In situ fabrication of a Ni–Fe–S hollow hierarchical sphere: an efficient (pre)catalyst for OER and HER

Abstract

Designing low-cost, highly active and stable electrocatalysts is very important to various renewable energy storage and conversion devices. We fabricated a hierarchically porous Ni-Fe-S hollow hierarchical sphere through a solvothermal...

Fe–Ni–Co trimetallic oxide hierarchical nanospheres as high-performance bifunctional electrocatalysts for water electrolysis

“…We discovered that mixed metal complexes have substantially bigger HER electrochemically active surface areas than single-metal-based catalysts as a result of this finding. 49 The TOF values for the HER electrocatalysts can be calculated using the following equation to gain insight into the intrinsic HER activity:TOF = ( J × A )/(2 × n × F )where J is the OER current density, A is the surface area of the anode, and F is the Faraday constant. As shown in Fig.…”

Rough Ni@MoN corals for the hydrogen evolution reaction in acidic and alkaline media

“…This indicates the faster ionic transport in Ni@MoN-700, thus facilitating an improvement of the HER kinetics. 12,38 The ECSA of a catalyst played a vital role in its HER catalytic activity. ECSA was in direct proportion to the double-layer capacitance (C dl ) obtained by measuring cyclic voltammetry (CV) curves in a non-faradaic potential region (Fig.…”

“…This indicates the faster ionic transport in Ni@MoN-700, thus facilitating an improvement of the HER kinetics. 12,38…”

Bimetallic Ni–Mo nitride@N-doped C as highly active and stable bifunctional electrocatalysts for full water splitting

“…Furthermore, the NiMoN-2 catalyst shows comparable OER activity to the state-of-the-art OER catalysts reported recently, such as Co-NiMoN-400, 6 Ni-Fe-MoN NTs, 18 and NiMoNS 32 (summarized in Table S2, ESI †). 6,[17][18][19][20]25,27,32,36,44,46,47 After 1 h of long-term electrolysis for the OER in an alkaline medium, the chemical structures and valence states of the internal appearance of NiMoN-2 were characterized to evaluate the durability and stability. As shown in Fig.…”

“…These experimental methods have complex conditions and are not conducive to large-scale application. [15][16][17][18][19][20] Here, we report a simple method to synthesize bimetallic Ni-Mo nitrides as bifunctional electrocatalysts for the total water decomposition process by urea grinding and ammonia annealing. To drive a current density of 10 mA cm À2 , NiMoN-2 requires an overpotential of 202 mV for the OER and 191 mV for the HER.…”