Metal–organic framework (MOF)-derived plate-shaped CoS_1.097 nanoparticles for an improved hydrogen evolution reaction

Abstract

Metal-organic framework (MOF) derived transition metal sulfides are viewed as the reliable, cost-effective and alternative hydrogen evolution reaction (HER) efficient electrocatalyst that has been used to replace platinum and their...

A phase-engineered nickel sulfide and phosphide (NiS–Ni2P) heterostructure for enhanced hydrogen evolution performance supported with DFT analysis

“…The measured potential with respect to the saturated Ag/AgCl electrode is calibrated to the reversible hydrogen electrode (RHE) by following the Nernst equation: 8,57 E RHE = E (Ag/AgCl) + 0.0591 (pH) + 0.21 V. The Tafel slope values were calculated by using the Tafel equation as follows: η = a + b log J , the term named ( η : overpotential), ( a : Tafel constant), ( b : Tafel slope) and ( J : current density), respectively. 7,23 The presented polarization curves were iR -corrected (“ i ” is current and “ R ” represents solution resistance). Nyquist impedance analysis was verified at a potential of −0.23 V ( vs. RHE), and the supply scanning frequency scale was 1 MHz to 0.1 Hz with an AC amplitude of 5 mV.…”

“…It follows the Volmer-Heyrovsky mechanism path for the evolution of H 2 molecules as the rate-determining step. 23,57 Fig. 5c represents the overpotential and Tafel slope comparison of all three as-prepared electrode materials.…”

“…[16][17][18][19] However, the HER performances are still not giving satisfactory results due to the lack of electrical contact between the electrolyte and supporting electrocatalyst, adjustable active sites, and limited charge transport process. [20][21][22][23] To date, the transition metal-based heterostructure phase (metal sulde-selenide, sulde-oxide, selenide-phosphide, and sulde-phosphide) achieved signicant importance for the design of high performance HER electrocatalysts due to the interplay between the two different phases, whereas the intrinsic catalytic activity of the individual phase is different. [24][25][26][27][28][29][30] The performances depend upon the synergistic effect of the two phases.…”

Manganese–cobalt hydroxide nanosheets anchored on a hollow sulfur-doped bimetallic MOF for high-performance supercapacitors and the hydrogen evolution reaction in alkaline media

“…[28][29][30] Manganese and cobalt ions are widely used in the fields of electrochemical energy storage and electrochemical catalysis, benefitting from their multiple oxidation states and higher oxidation potentials. 31,32 Metal-organic frameworks (MOFs) have unique pore structures and metal center ions, attract wide attention and have many applications. 33 The isostructural materials known as MOF-74 [M 2 (dobdc), M = Mn 2+ , Mg 2+ , Ni 2+ , Co 2+ and dobdc = 2,5-dihydroxyterephthalic acid] contain lots of open metal sites, which are beneficial for energy storage and electrochemical catalysis.…”

“…28–30 Manganese and cobalt ions are widely used in the fields of electrochemical energy storage and electrochemical catalysis, benefitting from their multiple oxidation states and higher oxidation potentials. 31,32…”