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Engineering the reaction interface to preferentially attract reactants to inner Helmholtz plane is highly desirable for kinetic advancement of most electro-catalysis processes, including hydrogen evolution reaction (HER). This, however, has rarely been achieved due to the inherent complexity for precise surface manipulation down to molecule level. Here, we build a MoS 2 di-anionic surface with controlled molecular substitution of S sites by –OH. We confirm the –OH group endows the interface with reactant dragging functionality, through forming strong non-covalent hydrogen bonding to the reactants (hydronium ions or water). The well-conditioned surface, in conjunction with activated sulfur atoms (by heteroatom metal doping) as active sites, giving rise to up-to-date the lowest over potential and highest intrinsic activity among all the MoS 2 based catalysts. The di-anion surface created in this study, with atomic mixing of active sites and reactant dragging functionalities, represents a effective di-functional interface for boosted kinetic performance. H 2 energy as an alternative to fossil fuels requires cost-effective catalysts with fast kinetics for splitting water. Here, authors design MoS 2 materials with di-anionic surfaces to improve the electrocatalytic H 2 evolution activities.

The poor stability of Ru-based acidic oxygen evolution (OER) electrocatalysts has greatly hampered their application in polymer electrolyte membrane electrolyzers (PEMWEs). Traditional understanding of performance degradation centered on influence of bias fails in describing the stability trend, calling for deep dive into the essential origin of inactivation. Here we uncover the decisive role of reaction route (including catalytic mechanism and intermediates binding strength) on operational stability of Ru-based catalysts. Using MRuO x (M = Ce 4+ , Sn 4+ , Ru 4+ , Cr 4+ ) solid solution as structure model, we find the reaction route, thereby stability, can be customized by controlling the Ru charge. The screened SnRuO x thus exhibits orders of magnitude lifespan extension. A scalable PEMWE single cell using SnRuO x anode conveys an ever-smallest degradation rate of 53 μV h −1 during a 1300 h operation at 1 A cm −2 . The poor stability of ruthenium-based catalysts has greatly hampered their application in polymer electrolyte membrane water electrolysis. Here, the authors uncover the decisive role of reaction route on catalytic performance, which enables the screening of efficient ruthenium-based water oxidation catalysts.

Lacking strategies to simultaneously address the intrinsic activity, site density, electrical transport, and stability problems of chalcogels is restricting their application in catalytic hydrogen production. Herein, we resolve these challenges concurrently through chemically activating the molybdenum disulfide (MoS 2 ) surface basal plane by doping with a low content of atomic palladium using a spontaneous interfacial redox technique. Palladium substitution occurs at the molybdenum site, simultaneously introducing sulfur vacancy and converting the 2H into the stabilized 1T structure. Theoretical calculations demonstrate the sulfur atoms next to the palladium sites exhibit low hydrogen adsorption energy at –0.02 eV. The final MoS 2 doped with only 1wt% of palladium demonstrates exchange current density of 805 μA cm −2 and 78 mV overpotential at 10 mA cm −2 , accompanied by a good stability. The combined advantages of our surface activating technique open the possibility of manipulating the catalytic performance of MoS 2 to rival platinum. While water reduction may provide a carbon-neutral means to produce hydrogen gas, there is a scarcity of efficient, earth-abundant electrocatalysts. Here, the authors add palladium into MoS 2 materials to activate and stabilize the conductive basal plane to improve the electrocatalytic activity.

Engineering an electrocatalytic anode material to boost reaction kinetics is highly desirable for the anodic oxygen evolution reaction (OER), which is the major obstacle for high efficiency water electrolysis. Here, we present a novel kind of Zn-doped Co3O4 hollow dodecahedral electrocatalyst. Abundant oxygen vacancy defects are introduced due to the incorporation of Zn2+, which is beneficial for OH− adsorption and the charge transfer reaction during the OER process. Moreover, the increase in surface area caused by the advanced structure of the hollow porous dodecahedra facilitates mass transport by increasing the surface area. The novel strategy proposed in this study provides an efficient way to design high-performance electrocatalysts for water electrolysis.Water splitting: A dodecahedral catalystA cheap catalyst that aids water splitting and is made from readily available materials has been developed by researchers in China. Hydrogen releases energy when burned in air, and is therefore a promising source of clean power. Hydrogen can be sourced by splitting water into its constituent atoms, but the chemical reaction separating hydrogen and oxygen, known as the oxygen evolution reaction, is not particularly efficient. Yao Xiao and coworkers from the Changchun Institute of Applied Chemistry developed an oxygen evolution reaction electrocatalyst made from zinc-doped cobalt oxide, Zn-Co3O4. The catalyst has a unique dodecahedral structure, and the team believes it is its large surface area that is responsible for its excellent performance. Unlike many other water-splitting catalysts, the constituent materials of Zn-Co3O4 are cheap and readily available.

The limited durability of metal-nitrogen-carbon electrocatalysts severely restricts their applicability for the oxygen reduction reaction in proton exchange membrane fuel cells. In this study, we employ the chemical vapor modification method to alter the configuration of active sites from FeN 4 to the stable monosymmetric FeN 2 +N’ 2 , along with enhancing the degree of graphitization in the carbon substrate. This improvement effectively addresses the challenges associated with Fe active center leaching caused by N-group protonation and free radicals attack due to the 2-electron oxygen reduction reaction. The electrocatalyst with neoteric active site exhibited excellent durability. During accelerated aging test, the electrocatalyst exhibited negligible decline in its half-wave potential even after undergoing 200,000 potential cycles. Furthermore, when subjected to operational conditions representative of fuel cell systems, the electrocatalyst displayed remarkable durability, sustaining stable performance for a duration exceeding 248 h. The significant improvement in durability provides highly valuable insights for the practical application of metal-nitrogen-carbon electrocatalysts. The limited durability of metal-nitrogen-carbon electrocatalysts hinders their use in proton exchange membrane fuel cells for the oxygen reduction reaction. Here the authors transform active sites from FeN4 to stable monosymmetric FeN2 + N’2 via chemical vapor modification, resulting in enhanced improving the durability of the catalyst.

