Search

Currently, the construction of heterostructures to optimize electrocatalytic activities is a hot research topic, since there is still a certain gap between the electrocatalytic properties of these heterostructures and that of Pt/C. With this in mind, we utilized in‐situ vapor‐phase phosphorization‐sulfurization to obtain the CoP3/MoS2−Co0.75Mo3S3.75 (CoP/CoMoS, for short) heterostructure on carbon cloth (CC), which exhibits Pt‐like electrocatalytic performance and excellent stability in acid electrolyte. Activated by CoP3 active phase, the electronic configuration of CoMoS and the adsorption energy of H* (▵GH*) are greatly optimized. Meanwhile, the rapid oxidation of CoMoS phase can be effectively avoided under the protection of CoP3 layer. This work provides a reference for the design of heterostructures and their mechanism of action in electrocatalysis. [ABSTRACT FROM AUTHOR]

Transition metal phosphide is regarded as one of the most promising candidates to replace noble‐metal hydrogen evolution reaction (HER) electrocatalysts. Nevertheless, the controllable design and synthesis of transition metal phosphide electrocatalysts with efficient and stable electrochemical performance are still very challenging. Herein, a novel hierarchical HER electrocatalyst consisting of three‐dimensional (3D) coral‐like Mn‐doped Co2P@an intermediate layer of Ni2P generated in situ by phosphorization on Ni foam (MnCoP/NiP/NF) is reported. Notably, both the incorporation of Mn and introduction of the Ni2P interlayer promote Co atoms to carry more electrons, which is beneficial to reduce the force of the Co−H bond and optimize the adsorption energy of hydrogen intermediate (|ΔGH*|), thereby making MnCoP/NiP/NF exhibit outstanding HER performance with onset overpotential and Tafel slope as low as 31.2 mV and 61 mV dec−1, respectively, in 1 m KOH electrolyte. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts (SACs) are widely studied in various chemical transformations due to their high catalytic activity and atom utilization. However, modulating the catalytic performance of catalysts by adjusting the microenvironment remains a great challenge. In this paper, a novel master‐double guest vulcanization‐assisted strategy is reported for synthesizing Fe single‐atom catalysts on N,S codoped porous hollow leaf carbon (FeSA/N,S‐PHLC) with highly exposed FeN3SOH sites. Fe(mIm) (guest I) is loaded on the surface of ZIF‐L (host) and then trithiocyanuric acid (TCA, guest II) is bonded with Fe(mIm), and the resulting ZIF‐L@Fe(mIm)@TCA precursors can be converted to FeSA/N,S‐PHLC with controllable structures. In addition, XPS analysis yield an increase in pyridine N content in FeSA/N,S‐PHLC compared to FeSA/N‐PHLC. It can be demonstrated by theoretical calculations that the N,S‐coordinated axially hydroxy‐coordinated asymmetric Fe centers synergistically with the abundance of pyridinic nitrogen facilitate the adsorption and desorption of oxygen intermediates, and the 3d orbitals of the Fe active centers can be optimized. The prepared FeSA/N,S‐PHLC catalyst has a half‐wave potential (E1/2) of 0.91 V under alkaline conditions, and E1/2 = 0.75 V under acidic conditions. It shows excellent cycle stability (882 h) and power density (217 mW cm−2) in the assembly of zinc–air battery (ZABs) devices. [ABSTRACT FROM AUTHOR]

It is a great challenge to induce the formation of the RuP4 phase and realize the construction of a metal‐rich phase/phosphorus‐rich phase‐ruthenium phosphide heterostructure by directional regulation of the proportion of P and metal atoms. The ultra‐high conductivity of Ru2P and the excellent ability of V‐doped RuP4 to absorb/desorb H* are confirmed by density functional theory (DFT) calculations, which laid a theoretical foundation for the construction of a unique Ru2P/V‐RuP4 structure to accelerate HER reaction kinetics. This work innovatively uses the V‐doping strategy to induce the formation of RuP4 phase with high intrinsic activity, and finally construct V‐RuxPy nanosheets with rich Ru/Ru2P/V‐RuP4 heterostructures. Thanks to the rich Ru/Ru2P/V‐RuP4 heterostructure and the optimization of V dopants, the V‐RuxPy catalyst only needs 180 mV to obtain an industrial‐grade current density of 1 A cm−2. In summary, this work provides a new idea for the design and performance optimization of ruthenium‐based catalysts. [ABSTRACT FROM AUTHOR]

Rational construction of high‐efficiency and low‐cost catalysts is one of the most promising ways to produce hydrogen but remains a huge challenge. Herein, interface engineering and heteroatom doping were used to synthesize V‐doped sulfide/phosphide heterostructures on nickel foam (V‐Ni3S2/NixPy/NF) by phosphating treatment at low temperature. The incorporation of V can adjust the electronic structure of Ni3S2, expose more active sites, and protect the 3D structure of Ni foam from damage. Meanwhile, the heterogeneous interface formed between Ni3S2 and NixPy can provide abundant active sites and accelerate electron transfer. As a result, the V‐Ni3S2/NixPy/NF nanosheet catalyst exhibits outstanding activity in the hydrogen evolution reaction (HER) with an extremely low overpotential of 90 mV at a current density of 10 mA cm−2 and stable durability in alkaline solution, which exceeds those most of the previously reported Ni‐based materials. This work shows that rational design by interfacial engineering and metal‐atom incorporation has a significant influence for efficient hydrogen evolution. [ABSTRACT FROM AUTHOR]