Superhard Phases of Simple Substances and Binary Compounds of the B-C-N-O System: from Diamond to the Latest Results (a Review)

TL;DR

This review discusses known and hypothetical superhard phases within the B-C-N-O system, focusing on their structures, properties, synthesis conditions, and methods for identification, highlighting recent advances and potential new materials.

Contribution

It provides a comprehensive overview of superhard phases in the B-C-N-O system, including recent synthesis conditions and characterization methods, summarizing current knowledge and future directions.

Findings

Descriptions of known and hypothetical superhard phases

Synthesis conditions at high pressures and temperatures

Methods for identifying and characterizing materials

Abstract

The basic known and hypothetic one- and two-element phases of the B-C-N-O system (both superhard phases having diamond and boron structures and precursors to synthesize them) are described. The attention has been given to the structure, basic mechanical properties, and methods to identify and characterize the materials. For some phases that have been recently described in the literature the synthesis conditions at high pressures and temperatures are indicated.