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Regulating the metal‐support interaction of the anchored metal nanoclusters is recognized as valid approach to optimize the electrocatalytic performance through tuning the interfacial electronic structure. However, developing novel support and understanding the interfacial electron accumulation on modulating the reaction kinetics are still elusive. Herein, highly‐dispersed Ruthenium (Ru) nanoclusters anchored onto phosphorous doped molybdenum boride (Ru/P‐MoB) is developed through ultrafast microwave‐plasma (60 s) approach. The synthesized Ru/P‐MoB impressively promote the hydrogen evolution with low overpotentials of 34, 45, and 40 mV to drive 10 mA cm−2 in alkaline freshwater, alkaline seawater and acid media. Specially, it presents superior turnover frequency and mass/specific activity relative to Pt/C, Ru/C, and Ru/MoB. Moreover, the anion exchange membrane (AEM) electrolyzer cell based on Ru/P‐MoB can achieve 500 and 1000 mA cm−2 with small voltages of 1.71 and 1.78 V with good durability. Experimental and density functional theoretical (DFT) analysis reveal that the strong metal‐support interactions (Ru─Mo and Ru─P bonds) with generated interfacial electron‐enriched Ru, and then favoring the water‐molecule adsorption/dissociation and optimal H intermediate adsorption free energy. This work provides novel designing avenue to exploit electrocatalysts with outstanding catalytic performance under high current density at practical high‐temperature. [ABSTRACT FROM AUTHOR]

Design and construction of efficient and robust electrocatalysts for the hydrogen evolution reaction (HER) are of great importance for renewable energy technologies, but challenge remains for the large-scale commercial application. The good stability and large electrochemical active area of nanomaterials have been widely studied in the field of energy storage and conversion. Regulating the d band electronic structure has been considered as a powerful approach to boost the HER activity. Herein, an efficient electrocatalyst comprising Ni nanoparticles anchored on the N-doped carbon matrix derived from a fullerene/nickel tetraphenylporphyrin (C60/NiTPP) nanoflower assembly was fabricated successfully. The as-synthesized Ni-(TPP)/NC exhibited promising HER activity under alkaline condition. To deliver a current density of 10 mA cm–2, it required an overpotential of 114 mV along with a nearly 100% Faradaic efficiency. Both experimental and density functional theory calculation results revealed that the pyrrolic N could modulate the 3d band center of Ni sites in Ni-(TPP)/NC, which facilitate the adsorption of water molecules and desorption of hydrogen intermediates, leading to the reduced kinetic energy barrier and enhanced electrocatalytic HER activity. This work would provide useful guidance for designing and developing efficient electrocatalysts for hydrogen production. [ABSTRACT FROM AUTHOR]

Oxygen vacancies‐enriched black TiO2 is one promising support for enhancing hydrogen evolution reaction (HER). Herein, oxygen vacancies enriched black TiO2 supported sub‐nanometer Pt clusters (Pt/TiO2‐OV) with metal support interactions is designed through solvent‐free microwave and following low‐temperature electroless approach for the first time. High‐temperature and strong reductants are not required and then can avoid the aggregation of decorated Pt species. Experimental and theoretical calculation verify that the created oxygen vacancies and Pt clusters exhibit synergistic effects for optimizing the reaction kinetics. Based on it, Pt/TiO2‐OV presents remarkable electrocatalytic performance with 18 mV to achieve 10 mA cm−2 coupled with small Tafel slope of 12 mV dec−1. This work provides quick synthetic strategy for preparing black titanium dioxide based nanomaterials. [ABSTRACT FROM AUTHOR]

