Electrochemical deposited amorphous FeNi hydroxide electrode for oxygen evolution reaction

The electrodeposition approach is significant in electrode fabrication for practical application.Herein,the electrodeposited amorphous NiFe hydroxide species for oxygen evolution reaction (OER) in water splitting reaction is demonstrated by revealing the synergistic effect influenced by the support electrode of Fe and Ni foil and the contents of Fe and Ni in the electrolyte.All the electrodeposited samples have an amorphous structure and similar profiles of binding energy and chemical states for Fe and Ni as characterized by the spectroscopic techniques.While the support effect and Fe/Ni synergistic effect are indeed observed for the varied catalytic performances observed for the different electrodes;the Ni foil supported catalyst exhibits much higher performance than that of the Fe foil supported catalyst,and the different redox potentials of Ni species in the different Fe/Ni electrode resulting from the Fe–Ni synergism are observed in the cyclic voltammetry curve analysis.The surface roughness and the electrochemical surface area are also influenced by the support effect and the Fe/Ni ratio in the plating electrolyte.The optimal electrode shows a very low overpotential of~200 mV to reach 10 mA cm^(-2),and very high catalytic stability by the consecutive cyclic voltammetry measurements and 20 h stability test.Though it has the largest electrochemical surface area,the highest catalytic efficiency for these active sites is also indicated by the specific activity and turnover frequency polarization curves.The current work shows the effective experience for the electrodeposited Fe/Ni based catalysts in large-scale fabrication,which can be more practical for hydrogen generation in the alkaline water electrolysis.

Amorphous FeCoNi-S as efficient bifunctional electrocatalysts for overall water splitting reaction

Developing bifunctional electrocatalysts for overall water splitting reaction is still highly desired but with large challenges. Herein, an amorphous Fe Co Ni-S electrocatalyst was developed using thioacetamide for the sulfuration of Fe Co Ni hydroxide during the hydrothermal process. The obtained catalyst exhibited an amorphous structure with hybrid bonds of metal-S bond and metal-O bonds in the catalyst system. The optimized catalyst showed a largely improved bifunctional catalytic ability to drive water splitting reaction in the alkaline electrolyte compared to the Fe Co Ni hydroxide. It required an overpotential of 280 m V and 80 m V(No-IR correction) to offer 10 m A/cm^(2)for water oxidation and reduction respectively;a low cell voltage of 1.55 V was required to reach 10 m A/cm^(2)for the water electrolysis with good stability for12 h. Moreover, this catalyst system showed high catalytic stability, catalytic kinetics, and Faraday efficiency for water splitting reactions. Considering the very low intrinsic activity of Fe Co Ni hydroxide, the efficient bifunctional catalytic ability should result from the newly formed hybrid active sites of metallic metal-S species and the high valence state of metal oxide species. This work is effective in the bifunctional catalytic ability boosting for the transition metal materials by facile sulfuration in the hydrothermal approach.

Charge Transport through Peptides in Single-Molecule Electrical Measurements

Charge transport across the peptide chains is one of the vital processes in the biological systems,so understanding their charge transport properties is an indispensable prerequisite to explain the complex biochemical phenomenon.Here,we review the charge transport mechanism,the influence of the special groups and the experimental conditions on the charge transport through the peptide backbone by employing the single-molecule electrical measurements.Besides,we further review the recent progresses in charge transport properties of supramolecular interaction among the adjacent peptide chains.Finally,we discuss some experimental and theoretical contradictions existing in the charge transport through peptides and provide new inspiration for the future development of the bioelectronics at the single-molecule scale.