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Despite the expectation on transition‐metal phosphides as precious‐metal‐free electrocatalysts, the reported performance of these materials still necessitates further improvement. Ingenious regulations of both geometric and electronic structure have been proposed as an effective approach to boost their electrocatalytic properties. In this regard, the self‐supported V doped CoP nanowires on nickel foam are prepared to accommodate both optimized electronic structure and desired nanostructure, which enable large surface area, abundant active sites exposure, low charge transfer resistance, as well as favorable H* adsorption. As for the alkaline hydrogen evolution, it only requires a lower potential of 79 mV and 125 mV to drive 10 mA ⋅ cm−2 and 100 mA ⋅ cm−2 current with a Tafel slope of 47.41 mV ⋅ dec−1, which prevails over commercial Pt/C catalysts. The catalyst also exhibits excellent durability to retain activity unchanged for more than 16 h. Such a simple and convenient strategy by electronic tuning and structure design provides a new avenue toward the exploration of efficient electrocatalysts. [ABSTRACT FROM AUTHOR]

Development of efficient non-precious and abundant electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is one of the key tasks in renewable energy technologies. Transition-metal selenides have been widely studied as promising candidates. Herein, a layer-structured CoSe2 was used as a precursor, followed by simple one-step dopamine coating. The as-prepared Co0.85Se@NC showed outstanding performance in both ORR and OER catalysis. The onset potential and half-wave potential of the ORR in 0.1 M KOH solution can reach 0.96 V and 0.85 V, respectively. The OER overpotential corresponding to 10 mA cm−2 in 1.0 M KOH solution is only 350 mV, which is much smaller than that of RuO2 (390 mV). Importantly, the catalyst showed good stability, demonstrating that the layered Co0.85Se@NC has great potential for advanced bifunctional electrocatalysis. [ABSTRACT FROM AUTHOR]

The crystal phase plays an important role in controlling the properties of a nanomaterial; however, it is a great challenge to obtain a nanomaterial with high purity of the metastable phase. For instance, the large‐scale synthesis of the metallic phase MoS2 (1T‐MoS2) is important for enhancing electrocatalytic reaction, but it can only be obtained under harsh conditions. Herein, a spatially confined template method is proposed to synthesize high phase‐purity MoS2 with a 1T content of 83 %. Moreover, both the confined space and the structure of template will affect the purity of 1T‐MoS2; in this case, this approach was extended to other similar spatially confined templates to obtain the high‐purity material. The obtained ultrathin nanosheets exhibit good electrocatalytic activity and excellent stability in the hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

Due to energy crisis and environmental pollution, it is urgent to develop efficient and cheap catalysts for hydrogen production from water electrolysis. As a cheaper platinum group metal, Ru, a cheaper platinum group metal, is a highly competitive candidate to Pt because of the similar bond energy of M-H. Herein, TiO 2 @nitrogen-doped carbon composite supported superfine Ru nanoparticles was synthesized by high temperature shock in a Joule furnace using Ti-MOF support (Ru/TiO 2 @NC-J). In the extremely rapid process, MOF was quickly converted into highly conductive nitrogen-doped carbon with tiny TiO 2 dispersed in it, and superfine Ru nanoparticles were generated simultaneously in less than 0.5 s. The obtained Ru/TiO 2 @NC-J displays wonderful HER performance in the wide pH range. In 1.0 M KOH solution, the overpotential was as low as 11 mV at 10 mA cm−2 and a Tafel slope was 39.2 mV dec−1, which far exceeded the activity of Pt/C and conventional calcined samples as well as most of the recently reported catalysts. The as-developed electrocatalysts also showed excellent stability to accommodate large working current for long term test without obvious activity loss in universal pH range. Experimental investigations suggest that the strong metal-support interaction dominantly facilitate the activity of electrocatalytic hydrogen evolution reaction (HER), and stability of Ru/TiO 2 @NC-J. This strategy provides a new and super-fast methodology to prepare low-budget and high-performance HER catalysts for practical applications. [Display omitted] • Highly durable and active Ru/TiO 2 @NC-J catalyst was synthesized by using the novel high temperature shock strategy. • The pH-universal catalyst simultaneously exhibits drastically reduced overpotential and Tafel slope. • Ru/TiO 2 @NC-J achieved high stability in universal pH range. • The excellent catalytic HER performance originate from the strong metal-support interaction. [ABSTRACT FROM AUTHOR]

