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Developing low cost and high performance catalyst for oxygen evolution reaction is the key to evolving sustainable energy. We synthesize a well-designed architecture comprising of lead grid wrapping by perpendicularly grown lead oxide flakes. Oxygen evolution activities are largely improved after carving the lead foil into lead grid and further enhanced by a secondary structure of lead oxide flakes, with a negatively-shift of onset potential (~65 mV) and smaller overpotential to deliver a current density of 80 mA cm−2 (~350 mV). The electrode is demonstrated to be highly stable under acidic water at 60 °C for 8 h. We believe the excellence in electrochemistry is attributed to increased active sites, good electrical conductivity and sufficient porosity to facilitate reactant water flow and high gas permeability especially at high current densities. [Display omitted] • Electrode in this work is combined of laser cutting and hydrothermal technology. • OER of lead foils are improved after gridding and covering lead oxide flakes. • The lead oxide/lead grid electrode is highly stable under acidic water at 60 °C. • Positive effects are due to increased active sites, good conductivity and porosity. [ABSTRACT FROM AUTHOR]

In this paper, Ag–ZnO and Ag–MoS 2 –ZnO were successfully synthesized by hydrothermal method. The synthesized samples' physical properties were characterized by FESEM, XRD, TEM, EDS and BET. The catalytic activity of the synthesized samples for the hydrogen evolution reaction was investigated by an electrochemical workstation in 0.1 M KOH. XRD results indicate that 5% Ag-5% MoS 2 –ZnO with good crystallinity and purity is synthesized. According to the SEM results, Ag and ZnO are evenly distributed on the MoS 2 nanosheets in the 5% Ag-5% MoS 2 –ZnO. LSV results show that adding Ag or MoS 2 to ZnO can improve its catalytic activity. 5% Ag - ZnO had the best hydrogen evolution activity, and the overpotential was 568 mV. The catalytic activity of ZnO doped with Ag and MoS 2 is higher than ZnO doped with Ag or MoS 2 alone for hydrogen evolution reaction, this is mainly due to the synergy of heterojunction and Ag. [ABSTRACT FROM AUTHOR]

In the paper, Pd/TiO 2 was successfully prepared by anodic oxidation and electrodeposition. When the time of depositing Pd is 15 min and 5 min, the electrocatalyst is marked as 15 min Pd/TiO 2 and 5 min Pd/TiO 2 respectively. The physical properties of Pd/TiO 2 were characterized by XRD (X-ray diffraction), EDS (energy dispersive spectroscopy), SEM (scanning electron microscope) and XPS (X-ray photoelectron spectroscopy). The catalytic activity of Pd/TiO 2 for hydrogen evolution reaction (HER) in 1 M KOH solution was characterized by the electrochemical workstation. XRD results showed that Pd/TiO 2 was successfully synthesized; the EDS and XPS results confirmed the above results. SEM results show that Pd nanoparticles are uniformly distributed on the surface of TiO 2 nanotube arrays. The electrochemical results show that Pd/TiO 2 has better catalytic activity than TiO 2. Compared with 5 min Pd/TiO 2 and TiO 2 -2h, the overpotential of 15 min Pd/TiO 2 is positively shifted by 98 mV and 588 mV, respectively. The 15 min Pd/TiO 2 still has good catalytic activity after 2000 CV cycles. The catalytic performance of all catalysts in 1 M KOH is better than that in 1 M Na 2 SO 4. Image 1 • Pd/TiO 2 was successfully synthesized by anodic oxidation and electrodeposition. • The overpotential of 15 min Pd/TiO 2 is 149 mV in 1 M KOH. • Pd/TiO 2 showed good stability in 1 M KOH for hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

The key to synthesis highly efficient MoS 2 based electrocatalyst for hydrogen evolution reaction (HER) is to construct a reasonable composite system structure to improve the stability, reduce the aggregation and improve the intrinsic poor conductivity. In this paper, MoS₂ composite of erbium-based metal-organic framework (noted as Er-MOF/MoS 2) were synthesized by hydrothermal method. The morphology and structure of the synthesized samples were characterized by powder X-ray diffraction (XRD), field emission electron microscopy (FESEM), scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS), and the electrocatalytic performances were tested by linear sweep voltammograms (LSV), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), i-t. On the basis of the experiment, Er-MOF/MoS 2 shows improved conductivity and more exposed active sites, exhibiting excellent HER activity in acidic media, with only 234 mV overpotential to achieve 10 mA cm−2, and a Tafel slope of 54.3 mV dec−1. This strategy of porous structure of MoS 2 composite rare earth metal organic framework materials provides a novel and effective solution for preparing high performance MoS 2 based electrocatalyst. • Er-MOF and Er-MOF/MoS 2 were prepared by hydrothermal method. • Er-MOF as supports improved the catalytic activity and more exposed active sites of MoS 2 in acidic media. • Er-MOF/MoS 2 shows excellent long-term durability. [ABSTRACT FROM AUTHOR]

Weak electrical conduction impedes the application of Metal-organic framework (MOF) in electrochemistry. In this work, palladium-based MOF (Pd/MOF) is synthesized via i) simple solvothermal process and ii) direct chemical reduction method. N 2 adsorption-desorption isotherms and thermogravimetric analyzer show that MOF have large specific surface area and good thermal stability. The synthesized materials were tested in acidic condition for hydrogen evolution reaction (HER). Electrochemical test results show that Pd/MOF with tafel slope of 85 mV·dec−1, onset overpotential of 105 mV and ideal stability has better performance than bulk MOF for HER. The enhanced performance can be ascribed to the large porosity and specific surface of MOF, and the synergistic effect between Pd and MOF toward H 2 production. Image 1 • Pd enhanced MOFs has been prepared with a simple two-step method. • Pd/MOFs material has good electrocatalytic activity and stability for HER. • Pd/MOFs are spherical with a radius of 2.2 μm. [ABSTRACT FROM AUTHOR]