Yang Liuqing, Huang Jianfeng, Cao Liyun, Shi Li, Yu Qing, Kong Xingang, Jie Yanni
School of Materials Science and Engineering, Shaanxi University of Science and Technology, Weiyang, Xi'an, Shaanxi 710021, P.R. China.
Environmental Remediation Materials Unit, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
Sci Rep. 2016 Jun 16;6:27765. doi: 10.1038/srep27765.
Sb4O5Cl2 hollow microspheres with self-narrowed bandgap and optimized photocatalytic performances are synthesized via a facile template-free method. It is found that the crystal structure and morphology of Sb4O5Cl2 crystallites are strongly dependent on the pH values of precursors. Nano-sized irregular-cuboids assembled Sb4O5Cl2 micro-particles and hollow microspheres can be synthesized at pH 1 and 2, whereas individual Sb4O5Cl2 micro-belts become to form when the pH is higher than 3. The irregular-cuboids assembled Sb4O5Cl2 micro-particles and hollow microspheres exhibit self-narrowed bandgap and higher light absorption ability compared with individual Sb4O5Cl2 micro-belts. The photoelectrochemical measurements show that the assembled Sb4O5Cl2 hollow microsphere crystallites prepared at pH 2 exhibit enhanced carrier density, improved separation efficiency of electron-hole pairs and decreased electron-transfer resistance. As a result, the irregular-cuboids assembled Sb4O5Cl2 hollow microspheres prepared at pH = 2 exhibit the highest photocatalytic activity for the degradation of gaseous iso-propanol (IPA) and Rhodamine B (RhB) aqueous solution. The good photocatalytic activity of Sb4O5Cl2 sample prepared at pH = 2 may be caused by the synergistic effect of its higher light absorption, the decreased electron-transfer resistance, the suppressed recombination of photogenerated electrons and holes, and the increased surface area.
通过一种简便的无模板方法合成了具有自窄带隙和优化光催化性能的Sb4O5Cl2空心微球。发现Sb4O5Cl2微晶的晶体结构和形貌强烈依赖于前驱体的pH值。在pH值为1和2时，可以合成纳米尺寸的不规则长方体组装的Sb4O5Cl2微粒和空心微球，而当pH值高于3时，会形成单个的Sb4O5Cl2微带。与单个的Sb4O5Cl2微带相比，不规则长方体组装的Sb4O5Cl2微粒和空心微球表现出自窄带隙和更高的光吸收能力。光电化学测量表明，在pH值为2时制备的组装Sb4O5Cl2空心微球微晶表现出增强的载流子密度、改善的电子-空穴对分离效率和降低的电子转移电阻。结果，在pH = 2时制备的不规则长方体组装的Sb4O5Cl2空心微球对气态异丙醇（IPA）和罗丹明B（RhB）水溶液的降解表现出最高的光催化活性。在pH = 2时制备的Sb4O5Cl2样品的良好光催化活性可能是由于其较高的光吸收、降低的电子转移电阻、抑制的光生电子和空穴的复合以及增加的表面积的协同效应。