Designing feasible electrocatalysts towards oxygen reduction reaction (ORR) requires advancement in both activity and stability, where attaining high stability is of extreme importance as the catalysts are expected to work efficiently under frequent startup/shut down circumstances for at least several thousand hours. Alloying platinum with early transition metals (i.e., Pt—La alloy) is revealed as efficient catalysts construction strategy to potentially satisfy these demands. Here we report a Pt 5 La intermetallic compound synthesized by a novel and facile strategy. Due to the strong electronic interactions between Pt and La, the resultant Pt 5 La alloy catalyst exhibits enhanced activity with half wave of 0.92 V and mass activity of 0.49 A·mg Pt −1 , which strictly follows the 4e transfer pathway. More importantly, the catalyst performs superior stability during 30,000 cycles of accelerated stressed test (AST) with mass activity retention of 93.9%. This study provides new opportunities for future applications of Pt-rare earth metal alloy with excellent electrocatalytic properties.

For the goal of practical industrial development of fuel cells, cheap, sustainable and high performance electrocatalysts for oxygen reduction reactions (ORR) which rival those based on platinum (Pt) and other rare materials are highly desirable. In this work, we report a class of cheap and high-performance metal-free oxygen reduction electrocatalysts obtained by co-doping carbon blacks with nitrogen and fluorine (CB-NF).The CB-NF electrocatalysts are highly active and exhibit long-term operation stability and tolerance to poisons during oxygen reduction process in alkaline medium. The alkaline direct methanol fuel cell with the best CB-NF as cathode (3 mg/cm 2 ) outperforms the one with commercial platinum-based cathode (3 mg Pt /cm 2 ). To the best of our knowledge, these are among the most efficient non-Pt based electrocatalysts. Since carbon blacks are 10,000 times cheaper than Pt, these CB-NF electrocatalysts possess the best price/performance ratio for ORR and are the most promising alternatives to Pt-based ones to date.

Fe/N/C material is the most competitive alternative to precious-metal catalysts for oxygen reduction. In view of the present consensus on active centers, further effort is directed at maximizing the density of single Fe atoms. Here, the imperfections in commonly used doping strategy of Fe for the synthesis of zeolitic imidazolateframework (ZIF)-derived Fe/N/C catalysts are revealed. More importantly, a strikingly improved catalyst is obtained by a ‘second pyrolysis’ method and delivers a half-wave potential of 0.825 V (vs. RHE) in acidic media. The strong confinement effect of carbonaceous host accounts for the formation of dense single-atom sites and thus the high activity. Our findings will potentially facilitate future improvement of M/N/C catalysts.

In this study, phosphorus doped graphene supported PtNiP nanocluster electrocatalyst (PtNiP/P-graphene) was successfully prepared via a simple hypophosphite-assisted co-reduction method. The improved anchoring force and increased anchoring sites of graphene support result from phosphorus doping as well as size-confined growth effect of NaH 2 PO 2 leads to uniform dispersion of ultrafine PtNiP nanoclusters. Doped P also promotes the removal of CO-like intermediate by adjusting Pt electronic structure combining with alloyed Ni via electronic effects. As a result, the as-prepared PtNiP/P-graphene catalyst with more exposed active sites and optimized electronic structure of Pt alloy shows excellent electrocatalytic performances for methanol oxidation reaction (MOR) both in activity and durability in an acidic medium.

The inherent scaling relationships between adsorption energies of oxygen-containing intermediates impose an intrinsic limitation on the maximum oxygen reduction reaction (ORR) activity, which represents one of the bottlenecks for the practical application of anion exchange membrane fuel cells (AEMFCs). To address this challenge, we align the 3 dz 2 orbital energy levels of Fe and Co to selectively customize the dissociative ORR pathway without the formation of OOH* intermediates, circumventing the conventional OH*-OOH* scaling relations. This rational design is achieved by atomic phosphorus(P) substitution, which not only optimizes orbital matching towards O-O cis-bridge adsorption, but also stabilizes the spontaneously adsorbed OH ligand as an electronic modifier. Due to these attributes, the well-designed FeCo-N/P-C catalyst demonstrates ORR performance with a current density of 251 mA·cm -2 at 0.9 V iR-free under 1.5 bar H 2 -O 2 , showing a competitive performance with state-of-the-art Pt-free electrocatalysts and meeting the 2025 DOE target (44 mA·cm -2 ). More importantly, the peak power density reaches as high as 0.805 W·cm -2 under 1.5 bar H 2 -air with negligible degradation observed over 10,000 cycles of voltage accelerated stress testing. This work offers a highly competitive electrocatalyst for AEMFCs and opens an effective avenue to bypass the constraints of linear scaling relations for ORR and beyond. The inherent scaling relationships among the adsorption energies of intermediates limit the efficiency of oxygen electrocatalysis. Here, a dual-atom catalyst with aligned orbital energy level is developed, driving the dissociative pathway to bypass scaling relationships towards enhanced performance.