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Binder plays a crucial role in constructing high‐performance electrodes for water electrolysis. While most research has been focused on advancing electrocatalysts, the application of binders in electrode design has yet to be fully explored. Herein, the in situ incorporation of polytetrafluoroethylene (PTFE) as a multifunctional binder, which increases electrochemical active sites, enhances mass transfer, and strengthens the mechanical and chemical robustness of oxygen evolution reaction (OER) electrodes, is reported. The NiFe‐LDH@PTFE/NF electrode prepared by co‐deposition of PTFE with NiFe‐layered double hydroxide onto nickel foam demonstrates exceptional long‐term stability with a minimal potential decay rate of 0.034 mV h−1 at 500 mA cm−2 for 1000 h. The alkaline water electrolyzer utilizing NiFe‐LDH@PTFE/NF requires only 1.584 V at 500 mA cm−2 and sustains high energy efficiency over 1000 h under industrial operating conditions. This work opens a new path for stabilizing active sites to obtain durable electrodes for OER as well as other electrocatalytic systems. [ABSTRACT FROM AUTHOR]

Abstract Binder plays a crucial role in constructing high‐performance electrodes for water electrolysis. While most research has been focused on advancing electrocatalysts, the application of binders in electrode design has yet to be fully explored. Herein, the in situ incorporation of polytetrafluoroethylene (PTFE) as a multifunctional binder, which increases electrochemical active sites, enhances mass transfer, and strengthens the mechanical and chemical robustness of oxygen evolution reaction (OER) electrodes, is reported. The NiFe‐LDH@PTFE/NF electrode prepared by co‐deposition of PTFE with NiFe‐layered double hydroxide onto nickel foam demonstrates exceptional long‐term stability with a minimal potential decay rate of 0.034 mV h−1 at 500 mA cm−2 for 1000 h. The alkaline water electrolyzer utilizing NiFe‐LDH@PTFE/NF requires only 1.584 V at 500 mA cm−2 and sustains high energy efficiency over 1000 h under industrial operating conditions. This work opens a new path for stabilizing active sites to obtain durable electrodes for OER as well as other electrocatalytic systems.

A high-current-density terahertz electron-optical system based on a carbon nanotube (CNT) cold cathode has been investigated in order to solve notable mode competition in high-order harmonic gyrotrons. Simulation results show that a near-axis electron beam can be generated, with a beam current of 160 mA at an accelerating voltage of 23.5 kV. The source supports the electron beam with a velocity ratio of 1.1 and a guiding center radius of 57~μm. A narrow beam spatial distribution is evidenced by adjusting control anode voltage, satisfying the need for high operating current density in slow wave devices. The current density of the electron beam is up to 620 A/cm2 at the output port and the velocity ratio is 0.44, with parallel energy accounting for 84% of the total energy. [ABSTRACT FROM AUTHOR]

Multiphasic fish-gill-like NiCoP@Co 0.5 Ni 0.5 Se 2 heterostructure with an extremely high stability is fabricated as high performance electrocatalyst for high current density hydrogen evolution. This work provides an innovative approach to efficient electrocatalysts of industrial potential. [Display omitted] • A fish-gill-like heterostructure NiCoP@Co 0.5 Ni 0.5 Se 2 /NF is created. • Water and hydrogen adsorption kinetics are optimized. • NiCoP@Co 0.5 Ni 0.5 Se 2 /NF achieves a high-current-density of 671 mA cm−2 at 250 mV. • An excellent overall water splitting performance is realized. Multiphasic engineering is powerful to improve the performance of hydrogen evolution. Here, NiCoP@Co 0.5 Ni 0.5 Se 2 heterostructure with a fish-gill-like morphology has been initially prepared via an epitaxial controlled growth strategy. When used as catalyst in the hydrogen evolution, this heterostructure gives low overpotential of 235 mV and long-term durability of 100 h at high current density of 500 mA cm−2 in 1.0 M KOH, showing a superior activity and excellent stability. Such superior performances are achieved by its 3D multiphasic heterostructure and optimized interface electronic structure because extremely porous superhydrophilic and superaerophobic surface of hierarchical morphology enhance kinetic of hydrogen evolution. The findings reported in this work open new occasion for creating novel technologies based on nature-inspired strategy and multiphasic engineering, as evidenced by a superior overall water splitting performance of an assembled NiCoP@Co 0.5 Ni 0.5 Se 2 /NF‖NiFe-LDH/NF cell under industrial condition (30 % KOH, 25 and 60 °C). [ABSTRACT FROM AUTHOR]

Powerful, efficient, and corrosion-resistant electrocatalysts are in need to achieve high-current-density neutral seawater hydrogen evolution. Here, a novel strategy through strong metal-support interaction (SMSI) and incorporation of Pt to construct PtNb-Nb 2 O 5 clusters @C was developed with stable high-current-density neutral seawater hydrogen evolution property for the first time. SMSI prevents agglomeration and corrosion of nanomaterials. Pt sites were proposed to play an anabranch role by binding H* to stabilize the Nb valence state and prevent water dissociation incapacitation. The optimized PtNb-Nb 2 O 5 @CC delivers low overpotentials of 440 mV (500 mA cm−2) and 570 mV (1000 mA cm−2) in neutral seawater and has 360 h excellent durability at 500 mA cm−2. In-situ Fourier transform infrared spectroscopy (FTIR), in-situ Raman spectroscopies and theoretical calculations supported the hydrogen evolution reaction (HER) mechanism. PtNb-Nb 2 O 5 heterogeneous interface provided more active sites for water dissociation. OH* adsorbed on Nb sites in stable Nb 2 O 5 , and H* adsorbed on Nb sites and desorbed as H 2 on Pt sites in stable PtNb. Overall, this work not only first achieves stable high-current-density neutral seawater hydrogen evolution property, but also opens a new opportunity to explore SMSI and incorporation of Pt to prevent agglomeration, corrosion, and water dissociation incapacitation for catalytic applications under high current densities. [Display omitted] • A novel strategy through strong metal-support interaction and incorporation of Pt was proposed. • This strategy can prevent agglomeration, corrosion and water dissociation incapacitation. • PtNb-Nb 2 O 5 clusters @C was synthesized by solvent-free microwave method. • Stable high-current-density neutral seawater hydrogen evolution property was achieved. • In-situ characterizations and theoretical calculations demonstrate the reaction mechanism. [ABSTRACT FROM AUTHOR]