2O6 纳米片具有显着更高的活性，并且还表现出优异的稳定性。此外，还提出了对潜在光催化机制的深入了解。这项工作为制造高性能光催化材料提供了一种新的简便方法，并为太阳能转换提供了新的机会。