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The interplay between bulk oxygen diffusion and surface reactions in reducible metal oxides is key in heterogeneous catalysts, yet direct measurements of their coupling through transient kinetics and in situ spectroscopies have been lacking. Here, the authors uncover complex H₂-driven dynamics in ceria–zirconia using transient mass spectrometry along with in-situ Raman, near-ambient pressure X-ray photoelectron spectroscopy, machine learning potential-based molecular simulations, and multiscale kinetic modeling.

Metal–metal oxide inverse catalysts are an intriguing class of materials, although the understanding of their structure–activity properties remains elusive. Here, Vlachos and colleagues unravel the complex dynamic interplay between Brønsted acid and redox sites at the surface of a PtWO_x/C inverse catalyst, offering a strategy to tune its acid-catalysed dehydration reactivity.

Core-shell catalysts display high activity but experimental characterization of active sites is challenging. Here, multiscale simulations of ammonia decomposition on various nickel-platinum catalysts show that the high activity can be attributed to dual nickel active sites with different catalytic roles.

Vibrational excitations are a fingerprint of molecule–surface interactions, but knowing how they scale across materials is tricky. Here, the authors discover correlations between the vibrational frequencies of adsorbates on transition metals, developing a predictive theory to allow interpretation of complex experimental spectra.

Chemical upcycling of polyolefin plastic waste over metal-based catalysts is crucial for the circular economy, but currently available methods are incompatible with chlorine-contaminated feedstocks. Here the authors propose a two-stage dechlorination–hydrogenolysis (or hydrocracking) upcycling strategy to tackle this problem.

Plastic additives can hinder the mechanical recycling of plastics; a similar issue arises in chemical deconstruction, where plastic additives can deactivate catalysts. Here the authors compare hydroconversion and catalytic pyrolysis to identify specific criteria needed to mitigate the effects organic additives on the deconstruction of polyolefins.

Upcycling end-of-life tire waste is complex due to the recalcitrant nature of the toxic legacy additive, 6PPD. Here the authors present a new decontamination strategy that can isolate 6PPD, convert it to safe and valuable products, and valorize end-of-life tire waste.

A critical component of plastics waste, polyvinyl chloride, is tough to recycle efficiently and sustainably owing to its high chlorine content. Now, research shows how to convert polyvinyl chloride mixed with polypropylene, at room temperature, into chlorine-free hydrocarbons.

This manuscript demonstrates a single-step electrified approach using rapid joule heating over an H-ZSM-5 catalyst for effective deconstruction of polyolefin plastic waste into light olefins (C2–C4) in milliseconds.

Solvents play a crucial role in catalysis, affecting both activity and selectivity. Here the authors demonstrate how solvent affinity to the catalyst surface influences the reaction pathways of 4-propylguaiacol.

Catalytic pathways of plastic waste valorization to lubricants are attractive avenues to foster circular economy. Tuning of catalyst electronic properties allows to significantly improve its activity due to boosted hydrogen storage on the surface.

Distinguishing the influence of oxygen functional groups in carbon materials is important but elusive. Here, the authors combine experimental and machine learning techniques and reveal that phenolic groups are more acidic than carboxylic groups.

Highly effective and selective noble metal-free catalysts continue to attract significant attention but require reaction specific tuning. Here, the authors fabricate a single-atom iron catalyst at low loading, which shows excellent transfer hydrogenation performance even at low reaction temperatures.

IR spectra are great for characterizing single-crystals and large nanoparticles, but not for highly dispersed heterogeneous catalysts made up of single-atoms and ultra-small clusters. To solve this, the authors developed a method to generate synthetic IR spectra using data-based approaches and physics-driven surrogate models.

Weak interactions between substrates and the active site environment have been known to be vital in enzyme catalysis. Inspired by this, the authors synthesize hyper-crosslinked porous polymer-based catalysts with different H-bonds to enhance adsorption and modify the interfacial sites and reactivity.

The discovery of heterogeneous catalysts for large molecule conversion has been lagging due to the combinatorial inventory of intermediates. Here, the author presents an automated framework to explore the chemical space of reaction intermediates.

