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The electrolytic refining of crude tin is generally carried out in the fluorosilicic acid (H2SiF6) system with the assistance of bone glue and β-naphthol. However, the high saturated vapor pressure and low stability of H2SiF6 present environmental concerns and do not align with sustainable development goals. In this paper, the electrochemical behavior of tin on a glassy carbon (GC) electrode was studied in a relatively green and environmentally friendly methanesulfonic acid (MSA) system. Bone glue, sodium lignosulfonate, and β-naphthol were used as additives to make the deposit morphology smooth and to ensure grain refinement. The electrochemical reduction process of Sn2+ in an MSA system is a quasi-reversible process controlled by diffusion. The apparent activation energy E a = 14.189 kJ/mol for the ion diffusion of Sn2+ was further calculated. The results of chronoamperometry showed that the electrocrystallization of Sn2+ on the GC electrode gradually tended to three-dimensional instantaneous nucleation with the increase in applied potential. The morphology and phase of the deposits were analyzed using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results showed that the deposits were uniform and dense pure tin. This work elucidates the electrochemical behavior of tin in a methanesulfonic acid system. [ABSTRACT FROM AUTHOR]

In this study, a rapid hydrogen-bubble template electrodeposition method was employed to synthesize a dual-functional catalyst (NF/Ni) for alkaline water splitting. Physical characterization revealed that a coarsened NF/Ni with a porous structure was obtained, providing an enlarged surface area. In addition, it revealed that the CV activation is beneficial to the formation of Ni-Ni(OH) 2 coupling interface, which is responsible for reducing of water dislocation energy barrier and providing a balanced H adsorption energy on the Ni site. Consequently, the overpotential of oxygen/hydrogen evolution reaction at 10 mA cm−2 is 290 and 71 mV. In-situ Raman spectroscopies confirm that the generated NiOOH serves as the active center for OER process. When assembled to a two-electrode cell, it showed a cell voltage of 1.62 V@10 mA cm−2, which was 160 mV lower than that of NF‖NF. Furthermore, the university study confirms the formation of hydroxide on the surface of the metal is beneficial to boosting the hydrogen evolution activity. • The NF/Ni was fabricated via hydrogen bubble templated electrodeposition. • The generation coupling interface reduced the free energy of water dislocation. • The generation coupling interface reduced the free energy of Δ GH*. • In-situ Raman spectra reveals that the NiOOH served as the active center. [ABSTRACT FROM AUTHOR]

The development of high‐efficiency, low‐cost, and long‐term stability catalysts for water electrolysis is significant for the sustainable production of hydrogen. The aim of this study is to reduce the overpotential and thus energy consumption. Toward this aim, transition metal sulfide catalyst (marked as S5‐40 doped Ni4Mo) is successfully prepared by a fast one‐step electrodeposition process on a copper foam (CF) substrate. The S20 doped Ni4Mo/CF catalyst displays an exceedingly low overpotential of 140 and −128 mV at 10 mA cm−2 for (oxygen evolution reaction) and (hydrogen evolution reaction), respectively. The S20 doped Ni4Mo/CF can be powered by a commercial AA alkaline battery (1.5 V) in 1.0 m KOH. It shows a lower cell voltage of 1.595 V at 10 mA cm−2 for overall water splitting (OWS). Up to 60 h of stability testing, compared with the S20 doped Ni4Mo/CF catalyst before electrolysis, their performance is improved by 15.5% and 41.1% at 2 and −0.7 V versus reversible hydrogen electrode, respectively. This study offers an avenue to fabricate transition metal sulfide bi‐functional catalysts for OWS and provides deep insights into the relationships among the S‐doping Ni4Mo at the 1.0 m KOH electrolyte physical characterization and electrocatalytic activity. [ABSTRACT FROM AUTHOR]

The principal factor restricting large‐scale hydrogen production via water electrolysis is the development of inexpensive and efficient catalysts that attain high current densities to produces hydrogen at low potentials. In this study, a series of iron‐based phosphide catalysts (denoted as: PX‐doped Fe/NF) were prepared via one‐step electrodeposition from a eutectic solvent to examine their oxygen evolution reaction (OER) or hydrogen evolution reaction (HER) performance. Notably, P30‐doped Fe/NF forms a porous interconnected nanosheet structure, providing a large active surface areas, abundant active sites and low charge transfer resistance. P30‐doped Fe/NF attained the lowest OER (284.15 mV) and HER (158.17 mV) overpotentials at 10 mA cm−2 in 1.0 M KOH of all the tested catalysts. When used in overall water splitting, the catalyst displayed outstanding adaptability to a range of potentials and current densities. This study provides a facile route for the synthesis of bifunctional transition‐metal phosphide catalysts for the electrolysis of water. [ABSTRACT FROM AUTHOR]