(1) 3D structures can producea relatively high specific surface area and/or unique hierarchical porous 3D architectures; (2) the highly oriented and rigid3D architecture can help overcome the problem of lowconductivity in conventional LDHs; (3) many 3D LDHs arecomposed of thin LDH nanosheets; (4) 3D LDHs may havehigher surface activity than common 2D LDH