Binding energies of adsorbed CO and H are key descriptors governing the activity and selectivity of the co-electrolysis of CO2 and H2O to produce syngas with desired CO/H2 ratios. Palladium hydride (PdH), which forms in situ at negative overpotentials, has been identified as the active Pd phase for CO2 reduction to syngas. Herein, binding energies of CO and H are determined using temperature programmed desorption (TPD) of CO and H2 from Pd(111), PdH/Pd(111), and Cu/PdH/Pd(111) under ultra-high vacuum (UHV) conditions. TPD results reveal that desorption of H2 from subsurface PdH occurs at 460 K, while desorption from surface PdH is more facile at 320 K. CO desorption temperatures shift 20 K lower on PdH/Pd(111) compared to on Pd(111). The presence of 0.7 ML Cu further increases the desorption temperature of H2 by 30 K while simultaneously reducing CO desorption temperatures by 70 K. Density functional theory (DFT) calculations show that CO adsorption onto Pd sites is hindered on the 0.7 ML Cu/PdH/Pd(111) surface while the kinetic barrier for H2 desorption is increased. The trends in the binding energies of CO and H on model surfaces are consistent with electrochemical measurements of CuPd powder catalysts in a membrane electrode assembly (MEA), where H2 evolution is reduced while CO production is enhanced compared to unmodified Pd catalysts. Overall, the results from model surface studies (TPD and DFT) provide a prediction and explanation for the activity and CO/H2 ratios observed in electrochemical experiments. This study also demonstrates that CuPd is a promising catalyst with reduced Pd-loading to produce CO-rich syngas.

Gas-driven element redistribution, characterized by the preferential enrichment of one element at the surface relative to the bulk, is frequently observed in multicomponent alloys. Using L10-ordered PtNi as a model system, we reveal that gas pressure plays a critical role in governing adsorption-driven surface composition during annealing in reducing gases: low pressure favors Pt surface segregation, while high pressure facilitates Ni surface enrichment. In this study, we developed a high-pressure nitriding (HPN) strategy that modulates the surface structure and composition of PtNi catalysts. The resulting HPN-PtNi exhibits enhanced performance and durability in membrane electrode assemblies for heavy-duty fuel cell applications, maintaining a high current density of 1.19 A cm-2 at 0.7 V after 90,000 voltage cycles. Through a combination of experimental and theoretical analyses, we reveal that the HPN process forms additional stabilizing Ni-N bonds and induces elemental redistribution with Ni surface enrichment and a Ni-deficient Pt subsurface. These modifications alter the atomic coordination environment of the ordered PtNi phase. This work presents a generalizable strategy to design robust and high-performing Pt-based catalysts by controlling gas-pressure-driven elemental redistribution and dopant incorporation.

Electrification of chemical production using renewable energy and abundant feedstocks offers a promising pathway for decarbonizing the chemical industry. Current efforts on CO2 valorization largely focus on making chemicals and fuels. To help achieve net-negative emissions through long-term carbon storage, this study aims to develop efficient electrocatalysts for a tandem electrochemical-thermochemical process to convert CO2 into carbon nanofibers (CNFs). CO2 and water are first electrochemically reduced in a membrane electrode assembly (MEA) electrolyzer to produce syngas (CO + H-2), which is subsequently fed into a thermochemical packed bed reactor to facilitate CNF growth. This work systematically evaluated PdxCu1-x bimetallic electrocatalysts to assess the effect of Pd-Cu alloying on enhancing syngas production while reducing Pd loading. Transmission electron microscopy and Raman spectroscopy confirmed the formation of high-purity, crystalline CNFs, regardless of the syngas composition from the MEA. In situ X-ray absorption spectroscopy and X-ray diffraction measurements revealed that increasing Cu content in the PdxCu1-x alloy progressively inhibited palladium hydride formation, consistent with DFT calculations on the stability of PdxCu1-x under reducing electrochemical potentials.

Binding energies of CO and H are determined using temperature programmed desorption of CO and H 2 from Pd(111), PdH/Pd(111), and Cu/PdH/Pd(111) under ultra-high vacuum conditions and are correlated with electrocatalytic selectivity.