Seawater electrolysis is a potential way to realize the large-scale hydrogen production without relying on freshwater resources, but limited by the chlorine evolution reaction (ClER) on the anode and high potential for seawater electrolysis. In this work, MOF-derived Ru, Fe dual-doped Ni 2 P nanosheets (RuFe-Ni 2 P@NF) is constructed to serve as bifunctional catalyst for chlorine-free hydrogen production by hybrid hydrogen evolution reaction (HER) coupled with hydrazine oxidation reaction (HzOR) in seawater. As an ideal bifunctional electrocatalyst for overall hydrazine splitting (OHzS) in seawater, RuFe-Ni 2 P@NF catalyst only needs 0.69 V to achieve 1000 mA cm−2. Moreover, the energy-saving H 2 production is realized by utilizing OHzS unit, which can save 4.70 W · h of electricity compared with the N 2 H 4 -free unit for producing 1.0 L of H 2. Moreover, the direct hydrazine fuel cell (DHzFC) is assembled to drive OHzS to realize the self-powered H 2 production. The industrial hydrazine sewage can serve as feed for the above eletrolysis system, which has been degraded to ∼ 8 ppb rapidly. DFT calculations demonstrate that the Ru and Fe dual-doping can not only realize the thermoneutral ΔG H* for HER but also decrease the free energy of dehydrogenation of *N 2 H 3 to *N 2 H 2 for HzOR, realizing the intrinsically enhanced dehydrogenation kinetics. [Display omitted] • Ru, Fe dual-doped Ni 2 P nanosheets (RuFe-Ni 2 P@NF) with the typical nanosheet-like structure is in-situ grown on nickel foam. • RuFe-Ni 2 P@NF shows excellent HER, HzOR and overall hydrazine splitting (OHzS) performance in alkaline seawater. • DFT demonstrate that dual-doping can realize the thermoneutral ΔG H* for HER and accelerate dehydrogenation for HzOR. • The direct hydrazine fuel cell (DHzFC) is assembled to drive OHzS to realize the self-powered H 2 production. • The industrial hydrazine sewage can serve as feed for the eletrolysis system, which has been degraded to ∼8 ppb rapidly. [ABSTRACT FROM AUTHOR]

[Display omitted] • The flower-like Co@CoP 2 /CF was synthesized by hydrothermal and calcination method. • The flower-like morphology of electrocatalyst depends on Phytic acid concentration. • The electrocatalyst shows excellent HER and OER performance and good stability. • The excellent activity is due to unique morphology and interfacial charge regulation. • The electrocatalyst only needs cell voltage of 1.54 V to drive water splitting at 10 mA cm−2. Transition metal phosphide (TMP) is one of the most potential electrocatalysts for hydrogen evolution reaction (HER), whereas it is still immensely challenging to construct TMP-based catalyst that performs the excellent catalytic activity for both HER and oxygen evolution reaction (OER) through the proper regulation strategies. Herein, the morphology and interfacial charge regulation strategies were proposed to construct 3D flower-like Co@CoP2 heterostructure electrocatalyst grown in situ on copper foam (CF) for HER and OER. The influence of the phytic acid concentration on the product morphology and composition was systematic investigation. The flower-like Co@CoP 2 Mott-Scottky heterostructure grown on CF (Co@CoP 2 /CF(1:1)) prepared under the optimal conditions shows the eminent electrocatalytic activity of HER with an overpotential of 55 mV and OER with an overpotential of 210 mV at a current density of 10 mA cm−2 in alkaline solution. Remarkably, Co@CoP 2 /CF(1:1)//Co@CoP 2 /CF(1:1) electrolyzer displays a prominent overall water splitting performance with a voltage of 1.54 V at the current density of 10 mA cm−2, and maintained excellent stability over a period of 100 h operating in 1 M KOH, which is superior to the almost all the reported non-noble-metal-based electrocatalysts. Various ex situ characterizations and density functional theory (DFT) calculations manifested that the superior electrocatalytic performance of Co@CoP 2 /CF (1:1) was attributed to high P content, more important, the unique flower-like morphology and the efficient regulation of interfacial charge drived by the Mott-Scottky effect. This work offers a universal regulation strategy for improve electrocatalytic activity, and opens up a new way for the exploitation of the efficient bifunctional electrocatalysts. [ABSTRACT FROM AUTHOR]

Designing efficient and robust pH-universal electrocatalysts for hydrogen evolution reaction (HER) is the key to boost the development of eco-friendly hydrogen energy. Herein, metallic Mo, Ru coupled with graphitic carbon dots (GQDs) activate inertness 1D copper-based nanowires (GQDs@ Ru, Mo-Cu 2 O/CF) by surface chemical oxidation, solvothermal and low temperature calcination. The metals of Mo, Ru favor the water-dissociation and optimize the hydrogen adsorption/desorption. In addition, GQDs owns edge effect and good conductivity, and then benefiting electron transport and active sites exposure. Therefore, the synthesized GQDs@ Ru, Mo-Cu 2 O/CF requires only 30, 39, 17 and 55 mV in alkaline, acidic, alkaline seawater and neutral to achieve 10 mA cm−2. Moreover, the assembled electrolyzer requires 1.58 V to reach 10 mA cm−2 in alkaline seawater, and maintained well at 200 mA cm−2 for 100 h. This research opens a new avenue for designing efficient catalysts on energy-relation applications through introducing both metal and non-metal. [Display omitted] • Introducing Mo, Ru and GQDs to activate inert Cu-based nanowires to achieve efficient HER. • 1D nanowires is modified by metal particles and GQDs through a simple and valid approach. • The assembled electrolyzer has excellent stability at 200 mA cm−2 for 100 h in alkaline seawater. [ABSTRACT FROM AUTHOR]

