Ultrafast Intercalation Enabled by Strong Solvent-Host Interactions: Understanding Solvent Effect at the Atomic Level

Solvents play an essential role in many areas of chemistry and is the cornerstone of understanding reactivity in solution-phase reactions. Solvent effects have been widely observed in intercalation reactions; however, understanding of the influence of solvents on the thermodynamics and kinetics remains largely elusive in intercalation chemistry. Now, the solvent-dependent kinetics of ferrocene intercalation into a layered vanadyl phosphate (VOPO₄ ⋅2 H₂ O) host is presented, with a special focus on primary alcohols. From methanol to 1-hexnaol, the intercalation rate peaks in 1-propanol (80 times faster than the slowest case in methanol). Similar kinetics of exfoliation are also found in these solvents without ferrocene. The correlation between intercalation and exfoliation is understood at atomic level by DFT calculations, which reveal the role of pre-intercalated solvent molecules play in intralayer interactions, interlayer expansion, and layer sliding.