Ultrathin Transition Metal Dichalcogenide/3d Metal Hydroxide Hybridized Nanosheets to Enhance Hydrogen Evolution Activity

Abstract

The vast majority of the reported hydrogen evolution reaction (HER) electrocatalysts perform poorly under alkaline conditions due to the sluggish water dissociation kinetics. Herein, a hybridization catalyst construction concept is presented to dramatically enhance the alkaline HER activities of catalysts based on 2D transition metal dichalcogenides (TMDs) (MoS and WS ). A series of ultrathin 2D-hybrids are synthesized via facile controllable growth of 3d metal (Ni, Co, Fe, Mn) hydroxides on the monolayer 2D-TMD nanosheets. The resultant Ni(OH) and Co(OH) hybridized ultrathin MoS and WS nanosheet catalysts exhibit significantly enhanced alkaline HER activity and stability compared to their bare counterparts. The 2D-MoS /Co(OH) hybrid achieves an extremely low overpotential of ≈128 mV at 10 mA cm in 1 m KOH. The combined theoretical and experimental studies confirm that the formation of the heterostructured boundaries by suitable hybridization of the TMD and 3d metal hydroxides is responsible for the improved alkaline HER activities because of the enhanced water dissociation step and lowers the corresponding kinetic energy barrier by the hybridized 3d metal hydroxides.

Ultrafine Cobalt‐Doped Iron Disulfide Nanoparticles in Ordered Mesoporous Carbon for Efficient Hydrogen Evolution

“…According to previous studies, the doping of Co could elevate the Fermi energy of FeS 2 . With the increase of Fermi energy, the local work function on the catalyst surface decreases, which promotes the electron transfer from the catalyst surface to H. [11,[40][41][42][43] Surface wetting state of an electrode is important to catalytic process. [44] Therefore, we evaluated surface wettability of the electrodes towards water.…”

Tuning Interfacial Structures for Better Catalysis of Water Electrolysis

“…Various hetero-materials (Pt/Ni oxide, [41,88] metal/metal oxide, [39,89] metal/metal sulphide, [90] etc. [91] )f or the HER have also been demonstrated to follow such am echanism.…”

Boosting Alkaline Hydrogen Evolution Electrocatalysis over Metallic Nickel Sites through Synergistic Coupling with Vanadium Sesquioxide

“…and TMD (e.g., MoS 2 , WS 2 , etc.) . Notably, the metal−OH bond strength for V is larger than that for other transition metals .…”

“…and TMD (e.g., MoS 2 ,W S 2 ,e tc.). [26] Notably,t he metalÀOH bond strength for V is larger than that for other transition metals. [27] Moreover, compared with the single-component counterparts, the interface of the hybrids offered al ower energy pathway to cleave the HÀOH bond.…”