The preparation of stable, efficient and pH-universal hydrogen evolution reaction (HER) electrocatalysts is urgent and significant for large-scale hydrogen production. Herein, a simple and efficient method was developed to fabricate Ru-doped MoO 2 /Mo 2 C onto N-doped carbon nanoparticles (Ru-MoO 2 /Mo 2 C/NC). The formed smaller nanoparticles by Ru doping can provide abundant accessible active sites and interfaces. Moreover, the synergistic effects of Ru and Mo-based compounds also played a key role in promoting the catalytic kinetics. The as-prepared Ru-MoO 2 /Mo 2 C/NC exhibited low overpotentials of 38, 61, 67 and 75 mV in alkaline, neutral, acidic electrolyte solutions and alkaline seawater at 10 mA cm−2, respectively. This work proposes a valid method for the design of efficient electrocatalysts through precise component regulation. • One-step pyrolysis approach is used to design Ru doped MoO 2 /Mo 2 C onto N-doped carbon. • The introduced Ru can regulate the nanoparticle to expose abundant active sites. • The developed Ru-MoO 2 /Mo 2 C/NC presents all-pH HER performance and long-term stability. [ABSTRACT FROM AUTHOR]

• NiCo-LDH decorated NiCoS nanorods with hierarchical structure has been prepared. • The moderate amount of NiCo-LDH by electrodeposition could enhance the activity. • The synergistic effect of the composite contribute to the enhanced performance. As the key step in the overall water splitting system, hydrogen evolution reaction (HER) has become one of the main methods of hydrogen production in industrial applications. Here, through the strong coupling between NiCo-LDH nanosheets and NiCoS nanorods, the three-dimensional heterogeneous structure formed by the composite can provide a large catalytic specific surface area. The modification of LDH lamellar will provide abundant edge active sites and enhance its structural stability. The synergistic effect of NiCo-LDH and NiCoS can optimize the electronic structure and promote mass transfer and water cracking. Benefiting from the above points, the NiCoS@NiCo-LDH/NF obtained showed the significant boost in HER process. It only required 99 mV to reach current density of 10 mA·cm−2 and maintained excellent durability for 24 h for HER, which proved NiCoS@NiCo-LDH/NF was a cost-free, high-efficient and outstandingly stable HER catalyst in basic solution. [ABSTRACT FROM AUTHOR]

[Display omitted] • Corrosive engineering and low-temperature phosphorization approach is developed. • Amorphous morphology and superhydrophilic surface provide abundant active sites. • Excellent electrocatalytic performances are achieved for HER and OER. • Electrocatalyst exhibits remarkable performance and stability for water-splitting. Developing highly efficient and low-cost electrocatalysts toward hydrogen/oxygen evolution reactions (HER/OER) under the large current act as a pivotal role in their large-scale practical applications. Herein, corrosive engineering and low-temperature phosphorization approach is applied to prepare amorphous Mo-doped NiFeP onto nickel–iron foam (Mo-NiFeP/NIF). The amorphous morphology, the porous NIF and the superhydrophilic surface provide abundant active sites during the electrocatalytic process. Moreover, the high-valence Mo also favors the charge transfer to boost the reaction kinetics. Then, the prepared Mo-NiFeP/NIF achieves 10 mA cm−2 for OER with low overpotentials of 207 mV and 257 mV in 1 M KOH and 1 M KOH + seawater electrolytes, respectively, coupled with remarkable stability under large current density. Moreover, the prepared Mo-NiFeP/NIF also presents excellent electrocatalytic performance for HER with 58 mV to obtain 10 mA cm−2 in KOH. For overall water-splitting, a low cell voltage (1.55 V) is required to achieve 10 mA cm−2 in 1 M KOH and it can be powered by sustainable energy sources, including wind, solar and thermal energies. [ABSTRACT FROM AUTHOR]

