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

Performance breakthrough of MoSe 2 ‐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 (PO 4 3− ) intercalation induced‐MoSe 2 (P‐MoSe 2 ) nanosheets on N‐doped mold spore carbon (N‐MSC) forming P‐MoSe 2 /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 MoSe 2 can be modulated by a simple phosphorization strategy to realize the conversion from 2H‐MoSe 2 to 1T‐MoSe 2 to produce biphase‐coexisted (1T‐2H)‐MoSe 2 by PO 4 3‐ intercalation (namely, P‐MoSe 2 ), 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‐MoSe 2 /N‐MSC with the help of density functional theory (DFT) calculation. Benefiting from these unique advantages, the P‐MoSe 2 /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‐MoSe 2 /N‐MSC and MoSe 2 /carbon nanosphere (MoSe 2 /CNS) counterparts. This work demonstrates a new kind of carbon material via biological cultivation, and simultaneously unravels the phase transformation mechanism of MoSe 2 by PO 4 3‐ intercalation.