The present invention relates to a process for the preparation of a boron phosphide, more specifically BP and/or B.sub.12P.sub.2, comprising the mechanochemical reaction of boron phosphate (BPO.sub.4) with at least one alkaline earth metal (EA). In particular, the process of the invention allows for the selective preparation of either BP or B.sub.12P.sub.2 with more than 95% purity, through the reduction of boron phosphate (BPO.sub.4) with at least one alkaline earth metal (EA) according to reaction (1) for BP and according to reaction (2) for B.sub.12P.sub.2: BPO.sub.4+4 EA.fwdarw.BP+4 EA(O) (1) 2BPO.sub.4+5 (EA)B.sub.2+3 EA.fwdarw.B.sub.12P.sub.2+8 EA(O) (2). The present invention further relates to boron phosphide powders, in particular BP or B.sub.12P.sub.2 powders, of nanometric or micrometric size.

A method that uses a pressurized reactive medium composed of inert solvents such as pressurized liquid or supercritical fluid carbon dioxide (C02), and sulfur hexafluoride (SF6) and reactive dissolved species ozone (03) and/or boron trifluoride (BF3) and general boron trihalogenides (BX3) to react with two-dimensional (2D) layered materials and thereby synthesize covalently oxygen and/or BX3 functionalized exfoliated 2D layered materials. When 2D layered materials are dispersed in these reactive liquids or fluids by ultrasound sonication or high shear mixing, a simultaneous covalent functionalization and exfoliation of the 2D layered materials happens. Following attainment of the required extent of functionalization and exfoliation, the unreacted 03, BX3, SF6 and C02 can be easily removed as gases by decompression leaving behind the solid phase, thereby leading to efficient and economical production of functionalized and exfoliated 2D layered materials.

The present invention concerns a process for the production of boron phosphide BP comprising the reduction of boron phosphate BPO.sub.4 with at least one alkaline earth metal (EA) according to Equation (1): BPO.sub.4+4 EA.fwdarw.BP+4 EA(O)(1).

The present invention relates to a process for the preparation of a boron phosphide, more specifically BP and/or B.sub.12P.sub.2, comprising the mechanochemical reaction of boron phosphate (BPO.sub.4) with at least one alkaline earth metal (EA). In particular, the process of the invention allows for the selective preparation of either BP or B.sub.12P.sub.2 with more than 95% purity, through the reduction of boron phosphate (BPO.sub.4) with at least one alkaline earth metal (EA) according to reaction (1) for BP and according to reaction (2) for B.sub.12P.sub.2: BPO.sub.4+4 EA->BP+4 EA(O) (1) 2BPO.sub.4+5 (EA)B.sub.2+3 EA->B.sub.12P.sub.2+8 EA(O) (2). The present invention further relates to boron phosphide powders, in particular BP or B.sub.12P.sub.2 powders, of nanometric or micrometric size.

A simplified method for synthesizing boron phosphide at high yields. The method requires mixing of boron phosphate and magnesium metal without diluents into a homogenous mixture, loosely packing the mixture at less than 20,000 psi and igniting the mixture using an energy input that is not greater than 20% of the reaction energy output to create a self-propagating high-temperature reaction wherein the boron phosphate and magnesium metal is completely burned during the reaction to synthesize boron phosphide at high yields.

A simplified method for synthesizing boron phosphide at high yields. The method requires mixing of boron phosphate and magnesium metal without diluents into a homogenous mixture, loosely packing the mixture at less than 20,000 psi and igniting the mixture using an energy input that is not greater than 20% of the reaction energy output to create a self-propagating high-temperature reaction wherein the boron phosphate and magnesium metal is completely burned during the reaction to synthesize boron phosphide at high yields.

The present invention concerns a process for the production of boron phosphide BP comprising the reduction of boron phosphate BPO.sub.4 with at least one alkaline earth metal (EA) according to Equation (1): BPO.sub.4+4 EA.fwdarw.BP4 EA(O)(1)