The quest for desirable two-dimensional (2D) materials and facile strategies to construct 2D layered composites with fascinating structures and compositions for high-performance electrocatalysis is still a major challenge. In the present research, novel nanocomposites of 2D zeolitic imidazolate framework-9 (ZIF-9) combined with Co-layered double hydroxide (Co LDH) were successfully synthetized through a controllable phase transition from ZIF-9(I). The 3D to 2D structural transformation of ZIF-9 was induced by deionized water, and the formation of 2D Co LDH was simultaneously realized during the one-step fabrication of ZIF-9(III)/Co LDH nanocomposites. Due to the high surface area, the presence of abundant metal sites, and the interactions between 2D ZIF-9(III) and 2D Co LDH, the as-optimized ZIF-9(III)/Co LDH nanocomposite exhibits great electrochemical activities for oxygen evolution reaction (OER) (η = 297 mV at 10 mA cm⁻²) in 1.0 M KOH solution. The electrochemical performance of the ZIF-9(III)/Co LDH nanocomposite was superior to those of the pure Co LDH, ZIF-9(III), and commercial RuO₂. The present work demonstrates that the proposed strategy can effectively boost catalytic activities and also design new routes to synthesize advanced MOF nanohybrids for various applications.

寻求理想的二维（2D）材料和简便的策略来构建具有引人入胜的结构和成分的2D层状复合材料以进行高性能电催化仍然是一项重大挑战。在本研究中，通过可控的ZIF-9（I）相变成功地合成了2D沸石咪唑酸酯骨架9（ZIF-9）与共层双氢氧化物（Co LDH）的新型纳米复合材料。用去离子水诱导ZIF-9的3D到2D结构转变，并在一步制备ZIF-9（III）/ Co LDH纳米复合材料的同时实现2D Co LDH的形成。由于高表面积，大量金属位点的存在以及2D ZIF-9（III）和2D Co LDH之间的相互作用，^-2）在1.0 M KOH溶液中。ZIF-9（III）/ Co LDH纳米复合材料的电化学性能优于纯Co LDH，ZIF-9（III）和商业RuO ₂的电化学性能。目前的工作表明，所提出的策略可以有效地提高催化活性，并设计新的途径来合成先进的MOF纳米杂物，以用于各种应用。