BSTRACTOrganic–inorganic metal halide hybrids have emerged as new generation functional materials with exceptional structure and property tunability for a variety of applications. Besides the most investigated ABX
3
metal halide perovskites
a variety of hybrids consisting of a wide range of organic cations and metal halide anions have been developed and studied recently. Here
we provide an overview of these new materials possessing various crystallographic structures
including double perovskites
low dimensional hybrids
and other perovskite-related materials. We discuss their syntheses
functional properties
and optoelectronic applications. Challenges and opportunities are then laid out for these hybrid materials beyond perovskites.