Graphene derivatives containing covalently bound halogens (graphene halides) represent promising two-dimensional systems having interesting physical and chemical properties. The attachment of halogen atoms to sp² carbons changes the hybridization state to sp³, which has a principal impact on electronic properties and local structure of the material. The fully fluorinated graphene derivative, fluorographene (graphene fluoride, C₁F₁), is the thinnest insulator and the only stable stoichiometric graphene halide (C₁X₁). In this review, we discuss structural properties, syntheses, chemistry, stabilities, and electronic properties of fluorographene and other partially fluorinated, chlorinated, and brominated graphenes. Remarkable optical, mechanical, vibrational, thermodynamic, and conductivity properties of graphene halides are also explored as well as the properties of rare structures including multilayered fluorinated graphenes, iodine-doped graphene, and mixed graphene halides. Finally, patterned halogenation is presented as an interesting approach for generating materials with applications in the field of graphene-based electronic devices.

Layered silicates provide an interesting avenue to novel materials. There has been a growing interest in recent years for the development of functional materials using tailor made clays. This review highlights one such tailor made, water dispersible aminopropyl functionalized magnesium phyllosilicate (aminoclay) of the type R₈Si₈Mg₆O₁₆(OH)₄, (where R = –CH₂CH₂NH₂) and its multiple applications in catalysis, biology, fuel cells and light-harvesting hybrids.