Ru/h-B-Fe-P was synthesised by low temperature phosphorization, acid etching and microwave loading Ru. The designed catalyst has good activity and stability over a wide pH range. [Display omitted] • Ru/h-B-Fe-P is developed by phosphorization, acid etching and microwave treatment. • Ru/h-B-Fe-P was etched by HCl to form hollow structure with more active sites. • The coupling effect of Ru and FeP enhances the reaction kinetics of HER. • Ru/h-B-Fe-P presents excellent all-pH HER performance and long-term stability. • Two-electrode electrolyzer can be powered by sustainable energies, including solar. Designing highly efficient catalysts act as a key role for the green and sustainable hydrogen production through water electrolysis. In this work, hollow structured B-doped FeP nanospheres supported Ru (Ru/h-B-Fe-P) is developed by low temperature phosphorization, acid etching and following microwave treatment approach. The hollow structure, abundant defects and electronic interactions between Ru and FeP can favour the mass transport and boosting the reaction kinetics toward all-pH hydrogen evolution reaction (HER). Then, Ru/h-B-Fe-P achieves excellent catalytic activities in acidic, neutral, alkaline, and alkaline seawater electrolytes with only 56 mV, 79 mV, 88 mV and 99 mV to drive 10 mA cm−2 with remarkable stability. This work indicates that decorated noble metals onto specific nanostructured matrix is a promising approach to enhance the catalytic activities. [ABSTRACT FROM AUTHOR]

Through a LDH coating and step-by-step phosphating process, the triple-shell CoP@CoP@(Co/Ni) 2 P hollow structure with the rich defect has been successfully constructed. The CoP@CoP@(Co/Ni) 2 P presents excellent HER activity over a wide pH range, with the overpotentials of 147 mV, 139 mV, and 144 mV at 10 mA cm−2, respectively, in alkaline (pH = 14), acidic (pH = 0), and neutral (pH = 7) electrolytes. [Display omitted] • Three-shell structure is built by coating and step-by-step phosphating strategy. • The structure enriches active sites and shortens electrolyte diffusion channels. • More defect structures are formed during the O and P exchange process. • Excellent hydrogen evolution performances are achieved over a wide pH range. The development of highly effective non-precious metal catalysts with high intrinsic activity and rich accessible catalysis centers are the relentless goals of the scientific community to lower energy consumption and production cost. In this work, a unique triple-shell CoP@CoP@(Co/Ni) 2 P hollow structure with rich defect structure has been successfully constructed, which presents remarkable activity against HER over a wide pH range. The overpotentials of 147 mV, 139 mV, and 144 mV are achieved at 10 mA cm−2 current density for CoP@CoP@(Co/Ni) 2 P in 1 M KOH, 0.5 M H 2 SO 4 , and 1 M phosphate-buffered saline (PBS) conditions, respectively. The excellent HER activity of CoP@CoP@(Co/Ni) 2 P can be attributed to their multi-shell hollow structure for abundant activity centers, and rich defect structure for the enhanced intrinsic activity. This work provides new insights into the design and synthesis of multi-shell hollow structures with diverse compositions and defect-rich catalysts for energy storage and conversion application. [ABSTRACT FROM AUTHOR]

Industrial application of electrochemical hydrogen production urgently requires the development of highly efficient, stable, and inexpensive electrocatalysts that can drive a large current density. Here, Ag@Pt icosahedral nanocrystals (Ag@Pt icosahedral NCs) catalysts were successfully prepared through one-step solvothermal synthesis for addressing those challenges. The synergies of geometric effect and electronic effect triggered by the discrepancy of different components greatly enhance the electrocatalytic performance in the hydrogen evolution reaction (HER) process at large current densities over wide pH ranges. Excitingly, the Ag@Pt icosahedral NCs could reach 4000 mA cm−2 at 232 mV under the acidic medium and also showed efficient catalytic activity in 1 M KOH and 1 M phosphate buffered saline (PBS) media, improving their potential application in industrialization. Density functional theory (DFT) calculation results show that the electronic synergistic effect brought by the core-shell structure weakens the optimal free energy of hydrogen adsorption (ΔG H*), promoting the water decomposition kinetics and greatly achieving high catalytic performance. Ag@Pt icosahedral nanocrystals with Ag@Pt solid solution interface and geometric effect exhibit significantly outstanding HER activity and remarkable long-term stability at high current densities over a wide pH range. [Display omitted] • Ag@Pt icosahedral nanocrystals used Na 2 SO 4 as the structural directing agent. • Solid solution thickness of 0.51 nm between the interface of Ag core and Pt shell. • Ag@Pt icosahedral nanocrystals exhibit superior HER performance over wide pH ranges. [ABSTRACT FROM AUTHOR]