Ni-based metal-organic frameworks (MOFs) are promising non-Pt electrocatalysts, but their alkaline hydrogen evolution reaction (HER) activity is often limited by sluggish interfacial kinetics, insufficient electronic modulation, and restricted water accessibility at the solid-liquid interface. Herein, a Ru-regulated Ni-MOF electrocatalyst directly grown on nickel foam (Ru0.2@Ni-MOF/NF) was constructed through a one-step solvothermal strategy using ligands derived from upcycled waste polyethylene terephthalate (PET). The optimized Ru0.2@Ni-MOF/NF electrode exhibits excellent alkaline HER activity, requiring an ultralow overpotential of 18 mV to reach 10 mA cm−2, and maintains stable operation at high current density. When coupled with a PET-derived NiFe-MOF anode for overall water splitting, the electrolyzer delivers 10 mA cm−2 at a low cell voltage of 1.482 V. Operando DRT analysis, DFT calculations, and MD simulations reveal that Ru incorporation accelerates interfacial relaxation kinetics, induces electron redistribution and electronic-structure modulation, optimizes H* and H2O adsorption energetics, and enhances local water accessibility around Ru-containing interfacial sites. This work provides both a sustainable strategy for converting waste PET into value-added electrocatalysts and a mechanistic guideline for designing heterometal-regulated MOF catalysts for alkaline hydrogen production

Ethylene carbonate (EC) and propylene carbonate (PC) are important feedstocks in the production of commercial battery electrolytes and green solvents. However, their conventional industrial synthetic pathways rely heavily on energy-intensive thermocatalytic processes with costly epoxide reactants. Here, we report a class of multifunctional metal-organic framework photocatalysts (RE-BTTD-AC) that integrate oxygen (O2) activation, C-H bond activation, photothermal conversion and Lewis acid reactivity. They enable photosynthesis of EC and PC under ambient conditions with a sustainable, cheap and safe method using ethylene (C2H4)/propylene (C3H6), CO2, and O2. Experimental results combined with theoretical calculations demonstrate that the multifunctional nature of RE-BTTD-AC permits the occurrence of tandem reaction of photoredox and cycloaddition, leading to a relay conversion of C2H4/C3H6-to-epoxide-to-EC/PC. The catalytic system exhibits high product yields (EC of 96.02 μmol/g/h with 95% selectivity, PC of 640.03 μmol/g/h with 93% selectivity) in 48 hours and has a long-term production capacity of at least 720 hours.

Seawater electrolysis alleviates freshwater demand to produce clean hydrogen while eliminating the need for water purification steps. The anodic process, seawater oxidation, typically requires high overpotentials and yields low selectivity to oxygen via the oxygen evolution reaction (OER), primarily due to the competing chlorine evolution reaction (CER) and hypochlorite evolution reaction (HCER) in pH-neutral conditions. Here, combining in situ surface-enhanced Raman characterization, grand canonical density functional theory-based calculations, and kinetic Monte Carlo simulations, we report the evolution of surface adsorbate configurations driven by applied potential and pH during seawater-relevant OER over IrO2, a highly OER-active and chloride-corrosion-resistant catalyst. As a result, the chemical properties of active sites, and thereby the kinetics of OER and CER/HCER, are effectively tuned. However, it is revealed that there is no optimal combination of potential and pH to achieve both high activity and high selectivity for seawater-relevant OER. To address this limitation, we establish a correlation between activity/selectivity and surface adsorbate configurations, enabling the optimization of highly active and OER-selective IrO2-based catalysts in seawater-relevant oxidation by modulating the local adsorbate environment of active sites.

Pt-based catalysts for propane dehydrogenation (PDH) are known to exhibit size-dependent activity, selectivity and stability, but the nature of the active Pt species responsible for size-dependent behavior remains unknown. In this paper, by employing density functional theory, microkinetic modeling as well as kinetic Monte Carlo simulations, we investigate PDH over (i) single Pt atom supported on the Al2O3(1 1 0), (ii) cluster of 13 Pt atoms adsorbed on Al2O3(1 1 0) and (iii) Pt(1 1 1) crystal surface. With decreasing size of Pt species, PDH activity increase, while both propene selectivity and stability against coking precursors exhibit an inverted volcano trend, which indicate the superiority of Pt single-atom catalyst and align closely with relevant experiment. Electronic structure analysis revealed that Pt species transfer electrons to the alumina, resulting in Pt positively charged. The valence electrons of Pt exhibit an inverted volcano relationship with adsorption energies of C3H7—H (activity index), while a volcano relationship with energy difference between propylene desorption and deep dehydrogenation (selectivity and stability index). The size reduction affects the number of electrons transferring, and the loss of relative moderate electrons of supported Pt single-atom, compared with Pt nanocluster and Pt large particle, leads to enhanced PDH activity, selectivity and stability against carbon deposition.

