Yi Wendi, Jiang Haoqing, Cheng Gary J
The Institute of Technological Sciences, Wuhan University, Wuhan, Hubei, 430072, China.
Hubei Yangtze Memory Laboratories, Wuhan, Hubei, 430205, China.
Small. 2022 Sep;18(35):e2202403. doi: 10.1002/smll.202202403. Epub 2022 Aug 7.
Laser is a powerful tool for the synthesis of nanomaterials. The intensive laser pulses delivered to materials within nanoseconds allow the formation of novel structures that are inaccessible for conventional methods. Layered double hydroxide (LDH) nanostructures with high porosity, suitable dopants, and rich defects are desirable for catalysts, however, tremendously difficult in a one-pot synthesis. Here it is found that confined laser shock in solvent leads to the formation of nanoreactors which guide the assembly of multiscale LDH building units, larger nanosheets as frame and smaller nanodomains as building blocks. These nanodomains have rich vacancy defects and are interlocked in a high packed density of 10 cm , leaving rich mesopores across the nanosheets and coral-like morphology. Like the natural coral reef that has multiscale structure to accommodate different marine organisms, the coral-like LDH metastructure provides large surface area and rich active sites for the interaction with guest molecules. Benefiting from the multiscale porous structure and rational dopant, this LDH catalyst exhibits a low overpotential of 220 mV at 10 mA cm for oxygen evolution reaction (OER), standing as one of the best LDH catalysts to date.
激光是合成纳米材料的有力工具。在纳秒内传递到材料的高强度激光脉冲能够形成传统方法无法获得的新型结构。具有高孔隙率、合适的掺杂剂和丰富缺陷的层状双氢氧化物（LDH）纳米结构对催化剂来说是理想的，然而，在一锅法合成中极其困难。在此发现，溶剂中的受限激光冲击导致形成纳米反应器，其引导多尺度LDH构建单元的组装，较大的纳米片作为框架，较小的纳米域作为构建块。这些纳米域具有丰富的空位缺陷，以10厘米的高堆积密度互锁，在纳米片上留下丰富的介孔和珊瑚状形态。就像具有多尺度结构以容纳不同海洋生物的天然珊瑚礁一样，珊瑚状LDH亚结构为与客体分子的相互作用提供了大表面积和丰富的活性位点。受益于多尺度多孔结构和合理的掺杂剂，这种LDH催化剂在10 mA cm下的析氧反应（OER）过电位低至220 mV，是迄今为止最好的LDH催化剂之一。
