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AuCo alloys were prepared by magnetron sputtering for the first time without considering the insolubility on the phase diagram. The electronic effect between Au and Co can change the oxygen adsorption energy and the ORR activity. The ORR activity of the Au46Co54 alloy electrode not only exceeded that of Au, but also exceeded that of Pt in basic solution. [ABSTRACT FROM AUTHOR]

Nano-network Ru with definite lattice defects on amorphous Co nanosheets is obtained for the first time. Amorphous Co support can promote the surface Ru to obtain special morphology and modified electronic structure, thus improving HER activity in alkaline solution. A current density of 10 mA cm−2 can be obtained only with an overpotential of 33.5 mV. [ABSTRACT FROM AUTHOR]

An obvious H-UPD for a nano AuTiO2−x composite has been found for the first time in terms of the electrochemical characteristics of the Au composite. The electronic effect between Au and TiO2 and the oxygen vacancy defect would change the adsorption energy of H and HER activity. The HER activity of the AuTiO2−x electrode is 6.44 times that of the Au electrode. [ABSTRACT FROM AUTHOR]

The development of highly active and long-term stable electrocatalysts for the hydrogen evolution reaction (HER) is very important. Because of the hysteresis phenomenon, IrO2 is rarely used as a cathode material for the HER. Herein, an IrO2–TiO2 composite oxide was prepared using the thermal decomposition method. The physical and electrochemical characterization of the materials was achieved by scanning electron microscopy (SEM), X-ray fluorescence (XRF), X-ray diffraction (XRD), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). In the process of the HER, the current of IrO2 is only 1.91 mA cm−2@−0.2 V in the first segment scan. However, at the 51, 101 and 151 segment scan, the HER current increases to 6.85, 15.7 and 18.2 mA cm−2@−0.2 V, respectively. During the activation process of IrO2, the HER current has increased ten times. Compared with the HER activity of IrO2, there is almost no hysteresis for the IrO2–TiO2 electrode. In the first segment scan, the HER current has already reached 27.9 mA cm−2@−0.2 V and further increased to 31.1, 33.1 and 35.0 mA cm−2 at the 51, 101 and 151 segment scan. The difference between them is not significant, which means that the IrO2–TiO2 electrode does not need activation. The IrO2–TiO2 electrode has exhibited a higher HER activity than the IrO2 electrode, which may be attributed to the electronic structure modification and the increase of the electrochemical area. [ABSTRACT FROM AUTHOR]

The potential ofOsmanthus fragranspowder as a natural biosorbent was investigated for the removal of methylene blue (MB) from aqueous solution. The effects of various experimental conditions including contact time, adsorbent dose, initial MB concentration, solution pH, salt ionic strength, and temperature on the adsorption properties ofO. fragranspowder were discussed. The adsorption kinetic data were modeled using pseudo-first-order, pseudo-second-order, and intraparticle diffusion kinetics equations, indicating that the pseudo-second-order and intraparticle diffusion models could better describe the adsorption kinetics. Furthermore, adsorption equilibrium data were analyzed by Langmuir and Freundlich models, suggesting the Langmuir model presented a better correlation with the experimental data. The maximum adsorption capacities (qm) ofO. fragranspowder for MB obtained from the Langmuir model were 155.52, 165.02, and 172.71 mg g−1at different temperatures of 288.15, 298.15, and 308.15 K, respectively. Thermodynamic parameters such as standard free energy changes (ΔG°), standard enthalpy changes (ΔH°), and standard entropy changes (ΔS°) were also calculated. The results showed that the adsorption process was spontaneous and endothermic in nature. In addition, the possible adsorption mechanism ofO. fragranspowder as adsorbent was proposed. The present study implies thatO. fragranspowder were a promising candidate as novel biosorbents for the removal of MB from aqueous solution. [ABSTRACT FROM AUTHOR]

The food hygiene problems caused by bacterial biofilms in food processing equipment are directly related to human life safety and health. Therefore, it is of great strategic significance to study new food sterilization technology. An acidic electrolyzed water (AEW) disinfectant is an electrochemical sterilization technology which has the characteristics of wide adaptability, high efficiency, and environmental friendliness. However, since the sterilization efficiency of AEW for biofilms is not ideal, it is necessary to increase the available chlorine content (ACC) in AEW. A feasible method to increase the ACC is by increasing the chlorine evolution reaction (CER) selectivity of the electrode for AEW preparation. In this paper, the RuO 2 @TiO 2 electrode was prepared by thermal decomposition combined with high-vacuum magnetron sputtering. Compared with the oxygen evolution reaction (OER) activity of an ordinary RuO 2 electrode, the OER activity of the RuO 2 @TiO 2 electrode is significantly reduced. However, the CER activity of the RuO 2 @TiO 2 electrode is close to the OER activity of RuO 2 . The CER mechanism of the RuO 2 @TiO 2 electrode is the second electron transfer, and the OER mechanism is the formation and transformation of OH ads . The potential difference between the CER and OER of the RuO 2 @TiO 2 electrode is 174 mV, which is 65 mV higher than that of the RuO 2 electrode, so the selectivity of the CER of the RuO 2 @TiO 2 electrode is remarkably improved. During the preparation of AEW, the ACC obtained with the RuO 2 @TiO 2 electrode is 1.7 times that obtained with the RuO 2 electrode. In the sterilization experiments on Escherichia coli and Bacillus subtilis biofilms, the logarithmic killing values of AEW prepared the by RuO 2 @TiO 2 electrode are higher than those of AEW prepared by the RuO 2 electrode., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

A nano Ir x Mn (1- x ) O y hybrid electrode with a L1 2 -IrMn 3 phase was used as a bifunctional catalyst with ultra-low iridium loading for overall water electrolysis in an acid solution for the first time. The HER activity of the Ir x Mn (1- x ) O y hybrid electrode not only exceeded that of IrO 2 , but also exceeded that of Pt/C. The OER activity of the Ir x Mn (1- x ) O y hybrid electrode also exceeded that of IrO 2 .

Electrochemical water splitting technology is considered to be the most reliable method for converting renewable energy such as wind and solar energy into hydrogen. Here, a nanostructured RuO 2 /Co 3 O 4 -RuCo-EO electrode is designed via magnetron sputtering combined with electrochemical oxidation for the oxygen evolution reaction (OER) in an alkaline medium. The optimized RuO 2 /Co 3 O 4 -RuCo-EO electrode with a Ru loading of 0.064 mg cm -2 exhibits excellent electrocatalytic performance with a low overpotential of 220 mV at the current density of 10 mA cm -2 and a low Tafel slope of 59.9 mV dec -1 for the OER. Compared with RuO 2 prepared by thermal decomposition, its overpotential is reduced by 82 mV. Meanwhile, compared with RuO 2 prepared by magnetron sputtering, the overpotential is also reduced by 74 mV. Furthermore, compared with the RuO 2 /Ru with core-shell structure ( η = 244 mV), the overpotential is still decreased by 24 mV. Therefore, the RuO 2 /Co 3 O 4 -RuCo-EO electrode has excellent OER activity. There are two reasons for the improvement of the OER activity. On the one hand, the core-shell structure is conducive to electron transport, and on the other hand, the addition of Co adjusts the electronic structure of Ru., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

An obvious H-UPD for a nano AuTiO2-x composite has been found for the first time in terms of the electrochemical characteristics of the Au composite. The electronic effect between Au and TiO2 and the oxygen vacancy defect would change the adsorption energy of H and HER activity. The HER activity of the AuTiO2-x electrode is 6.44 times that of the Au electrode.