Enhancement of 1T‐MoS₂ Superambient Temperature Stability and Hydrogen Evolution Performance by Intercalating a Phenanthroline Monolayer

Abstract Metastable modification of MoS₂ (1T) is widely recognized as a hopeful non‐precious electrocatalyst in hydrogen production. This paper describes an approach to impart a superambient temperature stability to 1T‐MoS₂ by incorporating it in 2D hybrid architecture with cationic monomolecular phenanthrolinium (PhenH⁺) hydrate layers. The atomic structure and bonding interactions of the assembled architecture revealed by PXRD, TEM, XPS, Raman and UV‐Vis spectroscopy data coupled with DFT calculations and quantum theory of atoms in molecules (QTAIM) analysis suggest that the 1T‐MoS₂ sheets are involved in strong bonding with the PhenH‐H₂O layers. This results in a highly stable layered system, which is kept intact in 0.5 M sulfuric acid electrolyte and tolerates superambient temperature heating. As compared with pure 1T‐MoS₂, the compound with a phenanthroline interlayer provides greater activity and better current‐voltage efficiency in electrocatalytic hydrogen evolution after heating treatment owing to stabilization of the 1T phase. The obtained results could be useful for the design of novel electrocatalytic devices exploiting 1T‐MoS₂ modification.