Nitrogen trifluoride

Nitrogen trifluoride (NF3) is an inorganic, colorless, non-flammable, toxic gas with a slightly musty odor. It finds increasing use within the manufacturing of flat-panel displays, photovoltaics, LEDs and other microelectronics. Nitrogen trifluoride is also an extremely strong and long-lived greenhouse gas. Its atmospheric burden exceeded 2 parts per trillion during 2019 and has doubled every five years since the late 20th century. Nitrogen trifluoride did not exist in significant quantities on Earth prior to its synthesis by humans. It is a rare example of a binary fluoride that can be prepared directly from the elements only at very uncommon conditions, such as an electric discharge. After first attempting the synthesis in 1903, Otto Ruff prepared nitrogen trifluoride by the electrolysis of a molten mixture of ammonium fluoride and hydrogen fluoride. It proved to be far less reactive than the other nitrogen trihalides nitrogen trichloride, nitrogen tribromide and nitrogen triiodide, all of which are explosive. Alone among the nitrogen trihalides it has a negative enthalpy of formation. It is prepared in modern times both by direct reaction of ammonia and fluorine and by a variation of Ruff's method. It is supplied in pressurized cylinders. NF3 is slightly soluble in water without undergoing chemical reaction. It is nonbasic with a low dipole moment of 0.2340 D. By contrast, ammonia is basic and highly polar (1.47 D). This difference arises from the fluorine atoms acting as electron-withdrawing groups, attracting essentially all of the lone pair electrons on the nitrogen atom. NF3 is a potent yet sluggish oxidizer. It oxidizes hydrogen chloride to chlorine: 2 NF3 + 6 HCl → 6 HF + N2 + 3 Cl2 It is compatible with steel and Monel, as well as several plastics. It converts to tetrafluorohydrazine upon contact with metals, but only at high temperatures: 2 NF3 + Cu → N2F4 + CuF2 NF3 reacts with fluorine and antimony pentafluoride to give the tetrafluoroammonium salt: NF3 + F2 + SbF5 → NFSbF Mixtures of NF3 and B2H6 are explosive even at cryogenic temperatures, reacting to produce nitrogen gas, boron trifluoride, and hydrofluoric acid.

Aerosol acidity and liquid water content regulate the dry deposition of inorganic reactive nitrogen

Athanasios Nenes, Spyros Pandis

Ecosystem productivity is strongly modulated by the atmospheric deposition of inorganic reactive nitrogen (the sum of ammonium and nitrate). The individual contributions of ammonium and nitrate vary considerably over space and time, giving rise to complex ...

COPERNICUS GESELLSCHAFT MBH2021

Unexpectedly minor nitrous oxide emissions from fluvial networks draining permafrost catchments of the East Qinghai-Tibet Plateau

Aerosol acidity and liquid water content regulate the dry deposition of inorganic reactive nitrogen

Co-culture of microalgae and bacteria for wastewater treatment

Aerosol acidity and liquid water content regulate the dry deposition of inorganic reactive nitrogen

Co-culture of microalgae and bacteria for wastewater treatment

Unexpectedly minor nitrous oxide emissions from fluvial networks draining permafrost catchments of the East Qinghai-Tibet Plateau