Molybdenum diselenide (MoSe2), as a member of transitional metal chalcogenides (TMDs), is regarded as a promising electrocatalyst for hydrogen evolution reaction (HER). However, its intrinsic performance is still hampered by insufficient exposure of active sites and inferior electric conductivity. The phase‐engineered synthesis of stable metallic 1T‐MoSe2 with abundant active sites is thus highly desirable for further boosting HER performance. Herein, a phosphorus (P)‐doped MoSe2 with controlled 2H/1T heterophases is synthesized through a facile way. Combining calculations and experiments, it is demonstrated that the doping of P (≈0.83 wt%) not only induces a phase change from 2H to 1T, but activates the Se atoms in the basal plane, thereby significantly enhancing its intrinsic HER performance. An overpotential of 174 mV is achieved at the benchmark of 10 mA cm−2 with a Tafel slope of 51 mV dec−1. More importantly, after the long‐term run at 180 mV for 10 h, the P‐1T/2H‐MoSe2 still displays a high current density of 10.43 mA cm−2 and keeps its original 2H/1T heterostructures, showing superior electrochemical stability and structural robustness. This work provides a facile method for improving the intrinsic HER activity of MoSe2 through nonmetal doping, which helps to understand the activity origin of MoSe2.

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The nanoscale structure of catalysts has a profound influence on their physicochemical properties. However, the controlled synthesis of desired highly active microstructures is still challenging. In this work, through the introduction of phytic acid (PA), MoSe 2 nanosheets with 2H/3R heterophases are successfully synthesized on a P-doped carbon substrate. Plenty of defects are introduced into the basal plane of MoSe 2 with largely expanded interlayer spacings, which increase the number of active sites and enhance the electronic/ionic transport and mass transfer. Benefiting from these structure merits, the obtained heterostructure exhibits superior HER activity and durability. A low overpotential of 164 mV is observed at a current density of 10 mA cm −2 with a Tafel slope of 44 mV dec −1 . The HER performance is well maintained even after 10 h tests, showing superior electrochemical robustness. This controlled synthesis 2H/3R heterophased MoSe 2 can be extended to other transitional metal chalcogenides (TMDs) for diverse applications.

In this work, MoS-based hybrid tubular nanostructures are facilely synthesized via a self-assembly-assisted process and evaluated as a bifunctional electrocatalyst for hydrogen evolution reactions (HERs) and oxygen reduction reactions (ORRs). By simply mixing the reactants under ambient conditions, (NH)MoS/polydopamine (PDA) hybrid nanospheres are formed. The protonated dopamine is linked to tetrahedral [MoS] via weak N-H···S and O-H···S interactions, causing the PDA nanospheres merging together and forming nanorods under stirring-induced shear force. Moreover, the oxidative polymerization of dopamine proceeds on the surface of the nanorods, whereas it is prohibited inside the nanorods owing to lack of oxygen, leading to outward diffusion of dopamine and hence cavitation. After annealing, the tubular morphology is perfectly retained, while ultrafine MoS monolayers are formed due to the confinement of the framework. Benefiting from these unique structural features, the MoS/C hybrid nanotubes possess abundant active sites and high surface area, as well as boost electronic and ionic transport, remarkably enhancing their electrocatalytic activities. The onset and half-wave potentials are 0.91 and 0.82 V, respectively, for ORR, close to those of Pt/C. Moreover, low onset potential and small Tafel slope are also observed for HER, demonstrating the potential of the hybrid nanotubes as a promising non-noble metal bifunctional electrocatalyst.

An organocatalytic asymmetric C3-allylic alkylation of indolone-2-imines with MBH carbonates has been developed for the first time. As opposed to previous reports, an "interrupted" annulation was achieved, affording 3-allylindoles in generally high yields with excellent stereoselectivities. The representative scale-up reaction and transformation of 3-allylindoles were examined. A possible mechanism was also proposed.