For a high-performance proton exchange membrane water electrolyzer (PEMWE), acidic oxygen evolution reaction (OER) electrocatalysts require highly dispersed iridium oxide (IrO x ) nanoparticles. Although carbon-based materials have been explored as promising supports for IrO x nanoparticles, their limited stability under harsh oxidative and acidic PEMWE conditions remains a significant challenge. In this study, we report the synthesis and in situ characterization of active and durable IrO x electrocatalysts supported on electrochemically stable and electrically conducting tantalum carbide (TaC). When applied in a PEMWE, the IrO x /TaC electrocatalyst achieves a cell voltage of 1.71 V at 1.0 A cm-2, outperforming the commercial IrO2 catalyst (1.82 V at 1.0 A cm-2). Furthermore, the IrO x /TaC catalyst maintains a stable operation for 200 h at 0.5 A cm-2 with a low degradation rate of 36 mu V h-1. Density functional theory calculations further confirm that Ir-O-Ta bond formation at the IrO x /TaC interface reduces the overpotential of the OER compared to IrO2. This study underscores the pivotal role of supporting IrO x over stable and conducting metal carbides, providing guidance for the design of advanced acidic OER catalysts.

The sluggish kinetics and insufficient durability of platinum-based catalysts remain crucial barriers limiting proton-exchange-membrane fuel cells (PEMFCs) deployment. Here, we report a theory-guided synthesis combined with rare-earth templating to realize a previously inaccessible Pt5Co-like phase with tailored atomic-scale strain. Guided by density functional theory (DFT) calculations, we identified that a Pt5Co-like sublayer can induce a unique mild compressive strain (-1.24%) to the Pt(111) shell and an optimal *OH binding energy shift (ΔE ≈ 0.11 eV). This shift positions the alloy catalyst near the apex of the oxygen reduction reaction activity volcano. This prediction guided the synthesis of ternary alloy Pt5(Ce)Co@Pt multilayer nanoparticles, featuring a Ce-stabilized core, a Pt5Co-like sublayer, and a Pt-rich shell. This catalyst demonstrates both exceptionally high activity and durability, achieving a mass activity of 2.6 A∙mgPt -1 in rotating disk electrode testing. In fuel cell membrane electrode assembly tests, Pt5(Ce)Co@Pt achieves a current density of 1.9 A∙cm-2 at 0.7 V under heavy-duty vehicle conditions. Remarkably, it maintains 1.2 A∙cm-2 after 1 80 000 AST cycles, doubling the U.S. DOE 2025 target. This work demonstrates a rational design strategy that DFT-guided strain engineering integrates with rare-earth templating to advance Pt-based catalysts for fuel cell applications.

Monoclinic hafnia stabilizes atomically dispersed indium, creating active interfacial sites to advance selective CO2 conversion to methanol.

Identity of the active sites for carbon dioxide-to-methanol conversion on industrial Cu/ZnO/Al2O3 has long been debated in heterogeneous catalysis. A recent Nature Catalysis study by Lunkenbein and coworkers uses operando transmission electron microscopy to reveal that the catalyst is highly dynamic, cycling among alloyed, oxidized, and encapsulated states during carbon dioxide activation and hydrogenation.

Carbon nanotubes (CNTs) are important materials for electronics and structural composites, but their production still relies on hydrocarbon-based chemical vapor deposition, an energy-intensive and fossil-dependent process, limited by rapid catalyst deactivation. Using CO2 as a carbon feedstock offers a sustainable route for CNT synthesis, yet direct CO2 conversion to CNTs is thermodynamically unfavorable and existing CO2-to-carbon pathways mainly yield amorphous or weakly graphitized solids. Here, we demonstrate a tandem electrochemical-thermochemical (EC-TC) strategy that overcomes these limitations. CO2 is first electrochemically reduced to a tunable mixture of C2H4 and CO, which is directly fed into a thermochemical reactor and converted into CNTs with controllable morphology and high CNT-to-metal mass ratios (~200) over NiFe catalysts at 750 °C. In situ synchrotron-based characterization and density functional theory calculations reveal that CO dissociation and C2H4 decomposition on NiFe alloys cooperatively promote CNT nucleation and sustained growth. This EC-TC strategy establishes a modular route for converting CO2 into value-added carbon nanomaterials.

