Graphene/LDHs hybrid composites synthesis and application in environmental protection

Layered double hydroxides (LDHs) and graphene-based nanomaterials show great application potential in environmental protection. The combination of LDHs and graphene materials has “win–win” and complementary advantages. Many studies have focused on synthesizing graphene/LDH hybrid composites (GLDH) to address the aggregation issue and improve the properties of individual components with unique synergistic properties including elevated surface area, numerous active sites, and superior electrical conductivity. In this review, the principal synthesis methodologies of GLDH are summarized. The development of GLDH as adsorbents and catalysts (in photocatalysis, advance oxidation processes, and catalytic reduction) for various pollutant (organic pollutants, heavy metals, and phosphate, among others) removal and other environmental applications (mainly as composite membranes, microbial fuel cells, and environmental sensors or for CO2 reduction and hazardous air pollutants oxidation, among others) are reviewed and discussed. Further research needs for the future application of GLDH involving environmental protection are also proposed.