In a world with rising concern about energy security, environmental crisis, and global warming, exploring superior catalysts for oxygen evolution reaction, super capacitor, and the treatment of pollutant ions in waste water are getting more and more attention. Layered double hydroxide (LDH) has many properties such as memory effect, nice catalysis ability, anion exchange, acid-base and thermal stability, which has been widely concerned in various fields to solve the above problems. LDH has excellent performance for oxygen evolution electrocatalysis, low cost, adjustable structure. The intercalation reaction can be carried out between layers of LDH. However, the poor electron conductivity of LDH reduces its electrochemical performance. Moreover, the LDH layers are easy to agglomerate in the synthesis process, resulting low conductivity and low catalytic activity. These problems can be solved by improving the synthesis method of LDH and compounding LDH with various functional materials. In recent years, in order to improve the conductivity of LDH, researchers have in situ grown LDH on various conductive substrate, which can expose more active sites and as a result improve the catalytic activity of LDHs. By compounding LDH with graphene, the specific capacitance, conductivity and cycle stability of LDH/graphene composites can be enhanced, and the adsorption capacity of LDH for CO2 can also be improved, making LDH widely used to solve energy crisis and environmental pollution problems. This article reviews the synthesis methods of LDH and LDH composites, and summarizes the applications of LDH and its composites in catalysis, energy storage, and environmental protection in recent years. First, the application of LDH in electrocatalytic water oxidation and photocatalysis is introduced, and then the application of LDH materials in supercapacitors and environmental problems such as water pollution treatment is described. © 2021, Materials Review Magazine. All right reserved.