Developing cost effective, active and durable alternatives to platinum electrocatalysts is the major challenge for sustainable hydrogen production. Rational design and controlled synthesis of hybrid structures with strong metal-support interaction may offer a feasible strategy to achieve efficient and stable hydrogen evolution reaction (HER). Herein, a low cost and high-performance ultrafine Ru nanoparticles anchored tungsten carbide (Ru/WC) HER electrocatalyst is successfully prepared by high-temperature shock (HTS) technology, which can be accomplished in less than 0.5 s. In a strong alkaline medium, the as-prepared Ru/WC exhibits a low overpotential of 4 mV and 72 mV at the current densities of 10 mA cm−2 and 100 mA cm−2, respectively. Low Tafel slope of 44 mV dec−1, high turnover frequency (TOF) of 2.55 s−1 at an overpotential of 100 mV, long-term electrochemical stability up to 150 h, and ampere-level current density can be achieved. Furthermore, Ru/WC also shows exceptional activity and stability under acidic conditions. Notably, Ru/WC can accommodate HER current density as high as 2000 mA cm−2 at a small overpotential of 365 mV, which holds great promises for industrial large-scale production. This work provides a simple, rapid, and solvent-free strategy for synthesizing high efficiency HER electrocatalyst with ampere-level current density. [Display omitted] • Ultrafine Ru nanoparticles anchored tungsten carbide (Ru/WC) was prepared by high-temperature shock technology. • Ru/WC displays quite small HER overpotentials and large TOF value in alkaline and acid solution. • Ru/WC can reach ampere-level current density of HER at low overpotentials in alkaline and acid solution. • The metal-support interaction between ultrafine Ru and WC contributes to the excellent HER performance. [ABSTRACT FROM AUTHOR]

To improve the surface activity of molybdenum (Mo), a method combining anodizing and deoxidizing annealing in a H 2 atmosphere has been proposed to prepare nanocone-structured active Mo foils (NCSAMFs) in this paper. The morphology, composition and catalytic properties of the as-prepared NCSAMF were characterized by field-emission scanning electron microscopy (FESEM), energy dispersive spectrometry (EDS) and electrochemical measurements. Nanoconical structures were generated under a voltage of 20 V for 15 min in the optimized electrolyte, and all the oxygen atoms in the nanoconical structure layer were removed under deoxidation at 650 °C for 3 h in a H 2 atmosphere while retaining the nanoconical structure and activity. Compared with the Mo foils treated under different conditions, the NCSAMFs exhibit superior hydrogen evolution reaction (HER) activity with a low onset overpotential of 123 mV and a Tafel slope of 96 mV dec−1, indicating that the NCSAMFs possess high activity and outstanding long-term stability in acidic media. Therefore, the NCSAMFs prepared in this paper are promising transition metal HER electrocatalysts and serve as active matrix materials for Mo-based materials. In addition, the surface energies of the NCSAMF and the Mo foils without nanotreatment were calculated at the atomic and mesoscopic scales, respectively, to provide more insights into the origin of the studied process, and the calculation results demonstrate that the high activity of NCSAMFs is mainly derived from the increase in Mo crystal surface area with high surface energy caused by the nanotreatment and the corresponding increase in the amount of active sites. Image 1 • Molybdenum foils were anodized in NH 4 F electrolytes to prepare a nanocones on the surface. • A deoxiding annealing process is carried out to obtain nanocone-structured active Mo foils (NCSAMFs). • The electrochemical catalytic activity is tested. • The surface energies are calculated at atomic and mesoscopic scales, respectively. [ABSTRACT FROM AUTHOR]