3D hierarchical and porous layered double hydroxide structures: an overview of synthesis methods and applications

Nanostructured layered double hydroxide (LDH) materials with unique diffusion properties, large surface area along with desired functionalities have recently been produced for a number of well-established and advanced fields of applications. In this review, we describe and discuss the main synthetic methods that have been reported for the fabrication of porous LDH with tailored chemical composition and porosity. The efficiency of soft and hard templating approaches is particularly reviewed. A special emphasis is put on the microstructure and porosity of the materials according to the synthetic method involved. Finally, the performance enhancement of the materials due to the presence of porosity, especially macroporosity, in applications such as pollutant removal, catalysis and energy storage and conversion is overviewed.