Electrocatalytic hydrazine oxidation holds great promise for enabling fuel cell-powered transportation since hydrazine hydrate (N₂H₄·H₂O) has the highest energy density of all liquid, CO₂-free fuels (3.45 kWh/L), and the highest fuel cell voltage (1.56 V vs O₂). Inspired by the ruffling of catalytic centers in oxidative enzymes, we designed a twisted single-atom nanozyme comprising twisted FeN₂₊₂C₄₊₄ sites, enabling high accessibility of N₂H₄ and OH^– reactants. Experimental evidence shows that this nanozyme catalyst achieves the lowest oxidation overpotential of all Fe–N–C materials, both in the lab and in direct hydrazine fuel cells, with an open-circuit voltage of 0.95 V, unprecedented for an Fe-based anode. The structure of the catalytic site is elucidated through a combination of electrochemistry, ⁵⁷Fe Mössbauer spectroscopy, high-resolution transmission electron microscopy, and X-ray absorption spectroscopy with crystal field multiplet simulations and fits of the pre-edge features, as well as density functional theory calculations and theoretical simulations of X-ray absorption near edge structure. The experimental and theoretical methods reveal that twisting the active site also shifts its oxidation potential positively and improves N₂ bubble removal while limiting ammonia production to less than 10 ppm. This work demonstrates the potential of active site twisting to enhance the oxidation of energy-rich and liquid substrates, representing a crucial step toward building a sustainable society.

To realize the full potential of waste-derived electrodes, their synthesis must be fully reproducible and their environmental life cycle impact must be assessed quantitatively. We now show how a systematic comparison of coffee wastes as sources for direct hydrazine fuel cell anodes can inform the first full life cycle assessment (LCA) of this application. The result is a practical process yielding active and replicable materials, whose quantified environmental footprint points to actionable avenues for further development.

Electrochemical CO₂ reduction catalysis with cobalt corrole complexes in solution is reported. Corroles have attracted attention as contracted and trianionic tetrapyrrolic macrocycles that can be compared to leading porphyrin catalysts for CO₂ reduction, but most studies focus on heterogenized systems with poorly defined electrochemical responses. Electrochemical studies of cobalt corroles bearing axial triphenylphosphine ligands to ensure solubility are reported. The voltammetry provides mechanistic insights supporting CO₂ activation after the formal Co^II/Co^I reduction. The series of cobalt complexes, including a newly designed corrole with mixed perfluorophenyl/ortho-dimethoxyphenyl substituent pattern, provide evidence for electron-rich catalysts having stronger interactions with CO₂. The primary product of CO₂ reduction is CO, formed at a rate of ca. 90 s⁻¹.

Earlier measurements of the velocity correlated cluster emission (VCCE) effect in keV C₆₀⁻ impact with a silver target (Ag_n⁺ (n = 1–9), E. Armon, A. Bekkerman, Y. Cohen, J. Bernstein, B. Tsipinyuk, E. Kolodney, Phys. Rev. Lett., 2014, 113, 027604) are extended to much larger clusters up to Ag₂₁⁺. This is the largest range of cluster size demonstrated so far for the impact induced emission of velocity correlated clusters from any target. Measurements of the kinetic energy distributions (KEDs) of all emitted Ag_n⁺ (n = 1–21) cluster ions showed that the VCCE effect as exhibited by a linear increase of most probable energies of the KEDs as a function of cluster size, E_mp(n) is still valid up to Ag₂₁⁺. The extension of the cluster size range was achieved mainly by applying a higher extraction/acceleration voltage for the surface emitted cluster ions than done before for the smaller range (U_ext. = 100 V as compared with 25 V before). The preferential collection and detection of some off-normal lower energy cluster ions resulted in a rather moderate and nearly constant 1–2 eV decrease of E_mp(n) as compared with the earlier (U_ext. = 25 V) results. Namely, the slope of the linear E_mp(n) relation (representing the strength of the VCCE effect) is nearly unaffected by the extraction voltages. It shows that the distortion of the VCCE effect by the extraction field is rather small and specifically, that the effect is getting more pronounced with decrease of the extraction voltage. The observation reported here is important for extending the range of validity of the VCCE effect and for gaining a deeper understanding of the nature and size of the (hypothesized) superhot moving precursor serving as the source for all the emitted clusters.

Replacing common polymeric binder materials in lithium-ion batteries (LIBs) with more sustainable and environmentally friendly options is one of the challenges in designing new generations of LIBs. Here, we explain how incorporating protein-based polymers into the binder formulation can enhance binder performance in the graphite anode of LIBs. The electrode preparation with these binders involves an atypical thermal treatment (“baking”) that causes structural transformation. The effect of baking temperature on battery performance is examined using various methods covering morphological, structural, and electrochemical aspects. We find that baking the binders at temperatures above 120 °C removes tightly bound water molecules, which impair LIB performance. Water removal promotes intra- and inter-molecular bond formation among the binder components, while the primary covalent structure of these binders remains unchanged. Ultimately, using thermally treated binders enhances the electrochemical performance of graphite anodes and provides strong adhesion. The ideas presented here could significantly influence the design of new binders for LIBs.

