Coupled Biphase (1T‐2H)‐MoSe2 on Mold Spore Carbon for Advanced Hydrogen Evolution Reaction

Performance breakthrough of MoSe₂‐based hydrogen evolution reaction (HER) electrocatalysts largely relies on sophisticated phase modulation and judicious innovation on conductive matrix/support. In this work the controllable synthesis of phosphate ion (PO₄^3?) intercalation induced‐MoSe₂ (P‐MoSe₂) nanosheets on N‐doped mold spore carbon (N‐MSC) forming P‐MoSe₂/N‐MSC composite electrocatalysts is realized. Impressively, a novel conductive N‐MSC matrix is constructed by a facile mold fermentation method. Furthermore, the phase of MoSe₂ can be modulated by a simple phosphorization strategy to realize the conversion from 2H‐MoSe₂ to 1T‐MoSe₂ to produce biphase‐coexisted (1T‐2H)‐MoSe₂ by PO₄^3‐ intercalation (namely, P‐MoSe₂), confirmed by synchrotron radiation technology and spherical aberration‐corrected TEM (SACTEM). Notably, higher conductivity, lower bandgap and adsorption energy of H⁺ are verified for the P‐MoSe₂/N‐MSC with the help of density functional theory (DFT) calculation. Benefiting from these unique advantages, the P‐MoSe₂/N‐MSC composites show superior HER performance with a low Tafel slope (≈51 mV dec^‐1) and overpotential (≈126 mV at 10 mA cm^‐1) and excellent electrochemical stability, better than 2H‐MoSe₂/N‐MSC and MoSe₂/carbon nanosphere (MoSe₂/CNS) counterparts. This work demonstrates a new kind of carbon material via biological cultivation, and simultaneously unravels the phase transformation mechanism of MoSe₂ by PO₄^3‐ intercalation.