Materials Science Centre, Indian Institute of Technology , Kharagpur, W.B. 721 302, India.
ACS Appl Mater Interfaces. 2017 Mar 22;9(11):9669-9680. doi: 10.1021/acsami.6b16456. Epub 2017 Mar 13.
The effective surface area of the nanostructured materials is known to play a prime role in catalysis. Here we demonstrate that the shape of the nanostructured materials plays an equally important role in their catalytic activity. Hierarchical CdS microstructures with different morphologies such as microspheres assembled of nanoplates, nanorods, nanoparticles, and nanobelts are synthesized using a simple hydrothermal method by tuning the volume ratio of solvents, i.e., water or ethylenediamine (en). With an optimum solvent ratio of 3:1 water:en, the roles of other synthesis parameters such as precursor's ratio, temperature, and precursor combinations are also explored and reported here. Four selected CdS microstructures are used as photocatalysts for the degradation of methylene blue and photoelectrochemical water splitting for hydrogen generation. In spite of smaller effective surface area of CdS nanoneedles/nanorods than that of CdS nanowires network, the former exhibits higher catalytic activity under visible light irradiation which is ascribed to the reduced charge recombination as confirmed from the photoluminescence study.
众所周知，纳米结构材料的有效表面积在催化中起着主要作用。在这里，我们证明纳米结构材料的形状在其催化活性中同样起着重要作用。通过调节溶剂（即水或乙二胺（en））的体积比，使用简单的水热法合成了具有不同形态的分级 CdS 微结构，例如纳米板、纳米棒、纳米颗粒和纳米带组装的微球。在最佳溶剂比为 3:1 的水：en 时，还探索并报道了其他合成参数（例如前体比、温度和前体组合）的作用。将四种选定的 CdS 微结构用作光催化剂，用于亚甲基蓝的降解和光电化学水分解以产生氢气。尽管 CdS 纳米针/纳米棒的有效表面积比 CdS 纳米线网络小，但前者在可见光照射下表现出更高的催化活性，这归因于从光致发光研究中证实的减少的电荷复合。
