Bin Wu

Developing high-performance, cost-effective oxygen reduction electrocatalysts is essential for advancing zinc-air batteries and anion-exchange membrane fuel cells. Here, we report a MnP/Cu3P heterojunction encapsulated in nitrogen-doped carbon that addresses this challenge through an integrated electronic-structure-to-hydration engineering strategy. Spectroscopic and DFT analyses consistently reveal spontaneous electron transfer from Cu3P to MnP across the heterointerface, which reduces the work function and homogenizes the surface charge distribution. This charge homogenization weakens K+ enrichment at the inner Helmholtz plane, triggering a potential-driven restructuring of the interfacial water network from rigid, strongly hydrogen-bonded clusters to a flexible, weakly hydrogen-bonded 2-HB architecture, as evidenced by in situ ATR-SEIRAS. This adaptive water network serves as an efficient proton relay that stabilizes the *OOH intermediate via bidentate hydrogen bonding and facilitates *OH desorption, collectively lowering the kinetic barrier of the rate-determining step. Benefiting from this mechanism, the catalyst achieves outstanding ORR activity with a half-wave potential of 0.84 V and a Tafel slope of 50.7 mV dec–1. In ZABs and AEMFCs, it delivers exceptional power densities and robust durability, substantially outperforming most non-precious metal benchmarks. This work establishes the electronic-structure-to-hydration linkage as a new paradigm for electrocatalyst design beyond conventional electronic optimization.

Phase engineering has proved effective in enhancing electrocatalytic performance by precisely controlling crystal structures. While significant efforts have been dedicated to phase regulation of active metals, the role of crystal phase of catalyst supports in steering the hydrogen migration during hydrogen evolution reaction (HER) remains underexplored. This work systematically investigates zirconium dioxide in its monoclinic ( m -ZrO ₂ ) and tetragonal ( t -ZrO ₂ ) phases as supports for Ru nanoclusters. A combination of spectroscopy and theoretical calculation demonstrates strong electronic metal–support interactions and work function difference between Ru and m -ZrO ₂ lead to interfacial charge accumulation, accelerated water dissociation, and reverse hydrogen spillover, significantly enhancing electrocatalytic HER performance in alkaline medium. The Ru@ m -ZrO ₂ /C catalyst exhibits excellent HER activity in different electrolytes. It achieves 10 mA cm ⁻² with an extremely low overpotential (η ₁₀ ) of only 28 mV in 1 M KOH, delivering a mass activity of 2.72 A mg _Ru ⁻¹ (at 50 mV overpotential), which is 45 times higher than that of commercial Pt/C. The η ₁₀ values are 56, 42, and 30 mV in 0.5 M H ₂ SO ₄ , 1 M KOH + 2 M NaCl, and 1 M KOH + simulated seawater, respectively. Furthermore, the catalyst also demonstrates excellent stability under alkaline simulated seawater electrolysis conditions. When integrated into an anion-exchange membrane water electrolyzer, it achieves 1.0 A cm ⁻² at 1.76 V with stability exceeding 300 h. This work underscores the pivotal importance of support phase engineering for designing high-performance electrocatalysts for water splitting.

Alkaline hydrogen oxidation reaction (HOR) kinetics are fundamentally governed by electrode-electrolyte interfacial water structure and hydrogen-bond (H-bond) networks, yet their dynamic regulatory mechanism remains elusive. Here we show that precise modulation of the P coordination environment of Ir-based catalysts effectively enhances alkaline HOR catalytic performance. A series of Ir-based model catalysts with tunable P-coordination numbers are synthesized on nitrogen-doped carbon (NC) (IrP₂-Ir₂P@NC, IrP₂@NC, Ir@NC). The optimal Ir-P coordination (5.1 ± 0.7) induces controlled partial dissolution of Ir cations, a dynamic phenomenon rarely exploited in alkaline HOR catalysis. This effect reconstructs the interfacial H-bond network via enriched gap-H₂O and strengthened network connectivity, while optimizing hydrogen and hydroxyl adsorption to accelerate the Volmer step. The optimized IrP₂-Ir₂P@NC delivers a mass activity of 1.72 mA μg⁻¹ and a prominent alkaline exchange membrane fuel cell (AEMFC) peak power density of 1.59 W cm⁻². Ab initio molecular dynamics simulations confirm modified solvation structure elevates interfacial H-bond density, thereby elucidating the previously unresolved mechanism by which cation dissolution dynamically templates the H-bond network for enhanced HOR performance.