Reaction-induced transformations in heterogenous catalysis represent diverse phenomena that challenge traditional views of static catalyst surfaces. From surface adsorbate dynamics, atomic rearrangements, to composition and phase transitions, these processes reveal the profound differences between idealized model systems under ultrahigh vacuum and the complex, evolving interfaces that govern real catalytic behaviors under reaction conditions. This perspective reviews recent theoretical efforts to provide atomic-level mechanistic insights into significant reaction-induced transformations and their impact on catalytic activity and selectivity. It underscores the need for an integrated framework that combines predictive simulations with operando characterization to uncover active sites and mechanisms under realistic operating conditions. Achieving this requires accelerating existing simulations to fully capture diverse reaction-induced surface dynamics, enabling scalable and accurate modeling of catalysts as condition-dependent, dynamically evolving systems. Such approaches are critical to bridge the gap between theory and practice, offering a pathway to more impactful and predictive catalyst design.

ABSTRACT Electrification of chemical production using renewable energy and abundant feedstocks offers a promising pathway for decarbonizing the chemical industry. Current efforts on CO 2 valorization largely focus on making chemicals and fuels. To help achieve net‐negative emissions through long‐term carbon storage, this study aims to develop efficient electrocatalysts for a tandem electrochemical‐thermochemical process to convert CO 2 into carbon nanofibers (CNFs). CO 2 and water are first electrochemically reduced in a membrane electrode assembly (MEA) electrolyzer to produce syngas (CO + H 2 ), which is subsequently fed into a thermochemical packed bed reactor to facilitate CNF growth. This work systematically evaluated Pd x Cu 1‐x bimetallic electrocatalysts to assess the effect of Pd–Cu alloying on enhancing syngas production while reducing Pd loading. Transmission electron microscopy and Raman spectroscopy confirmed the formation of high‐purity, crystalline CNFs, regardless of the syngas composition from the MEA. In situ X‐ray absorption spectroscopy and X‐ray diffraction measurements revealed that increasing Cu content in the Pd x Cu 1‐x alloy progressively inhibited palladium hydride formation, consistent with DFT calculations on the stability of Pd x Cu 1‐x under reducing electrochemical potentials.

The catalytic conversion of CO2 to formic acid (FA) represents a promising route for carbon utilization and sustainable chemical production. However, this process faces thermodynamic limitations and requires highly efficient catalysts. Conventional synthesis methods often lead to structural inhomogeneity and involve complex procedures, constraining their efficiency and scalability. To overcome these limitations, we developed a one-pot solvothermal approach combined with calcination to fabricate Ru/CeO2 catalysts. The as-synthesized catalysts feature atomically dispersed Ru species, a significantly increased concentration of oxygen vacancies on CeO2, and enhanced metal-support interactions, which work synergistically to promote reactant activation and catalytic performance. Under mild reaction conditions, the optimized Ru/CeO2 catalyst delivered high performance, achieving a turnover number (TON) of 1112 and a turnover frequency (TOF) of 139h-1. Moreover, the catalyst maintained high stability and recyclability over multiple reaction cycles, underscoring its potential for industrial implementation. This study offers an efficient and scalable synthesis strategy for designing high-performance heterogeneous catalysts, thereby advancing carbon emission mitigation and sustainable chemical synthesis.

Herein, we present a systematic comparison between Pd carbonyl (Pd-CO) species, specifically over Pd/CeO2 based catalysts, observed during isothermal adsorption and in several prototypical catalytic reactions to identify and understand CO adsorption on palladium-ceria based catalysts. Pd-CO is observed via DRIFTS to probe the gas-solid conditions, while ATR-IR is used to probe the affinity of Pd-CO under more complex solvated gas-solid-liquid conditions to discern the influence of the microenvironments for carbonyl adsorption. We explore the presence of Pd-CO under several reactive environments, including CO adsorption, CO2 + H2, CO + H2, CH4 + CO2 and CO under gas-solid-liquid media, highlighting reactions with notable Pd-CO formation. The differences between palladium carbonyls and carbonate species show that carbonyl species are much more affected via a shifting of the peak position than carbonates, which remain static irrespective of the immediate chemical environment. By following the rate of CO accumulation via K-M mode DRIFTS, we observe migration from linear, 2095 cm-1, to bridge site, 1978 cm-1, as a function of time under a static CO atmosphere. With the use of DFT, we discerned changes in Pd-carbonyl stretches due to both coverage effects of CO under simulated reaction conditions and temperature effects. Regardless of whether CO is formed as an intermediate or a reactant, the competitive adsorption of *H and *CO affects the binding strength of *CO at all temperatures, with low temperature favoring atop binding and high temperature favoring the more stable FCC Pd-CO site.