Strongly Coupled Molybdenum Carbide on Carbon Sheets as a Bifunctional Electrocatalyst for Overall Water Splitting

Abstract

High-performance and affordable electrocatalysts from earth-abundant elements are desirably pursued for water splitting involving hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Here, a bifunctional electrocatalyst of highly crystalline Mo C nanoparticles supported on carbon sheets (Mo C/CS) was designed toward overall water splitting. Owing to the highly active catalytic nature of Mo C nanoparticles, the high surface area of carbon sheets and efficient charge transfer in the strongly coupled composite, the designed catalysts show excellent bifunctional behavior with an onset potential of -60 mV for HER and an overpotential of 320 mV to achieve a current density of 10 mA cm for OER in 1 m KOH while maintaining robust stability. Moreover, the electrolysis cell using the catalyst only requires a low cell voltage of 1.73 V to achieve a current density of 10 mA cm and maintains the activity for more than 100 h when employing the Mo C/CS catalyst as both anode and cathode electrodes. Such high performance makes Mo C/CS a promising electrocatalyst for practical hydrogen production from water splitting.

Ni Strongly Coupled with Mo2C Encapsulated in Nitrogen‐Doped Carbon Nanofibers as Robust Bifunctional Catalyst for Overall Water Splitting

“…Nevertheless, Ni nanoparticles are prone to aggregation under typical HER and OER conditions, such as strong acid and alkali, and are prone to be corroded and passivated. [38][39][40][41][42] For instance, Kwak et al has successfully prepared Mo 2 C/carbon nanotube composites as bifunctional catalysts for both ORR and OER. [24][25][26][27] Among them, molybdenum carbide (Mo 2 C) is interesting due to its innocuous preparation process, large pH stability, and equivalent d-band electronic structure to Pt-group metals, [28][29][30][31] demonstrating a It is urgently required to develop highly efficient and stable bifunctional non-noble metal electrocatalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) for water splitting.…”

“…[24][25][26][27] Among them, molybdenum carbide (Mo 2 C) is interesting due to its innocuous preparation process, large pH stability, and equivalent d-band electronic structure to Pt-group metals, [28][29][30][31] demonstrating a It is urgently required to develop highly efficient and stable bifunctional non-noble metal electrocatalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) for water splitting. [39] Based on the abovementioned concepts, it is worth trying to achieve the whole water splitting through the synergistic effect between Ni and Mo 2 C electrocatalysts. Owing to the strong hydrogen binding energy on Mo 2 C and high electrical conductivity of Ni, synergetic effect between Ni and Mo 2 C nanoparticles significantly promote both HER and OER activities.…”

An Intriguing Pea‐Like Nanostructure of Cobalt Phosphide on Molybdenum Carbide Incorporated Nitrogen‐Doped Carbon Nanosheets for Efficient Electrochemical Water Splitting

“…[13,14] In addition, the presence of Co 2 + species in the materiali sa lso confirmed from the XPS study. [13,14] In addition, the presence of Co 2 + species in the materiali sa lso confirmed from the XPS study.…”

“…[9] Moreover,t he peak for P2pa t1 29.4 eV is presentf or the metal phosphide, and its exposure to the air forms PÀO( 133.4 eV), which is also detectable in the hybrid material. [13,34] Upon deconvolution, the sharp N1sX PS results indicatet he possible formation of pyridinic (398.7 eV), pyrrolic (400.2 eV), and graphitic (401.5 eV)nitrogen species, which clearlyd emonstrate significant nitrogen doping of the prepared carbon matrix. [13,34] Upon deconvolution, the sharp N1sX PS results indicatet he possible formation of pyridinic (398.7 eV), pyrrolic (400.2 eV), and graphitic (401.5 eV)nitrogen species, which clearlyd emonstrate significant nitrogen doping of the prepared carbon matrix.…”

“…[3][4][5] Among the family of metal carbides, molybdenumc arbide (Mo 2 C) is one of the best HER catalysts because the introduction of carbon into the interstitial position of molybdenum leads to modified d-band structures, similart ot hose of platinum, and its corrosion-resistance properties are expectedt ol ead to significant durability of the electrocatalyst. [13,14] On the other hand, metallic phosphides, and specifically cobalt phosphide (CoP), have af avorable hydrogen bindinge nergy (DE H* ), which is an important parameter for good HER performance. [13,14] On the other hand, metallic phosphides, and specifically cobalt phosphide (CoP), have af avorable hydrogen bindinge nergy (DE H* ), which is an important parameter for good HER performance.…”