Electrochemical water splitting stands as a feasible approach for sustainable hydrogen production, but its industrial implementation is restricted by sluggish oxygen evolution reaction (OER) kinetics and excessive dependence on freshwater resources. As a widely existing alternative, seawater contains a high concentration of chloride ions (Cl⁻), which give rise to serious electrode corrosion and catalyst deactivation, bringing great challenges to actual electrolysis applications. Herein, we report a facile room-temperature two-step soaking strategy to fabricate sulfur-modified NiFe layered double hydroxide (S-NiFe-LDH) catalysts for efficient OER in both alkaline freshwater and seawater electrolytes. The introduction of sulfur not only optimizes the electronic structure of NiFe-LDH to strengthen intrinsic catalytic activity and speed up charge transfer, but also promotes the formation of a Cl⁻-resistant layer, thus significantly improving corrosion resistance. In addition, DFT calculations show sulfur modification in NiFe layered double hydroxide upshifts the O 2p-band center to activate lattice oxygen, switches the oxygen evolution reaction pathway to the lattice oxygen mechanism with reduced thermodynamic barriers, and realizes the selective adsorption of OH⁻ over Cl⁻. As a result, the as-prepared S-NiFe-LDH catalyst exhibits exceptional OER performance, requiring overpotentials (η) of 250, 270, and 290 mV to reach current densities of 50, 100, and 200 mA·cm⁻² in 1 M KOH, respectively, with a Tafel slope of 22.3 mV·dec⁻¹. Moreover, it maintains remarkable stability for more than 200 h in alkaline seawater electrolytes and achieves nearly 100% Faradaic efficiency for water splitting, effectively avoiding the parasitic chlorine evolution reaction (CER). This work provides a scalable and energy-efficient synthetic route for designing advanced non-noble metal catalysts, paving the way for industrial-scale hydrogen production from seawater.

Modulating electronic spin states of metal active centers is an effective strategy to address the sluggish oxygen evolution reaction (OER) kinetics. Herein, we utilize a dual‐ligand competitive coordination strategy to induce lattice expansion, generate abundant oxygen vacancies and unsaturated coordination sites, and restructure the NiO ₆ octahedron. This triggers a pivotal transition of Ni from intermediate‐spin (Ni ²⁺ ) to high‐spin (Ni ³⁺ ) states, which enhances adsorption of OH ⁻ and oxygen‐containing intermediates, but also tailors the interfacial microenvironment by enriching free water, thus accelerating OER kinetics. In situ x‐ray adsorption spectroscopy further verifies the accelerated adsorption and transformation of oxygen intermediates enabled by this spin reconfiguration. Consequently, the optimized nickel‐thiophene‐2,5‐dicarboxylic acid _0.6 ‐1,4‐dicarboxybenzene _0.4 dual‐ligand metal‐organic framework catalyst (marked as Ni‐TDC _0.6 BDC _0.4 ) delivers excellent OER performance (230 mV@10 mA cm ⁻² ). Using Ni‐TDC _0.6 BDC _0.4 as the anode, the assembled anion exchange membrane water electrolyzer achieves a low cell voltage of 2.40 V at 1.5 A cm ⁻² and maintains stability for 500 h at 300 mA cm ⁻² . Its photovoltaic‐integrated overall water splitting device also attains a 13.23% solar‐to‐hydrogen efficiency with robust stability. This work provides an innovative synthesis pathway for designing high‐performance OER electrocatalysts by tailoring electron spin states.

Modulating electronic spin states of metal active centers is an effective strategy to address the sluggish oxygen evolution reaction (OER) kinetics. Herein, we utilize a dual‐ligand competitive coordination strategy to induce lattice expansion, generate abundant oxygen vacancies and unsaturated coordination sites, and restructure the NiO ₆ octahedron. This triggers a pivotal transition of Ni from intermediate‐spin (Ni ²⁺ ) to high‐spin (Ni ³⁺ ) states, which enhances adsorption of OH ⁻ and oxygen‐containing intermediates, but also tailors the interfacial microenvironment by enriching free water, thus accelerating OER kinetics. In situ x‐ray adsorption spectroscopy further verifies the accelerated adsorption and transformation of oxygen intermediates enabled by this spin reconfiguration. Consequently, the optimized nickel‐thiophene‐2,5‐dicarboxylic acid _0.6 ‐1,4‐dicarboxybenzene _0.4 dual‐ligand metal‐organic framework catalyst (marked as Ni‐TDC _0.6 BDC _0.4 ) delivers excellent OER performance (230 mV@10 mA cm ⁻² ). Using Ni‐TDC _0.6 BDC _0.4 as the anode, the assembled anion exchange membrane water electrolyzer achieves a low cell voltage of 2.40 V at 1.5 A cm ⁻² and maintains stability for 500 h at 300 mA cm ⁻² . Its photovoltaic‐integrated overall water splitting device also attains a 13.23% solar‐to‐hydrogen efficiency with robust stability. This work provides an innovative synthesis pathway for designing high‐performance OER electrocatalysts by tailoring electron spin states.