Zhou Li-Jing, Huang Xiaoxi, Chen Hui, Jin Panpan, Li Guo-Dong, Zou Xiaoxin
State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, International Joint Research Laboratory of Nano-Micro Architecture Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, China.
Dalton Trans. 2015 Jul 7;44(25):11592-600. doi: 10.1039/c5dt01474c.
Layered double hydroxide has been used in a variety of areas, including but not limited to catalysis, energy storage, drug or gene delivery, water treatment, etc. Herein, we report a new simple hydrothermal method to prepare a high surface area flower-like Ni-Fe layered double hydroxide (LDH) assembled by nanosheets by using nickel alkoxide and FeSO4 as the only starting materials. It is free of alkaline solution and other additives for directing or supporting in the synthesis procedure. The formation mechanism of this flower-like LDH formed by ultrathin nanosheets is also discussed. Moreover, the as-obtained LDH material shows increased electrocatalytic activity and stability toward WOR in alkaline media compared with the materials prepared without a Ni alkoxide precursor or Fe precursor, namely α-Fe2O3 and Ni(OH)2, respectively. In addition, the electrocatalytic activity is demonstrated to be related to the molar ratio of Fe and Ni in the final Ni-Fe material, and the best activity is achieved when the ratio reaches 0.52 : 1. The phase compositions of the resulting Ni-Fe(x) are discussed. Furthermore, the Ni-Fe LDH material reported herein might be employed as a promising noble-metal-free water oxidation catalyst to replace the IrOx material-the state-of-the-art water oxidation catalyst.
层状双氢氧化物已被应用于各种领域，包括但不限于催化、能量存储、药物或基因递送、水处理等。在此，我们报道了一种新的简单水热法，以醇盐镍和硫酸亚铁作为唯一的起始原料，制备由纳米片组装而成的高比表面积花状镍铁层状双氢氧化物（LDH）。在合成过程中无需碱性溶液和其他用于导向或支撑的添加剂。还讨论了由超薄纳米片形成这种花状LDH的形成机理。此外，与分别不使用醇盐镍前驱体或铁前驱体制备的材料（即α-Fe₂O₃和Ni(OH)₂）相比，所获得的LDH材料在碱性介质中对析氧反应显示出更高的电催化活性和稳定性。此外，电催化活性被证明与最终镍铁材料中Fe和Ni的摩尔比有关，当该比例达到0.52∶1时可实现最佳活性。讨论了所得Ni-Fe(x)的相组成。此外，本文报道的镍铁LDH材料有望作为一种有前景的无贵金属析氧催化剂，以替代目前最先进的析氧催化剂IrOx材料。