Cheap and efficient hydrogen oxidation catalysts are needed for low cost hydroxide exchange membrane fuel cells. Here, the authors report that nickel nanoparticles supported on nitrogen doped carbon nanotubes have hydrogen oxidation activity similar to platinum-group-metals in alkaline electrolyte.

Understanding the catalysts’ structure evolution under working conditions is challenging. Here the authors use a multiscale simulation approach and machine learning to study the structures and nucleation of CeO₂-supported Pd clusters and single atoms at various catalyst loadings, temperatures, and exposures to CO.

By using a programmable electric current to allow rapid pulsed heating and quenching, a non-equilibrium, continuous synthesis technique shows improved performance in thermochemical reactions, as well as lower energy costs.

Metal oxides have been identified as a promising class of catalysts for carbon–oxygen bond cleavage in the context of biomass valorization, although the systematic understanding of their reactivity remains elusive. Now, a combination of catalytic screening and first principles calculations provide important insights into this family of catalysts.

Excess free charges on electrode surfaces drive changes in hydrogen electrocatalysis kinetics. Here, the authors show how redox solvent reorganization energy is insensitive to interfacial electric field strength; instead, the charged surface directly modulates proton electrochemical potential.

Knowing compositional motifs of nanoparticle catalysts in operando conditions is crucial towards understanding their catalytic behavior. Here, the authors develop a physics-driven machine learning approach to predict adsorption sites for a CO molecule over platinum nanoparticles in a multitude of coordination environments.

Supported subnanometre catalysts are atom efficient and possess unique properties, but their structure–activity relations are not well understood. Now it is possible to reveal their structure sensitivity by combining multimodal experiments and computations.

Reducible metal oxides selectively catalyse the hydrodeoxygenation of C–O bonds in bio-based aromatic molecules, although they show limited performance. Now, using TiO₂ as an example, a method is reported to enhance the activity of the oxide by surface doping with an ultralow loading of Pt.

The proton conductivity of polymer electrolyte membranes in fuel cells dictates their performance, but requires sufficient water management. Here, the authors report a simple method to produce well-dispersed transition metal carbide nanoparticles as additives to enhance the performance of Nafion membranes in fuel cells.

Catalysts consisting of oxide-supported pair sites can enable bifunctional reaction mechanisms with high activity and selectivity for reactions and so overcome the limitations in industry imposed by the use of homogeneous catalysts.

The decomposition of ammonia is an important process if ammonia is to be used as a hydrogen storage medium. The most active catalyst for this is ruthenium, but its expense has provoked the search for alternatives. Now, using theory to guide the investigation, researchers have identified a bimetallic nickel–platinum surface as an active catalyst for this process.

Theoretical electronic-structure methods are routinely used to estimate the parameters of complex kinetic models. It is now shown that uncertainty in such model parameters is correlated and that it can be quantified. An associated sensitivity analysis method is also derived that handles complex systems with many correlated reactions.

Liquid phase reactions mediated by solid catalysts occur in the presence of solvents whose role needs to be understood. The authors use attenuated total reflection infrared spectroscopy to measure liquid-phase pyridine adsorption isotherms in zeolites, elucidating the effect of coadsorbed solvents on the interactions.

Advanced recycling is an end-of-life option for plastics waste toward the generation of high-value products. This Review highlights the importance of developing holistic analyses of candidate recycling technologies, with a focus on industrial pitfalls, key assessment parameters, complexities of recycling infrastructure, scale-up considerations, and environmental and economic trade-offs.

To achieve net-zero carbon emissions, we must close the carbon cycle for industries that are difficult to electrify. Developing the needed science to provide carbon alternatives and non-fossil carbon will accelerate advances towards defossilization.

Biomass is a renewable source of carbon that can be exploited to produce valuable chemicals and fuels. This Perspective discusses the electrochemical valorization of biomass, identifying specific chemical transformations in which the approach can excel.

A rapid screening approach is developed to access the stability of single-atom catalysts based on the binding energy of the metal atom to the support and the cohesive energy of the bulk metal.