Vacancy-Rich Sn-P-I Catalyst for Highly Efficient Black Phosphorus Preparation and Catalytic Mechanistic Investigation

Abstract

Black phosphorus (BP) possesses unique physicochemical properties with broad application potential, but its synthesis is hindered by high reaction temperatures and long reaction times. The underlying mechanisms of BP growth remain unclear. In this work, we utilized white phosphorus (WP) as precursor for efficient synthesis of BP, employing P-vacancy-rich Sn-P-I clathrate as catalyst. The catalytic mechanism of Sn-P-I clathrate was systematically investigated, revealing its critical role in dissociating P₄ molecules into P₂ molecules and inducing their structural reconstruction to form BP. The catalytic activity of Sn-P-I clathrate was found to be strongly correlated with its phosphorus vacancy content. DFT calculations indicate that the P-vacancy-containing Sn-P-I clathrate tend to undergoes dynamic structural reconstruction, which reduces the reaction barrier for BP growth. Notably, BP growth using WP can occur at temperatures as low as 420°C, significantly lower than using red phosphorus (RP) as precursor. The total preparation time for BP was reduced from at least a dozen hours to 90 minutes with a high yield of 95.5%, representing the shortest reaction time reported to date.