Solid-State Investigation, Storage, and Separation of Pyrophoric PH₃ and P₂ H₄ with α-Mg Formate

Phosphane, PH₃ -a highly pyrophoric and toxic gas-is frequently contaminated with H₂ and P₂ H₄ , which makes its handling even more dangerous. The inexpensive metal-organic framework (MOF) magnesium formate, α-[Mg(O₂ CH)₂ ], can adsorb up to 10 wt % of PH₃ . The PH₃ -loaded MOF, PH₃ @α-[Mg(O₂ CH)₂ ], is a non-pyrophoric, recoverable material that even allows brief handling in air, thereby minimizing the hazards associated with the handling and transport of phosphane. α-[Mg(O₂ CH)₂ ] further plays a critical role in purifying PH₃ from H₂ and P₂ H₄ : at 25 °C, H₂ passes through the MOF channels without adsorption, whereas PH₃ adsorbs readily and only slowly desorbs under a flow of inert gas (complete desorption time≈6 h). Diphosphane, P₂ H₄ , is strongly adsorbed and trapped within the MOF for at least 4 months. P₂ H₄ @α-[Mg(O₂ CH)₂ ] itself is not pyrophoric and is air- and light-stable at room temperature.