Research Progress on Layered Double Hydroxides and Their Derivatives toward Solar-to-Chemical Energy Conversion

The energy crisis, along with environmental deterioration and climate change caused by fossil fuel combustion, has propelled scientific and technological developments for versatile renewable energy applications. As a green technology, photocatalysis enables the conversion of abundant solar energy into useful chemical energy, in which advanced photocatalysts play a crucial role. Among various photocatalysts, layered double hydroxides (LDHs), a class of two-dimensional (2D) materials, and their derivatives, such as mixed metal oxide (MMO) and spinel, have attracted considerable attention in solar energy conversion. This review summarizes the recent achievements of LDHs and their derivatives used in photocatalysis. First, the LDHs, MMO, and spinel photocatalysts are briefly introduced. Next, the advanced strategies of structure modulation for photocatalytic properties are systematically elaborated. Then, the photocatalytic performance of LDHs and their derivatives is described concerning their applications in photocatalysis, including water splitting, CO₂ reduction, and N₂ fixation. Finally, the challenges and opportunities for the future development of this fast-growing area are presented and thoroughly discussed.