[Display omitted] • The CoRu/NC-700 electrocatalyst was synthesized with ZIF-67 as precursor. • CoRu/NC-700 exhibits excellent HER performance and stability in the wide range of pH. • Pyridinic N synergistically enhanced the HER activity of CoRu alloy nanoparticals. The construction of efficient pH-universal hydrogen evolution reaction (HER) electrocatalysts remain enormous challenges for hydrogen production from water electrolysis. Herein, we reported a HER electrocatalyst composed of cobalt-ruthenium alloy nanoparticles with the synergy of pyridinic N (CoRu/NC-700). CoRu/NC-700 exhibits excellent HER performance and stability in acidic, alkaline and neutral media, and can reach 10 mA cm−2 with overpotential of only 6, 10 and 30 mV, respectively. Especially in alkaline and acidic media, overpotential of only 217 and 227 mV are required to achieve 1000 mA cm−2, respectively, which is of great significance for industrialized hydrogen produced by electrolysis of water. KSCN and H 3 PO 4 poisoning experiments prove that such high HER activity is attributed to the synergistic enhancement effect of pyridinic N on CoRu nanoparticles. This work will lay the foundation for the designing and development of novel and efficient pH-universal HER electrocatalysts. [ABSTRACT FROM AUTHOR]

The development of phosphide-based electrocatalyst with excellent properties and good stability under both acidic and alkaline condition is the hotspot of recent research. Herein, we synthesized N doped CoP coated with carbon nanotubes (CoP@NC) electrocatalyst for hydrogen evolution reaction (HER), in which, the ZIF-67 (ZIF = zeolite imidazole skeleton) nanoparticles wrapped Co-MOF (MOF = metal-organic skeleton) nanorods has been used as precursor. The improvement of catalytic performance of N-doped CoP can be attributed to the fact that the introduction of N can optimize the electronic structure and the in-situ grown carbon nanotubes can improve charge transfer rate and avoid the agglomeration of active units. In addition, the effect of phosphorization temperature and the amount of carbon nanotube on the electrochemical activity of the samples were also investigated, and the obtained CoP@NCs only required low overpotential of 250 mV and 234 mV to drive the current density of 100 mA cm−2 under acidic and basic conditions, respectively. This work opens up an efficient paradigm for optimizing the performance of electrocatalysts. • N doped CoP coated with carbon nanotubes (CoP@NC) has been synthesized. • The in-situ formed carbon nanotubes could efficiently improve the charge transfer rate. • The use of Co-MOF in the core part could efficiently the accumulation of active phase. • The carbonization atmosphere has an obviously effect on the electrocatalytic performance. [ABSTRACT FROM AUTHOR]

Developing efficient, novel and pH-universal electrocatalysts toward hydrogen evolution reaction (HER) is a challenging and meaningful task for the large-scale and practical hydrogen application via electrocatalytic overall water-splitting. Herein, we propose one-pot strategy to prepare MoP and Ru 2 P nanoparticles supported on N, P co-doped carbon (MoP-Ru 2 P/NPC) with porous nanostructures. Benefiting from overly specific characters, the synthetical MoP-Ru 2 P/NPC displays low overpotentials of 47 mV, 126 mV and 82 mV to obtain 10 mA cm−2 in alkaline, neutral and acid electrolytes as well as remarkable stability. Moreover, a low cell voltage (1.49 V) is required to spur 10 mA cm−2 for full water-splitting in 1 M KOH with the MoP-Ru 2 P/NPC and commercial NiFe foam as the cathode and anode, respectively. Remarkably, the intermittent sustainable energies, including wind, solar and thermal energies, can drive hydrogen generation directly and then stored them accordingly. One-pot strategy to prepare MoP and Ru 2 P nanoparticles supported on N, P co-doped carbon (MoP-Ru 2 P/NPC) with impressive HER activities in wide pH value and stability. [Display omitted] • Facile and industrially compatible approach is developed to synthesize highly-efficient electrocatalyst. • The coupling effects of bimetallic phosphide and specific porous nanostructure enhanced the electrocatalytic HER performance. • The designed MoP-Ru 2 P/NPC presents excellent catalytic performance toward HER in full pH range. • The overall water-splitting can be powered by sustainable energies, including solar, wind and thermal energies. [ABSTRACT FROM AUTHOR]