The subject of the invention is the development of a new process for producing phosphorus P4 from phosphoric acid. In this process, the phosphoric acid and a hydrophilic source of carbon and of hydrogen (biomass, kerogen, “STEP” purification plant sludge, organic polymer) are mixed, and the mixture is treated at a temperature of 80 to 150° C. in order to ensure grafting of the phosphates on the carbon backbone. The production of the phosphorus P4 is carried out by heat treatment of the precursor at a temperature at which phosphorus is produced. The temperature range is from 550° C. to 950° C. This process can be carried out at temperatures below those of conventional phosphorus production without the occurrence of the production of solid by-products normally formed in conventional phosphorus production. The process can be used to produce phosphoric acid for food or medical use.

The subject of the invention is the development of a new process for producing phosphorus P4 from phosphoric acid. In this process, the phosphoric acid and a hydrophilic source of carbon and of hydrogen (biomass, kerogen, “STEP” purification plant sludge, organic polymer) are mixed, and the mixture is treated at a temperature of 80 to 150° C. in order to ensure grafting of the phosphates on the carbon backbone. The production of the phosphorus P4 is carried out by heat treatment of the precursor at a temperature at which phosphorus is produced. The temperature range is from 550° C. to 950° C. This process can be carried out at temperatures below those of conventional phosphorus production without the occurrence of the production of solid by-products normally formed in conventional phosphorus production. The process can be used to produce phosphoric acid for food or medical use.

A scalable approach for the synthesis of black phosphorus (BP) material thin films over large areas is described. A red phosphorus (RP) material thin film may be deposited on a substrate followed by conversion to a BP material thin film using high-pressure alone or high pressure and high temperature. A thin-film of dielectric material such as hexagonal boron nitride (hBN) can be formed on a RP material film before the conversion is performed to improve the crystalline quality and stability of the converted BP material. Surprisingly, an atomically sharp and defect-free interface can be formed between the converted BP material and hBN. The BP material has high crystalline uniformity and can be used to fabricate thin-film transistors and optoelectronic devices such as infrared photodetectors.

A scalable approach for the synthesis of black phosphorus (BP) material thin films over large areas is described. A red phosphorus (RP) material thin film may be deposited on a substrate followed by conversion to a BP material thin film using high-pressure alone or high pressure and high temperature. A thin-film of dielectric material such as hexagonal boron nitride (hBN) can be formed on a RP material film before the conversion is performed to improve the crystalline quality and stability of the converted BP material. Surprisingly, an atomically sharp and defect-free interface can be formed between the converted BP material and hBN. The BP material has high crystalline uniformity and can be used to fabricate thin-film transistors and optoelectronic devices such as infrared photodetectors.

A scalable approach for the synthesis of black phosphorus (BP) material thin films over large areas is described. A red phosphorus (RP) material thin film may be deposited on a substrate followed by conversion to a BP material thin film using high-pressure alone or high pressure and high temperature. A thin-film of dielectric material such as hexagonal boron nitride (hBN) can be formed on a RP material film before the conversion is performed to improve the crystalline quality and stability of the converted BP material. Surprisingly, an atomically sharp and defect-free interface can be formed between the converted BP material and hBN. The BP material has high crystalline uniformity and can be used to fabricate thin-film transistors and optoelectronic devices such as infrared photodetectors.

A scalable approach for the synthesis of black phosphorus (BP) material thin films over large areas is described. A red phosphorus (RP) material thin film may be deposited on a substrate followed by conversion to a BP material thin film using high-pressure alone or high pressure and high temperature. A thin-film of dielectric material such as hexagonal boron nitride (hBN) can be formed on a RP material film before the conversion is performed to improve the crystalline quality and stability of the converted BP material. Surprisingly, an atomically sharp and defect-free interface can be formed between the converted BP material and hBN. The BP material has high crystalline uniformity and can be used to fabricate thin-film transistors and optoelectronic devices such as infrared photodetectors.