Boron monoxide

Boron monoxide (BO) is a binary compound of boron and oxygen. It has a molar mass of 26.81 g/mol. The material was first reported in 1940, with a modified synthetic procedure published in 1955, however, the material's structure had remained unknown for nearly a century. A number of allotropes of BO have been theorized ranging from molecular species, to 1D, 2D, and 3D-structured materials, but these were difficult to differentiate using common structural characterization methods. Recent work suggests that the material forms 2D nanosheets composed of O-bridged B₄O₂ rings, a structure initially postulated in 1961. Due to the lack of precise structural information on the identity of the compound, it has not found widespread use in industry.