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[Display omitted] • The ultrathin RhIr NSs/NF was prepared by a simple and mild one-pot aqueous strategy at room temperature. • The unique sheet-like architectures provided large ECSA and exposed high-density active sites. • The self-supported RhIr NSs/NF had excellent HER activity and stability for the HER over a wide pH range. The development of low-cost and high-efficiency electrocatalysts is very important for electrocatalytic hydrogen evolution reaction (HER) in water splitting system. Herein, ultrathin rhodium-iridium nanosheets were facilely in-situ grown on nickel foam (RhIr NSs/NF) by a one-pot aqueous strategy at room temperature. The sheet-like structures with the film thickness of 78 nm were identified by scanning electron microscopy and transmission electron microscopy. The catalyst showed greatly high HER features in both 1.0 M KOH and 0.5 M H 2 SO 4 with the overpotentials of 15 and 14 mV to achieve 10 mA cm−2, respectively, surpassing most Pt-free catalysts. Also, the RhIr NSs/NF exhibited amazing catalytic stability during the long-term operation. This study offers a facile and rational pathway for design and synthesis of advanced HER electrocatalysts for energy conversion devices. [ABSTRACT FROM AUTHOR]

Developing cost-effectiveness and superior electrocatalysts is crucial to improve the efficiency of oxygen evolution reaction (OER) in water splitting system. Hence, flower-like phosphorus doped Ni 3 S 2 /CoFe 2 O 4 arrays (P-Ni 3 S 2 /CoFe 2 O 4 /NF) were generated on three-dimensional (3D) nickel foam (NF) via the two-step hydrothermal treatment and subsequent phosphorization. Additionally, a series of control experiments were conducted to investigate the formation mechanism. By virtue of the unique 3D configurations and multi-compositions, the as-prepared catalyst exhibited greatly improved OER performance in 1.0 M KOH solution, with the overpotential of only 254 mV at 50 mA cm−2 and low Tafel slope of 54.43 mV dec−1. This study provides a feasible approach for preparing advanced electrocatalyst in energy conversion and storage devices. [ABSTRACT FROM AUTHOR]

Exploring advanced nanocatalysts are of importance for hydrogen evolution reaction (HER) in alkaline electrolyte (e.g. 1.0 M KOH). Herein, porous iridium-palladium-plumbum wire-like nanonetworks (IrPdPb WNNs) were prepared by a facile one-pot aqueous method with octylphenoxypolyethoxyethanol (NP-40) as the structure-director. The resultant IrPdPb WNNs exhibited superior HER performance in the alkaline electrolyte, such as ultra-low overpotential (21 mV) to drive a current density of 10 mA cm−2, small Tafel slope (66 mV dec−1), and high exchange current density (4.87 mA cm−2), surpassing commercial Pt/C. This study provides a simple strategy for synthesis of advanced multi-metallic electrocatalysts in energy storage and conversion. [ABSTRACT FROM AUTHOR]

Hydrogen evolution reaction (HER) is regarded as a feasible strategy for producing high-purity hydrogen from abundant water. It is significant yet challenging for synthesis of Pt-based pH-universal HER electrocatalysts by substantially reducing the Pt loading without any decay in the activity. Herein, bimetallic PtRh alloyed dendritic nanoassemblies (DNAs) were efficiently prepared by a facile one-pot solvothermal strategy in oleylamine (OAm), coupling with the aid of glycine and cetyltrimethylammonium chloride (CTAC). By virtue of the unique branch-like structures and compositions advantages, the PtRh DNAs catalyst showed steeply enhanced HER activity with small overpotentials (i.e. 28 mV in 1.0 M KOH, 23 mV in 1.0 M phosphate buffer solution and 27 mV in 0.5 M H 2 SO 4) at the current density of 10 mA cm−2, surpassing those of commercial Pt/C under such conditions. This work provides a facile and rational strategy to construct advanced Pt-based bimetallic electrocatalyst for energy-correlated applications. Image 1 • PtRh DNAs were synthesized by a one-pot glycine- and CTAC-assisted solvothermal method. • The dendritic nanoassemblies with open structures had highly enlarged specific surface area. • The as-obtained catalyst showed dramatically boosted catalytic performances for HER in a wide pH range. [ABSTRACT FROM AUTHOR]

• The P-Co 2 MnO 4 /NF was synthesized by hydrothermal treatment, oxidation and P-doping. • The unique straw-like nanoneedle arrays provided large ECSA and rich active sites. • P-doping had the greatly improved HER activities. • The P-Co 2 MnO 4 /NF exhibited excellent HER activities in wide pH range of electrolytes. Developing high-performance and cut-price non-noble-metal electrocatalysts for hydrogen evolution reaction (HER) is desirable yet challenging. Herein, straw-like phosphorus-doped Co 2 MnO 4 nanoneedle arrays supported on nickel foam (P-Co 2 MnO 4 /NF) were prepared by successive hydrothermal treatment, oxidation and P doping for high-efficiency HER. Benefiting from the unique needle-like arrays and compositions advantages, P-Co 2 MnO 4 /NF exhibited excellent HER activities with the overpotentials of 33, 43 and 102 mV to afford a current density of 10 mA cm−2 in alkaline, acidic and neutral media, respectively, coupled with the long-term electrochemical stability. This work affords an effective avenue for preparation of cost-effectiveness, high-efficiency and wide-pH HER catalysts for electrochemical energy technologies. [ABSTRACT FROM AUTHOR]