Electrochemical nitrogen-to-ammonia fixation is emerging as a sustainable strategy to tackle the hydrogen- and energy-intensive operations by Haber-Bosch process for ammonia production. However, current electrochemical nitrogen reduction reaction (NRR) progress is impeded by overwhelming competition from the hydrogen evolution reaction (HER) across all traditional NRR catalysts and the requirem...

The hydrogen evolution reaction (HER) on an electrodeposited a-MoS2 electrode was investigated by a surface-selective electrochemical titration technique by application of surface interrogation scanning electrochemical microscopy. In a mildly acidic (pH 4.6) environment, the saturated surface hydride coverage of MoS2 was determined to be 31%, much higher than that expected for a crystalline nan...

Hydrogen evolution production via electrolysis of water in alkaline solution is a promising mean industrial hydrogen production. However, inefficiency and high cost restrict its industrialization development. Based on extensive studies experimental theoretical investigations, two-dimensional (2D) materials are substitute noble metals for reaction (HER) with low high-efficiency. Herein, recent p...

Microkinetic analyses of aqueous electrochemistry involving gaseous H2 or O2, i.e., hydrogen evolution reaction (HER), hydrogen oxidation reaction (HOR), oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), are revisited. The Tafel slopes used to evaluate the rate determining steps generally assume extreme coverage of the adsorbed species (θ≈0 or ≈1), although, in practice, the ...

A new approach to the simultaneous measurement of hydrogen evolution reaction (HER) and elemental dissolution rates is presented applied galvanized steel coatings with HCl solution. Dissolution profiles revealed several kinetic regimes including intact coating, nanometric Fe2Al5 intermetallic layer, corrosion substrate. The HER Zn were in excellent agreement, quantities interfacial Fe Al consis...

We report a Ni-Cr/C electrocatalyst with unprecedented mass-activity for the hydrogen evolution reaction (HER) in alkaline electrolyte. The HER kinetics of numerous binary and ternary Ni-alloys and composite Ni/metal-oxide/C samples were evaluated in aqueous 0.1 M KOH electrolyte. The highest HER mass-activity was observed for Ni-Cr materials which exhibit metallic Ni as well as NiO x and Cr2O3...

In this present study, a series of cobalt porphyrin-based conjugated mesoporous polymers (CoP-nph-CMP, n = 2, 3, 4) were fabricated as catalyst precursors to generate bifunctional catalysts via pyrolysis (CoP-nph-CMP-800, n = 2, 3, 4) for both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER). Among these catalysts, CoP-2ph-CMP-800 exhibited the best catalytic activi...

Impedance spectra of the hydrogen evolution reaction, HER, at low cathodic overpotentials were analyzed on the basis of the theoretical admittance/frequency function, initially derived for the Volmer-Heyrovsky-Tafel reaction mechanism involving the hydrogen insertion (absorption + diffusion) step. General principles of the impedance spectroscopy for HER are discussed using schematically constru...

Developing low-cost and highly active electrocatalysts to replace Pt group metals is very critical the hydrogen evolution reaction (HER). Transition-metal carbides (TMCs) have drawn broad attention as potential HER catalysts in recent years due platinum-like electron structure. This review highlights strides on synthesis routes optimization strategies of TMC electrocatalysts, discusses future p...

Hydrogen is an efficient, clean, and economical energy source, owing to its huge density. Electrochemical water splitting a potential candidate for inexpensive eco-friendly hydrogen production. Recently, the development of 2D transition metal chalcogenides (TMDs) nanomaterials with variety physicochemical properties has shown their as eminent non-noble metal-based nanoscale electrocatalysts evo...