We report the first example of a cationic tripodal ligand consisting of a sulfonium donor embedded within a tripodal scaffold. Coordination of this ligand to Rh(I) gives rise to a series of mono- and bis-cationic Rh(I) complexes, all featuring a trigonal bipyramidal geometry. To elucidate the distinctive characteristics of the new sulfonium ligand, its Rh(I) carbonyl complex was subjected to a comprehensive structural (XRD) and spectroscopic (NMR, IR) analysis, in direct comparison with isostructural analogs featuring neutral P-based and anionic Si-based ligands. This study revealed systematic trends along this series, including a progressive shortening of the central E-Rh bond (E = Si, P, S) and an increasing blue shift of the CO stretching frequencies. These results were fully corroborated by density functional theory calculations, which also indicated a steady depletion of the local negative natural charge on the Rh atom along the series. Electrochemical studies (CV) further highlighted the profound effect imposed by the cationic sulfonium donor on the coordinated Rh(I) center, revealing an anodic shift of ~1.0 V in its reduction potential, relative to the P-based analog. The Lewis acidity of coordinatively unsaturated Rh(I) complexes was quantified using the Guttman-Becket method, yielding acceptor numbers approaching those of the highly Lewis acidic polyfluoroaryl boranes for the sulfonium complex. Finally, we demonstrated that the enhanced Lewis acidity of the Rh(I) center imparted by coordination to the sulfonium donor can be exploited in Lewis acid catalysis, as illustrated by a series of representative 2:1 double condensations of ketones with indole or pyrrole.

The hydrogenation of carbon dioxide (CO2) to methanol (CH3OH) using green hydrogen is a key pathway in sustainable energy conversion. However, conventional thermocatalytic routes are fundamentally constrained by thermodynamic and kinetic barriers, especially under ambient conditions. Here, we report a one-pot synthesized, non-noble In2O3–CeO2 heterojunction catalyst that achieves benchmark CO2-to-CH3OH conversion rates under visible-light irradiation at ambient pressure. At 247.7 °C, the optimized catalyst (In3+:Ce3+ = 1:1) delivers a CH3OH production rate of 1054.6 μmol g-1 h-1 with 53.1% selectivity - exceeding, to the best of our knowledge, all previously reported non-noble photothermal systems operating under comparable conditions. Supported by both theory (DFT) and operando spectroscopy (e.g., DRIFTS), the mechanistic origins of the observed activity are attributed to a synergistic interplay among oxygen vacancies, surface hydroxyls, and Ce3+/Ce4+ redox cycles, which collectively enhance CO2 activation and promote selectivity. In addition, we identify a distinct pathway wherein photogenerated charge carriers directly contribute to the catalytic cycle, beyond purely thermal effects. This work outlines a mechanistically guided strategy for designing efficient, scalable, and non-noble photothermal catalysts for solar-assisted CO2 valorization.

Periodic driving is used to steer physical systems to unique stationary states or nonequilibrium steady states (NESS), producing enhanced properties inaccessible to non-driven systems. For open quantum systems, characterizing the NESS is challenging and existing results are generally limited to specific types of driving and the Born-Markov approximation. Here we go beyond these limits by studying a generic periodically driven $ N$-level quantum system interacting with a low-density thermal gas. Exploiting the framework of Floquet scattering theory, we establish general Floquet thermalization conditions constraining the nature of the NESS and the transition rates. Moreover, we examine theoretically the structure of the NESS at high temperatures, and find out that the NESS complies, rather surprisingly, with the Boltzmann law for any driving. Numerical calculations illustrate our theoretical elaborations for a simple toy model.

This study investigates the influence of crystal orientation on nitrogen incorporation, bonding configurations, and thermal stability in (100)- and (111)-oriented single-crystal diamond (SCD) surfaces implanted with ultra-low-energy N₂⁺ ions (100 and 200 eV; dose: 1 × 10¹⁵ ions/cm²). Upon impact, N₂⁺ ions dissociate, and each interacting nitrogen atom receives half the kinetic energy (50 and 100 eV), making the process ideal for studying near-threshold defect formation. Low-energy electron diffraction revealed a reconstructed surface with coexisting (2 × 1) and (1 × 2) domains on (100) SCD, while the (111) surface maintained a well-ordered (1 × 1) structure. X-ray photoelectron spectroscopy showed that (100) SCD incorporates and retains more nitrogen than (111), with superior thermal stability up to 1000 °C. Despite the low implantation energy, both surfaces exhibit minimal structural defect (C_def), although (100) SCD is slightly more susceptible to defect formation. Implanted nitrogen forms primarily C–N/C $\text{=}$ N and N–(sp² C/C_def) bonds, with the former dominating. These bonding configurations evolve with temperature and crystal orientation. The N–(sp² C/C_def) component remains stable between 300 and 700 °C and decreases at higher temperatures. At lower temperatures, nitrogen remains in interstitial form (N_i), forming N_i–C_i complexes with mobile carbon interstitials (C_i), which stabilize N–(sp² C/C_def) bonding. At elevated temperatures (800–1000 °C), N_i converts to substitutional nitrogen (N_s), reducing the defect-associated bonding signal. Overall, (100) SCD shows a stronger tendency for defect-mediated nitrogen stabilization than (111). These insights into ultra-low-energy nitrogen–diamond interactions may guide future strategies for surface engineering and stabilization of shallow nitrogen-vacancy centers in diamond-based quantum technologies.

Laser-induced phase transitions offer pathways of phase transitions that are inaccessible by conventional stimuli. In this study, we conduct ab initio simulations to numerically demonstrate a novel laser-induced structural transformation: converting a bulk crystal into a layered van der Waals material using intense light pulses. The transition is driven by a nonlinear phononic mechanism, where selectively exciting polar and anti-polar phonon modes with polarized terahertz light breaks targeted interlayer bonds while preserving intralayer ones. We identify that strong anisotropy in bond sensitivity where interlayer bonds are significantly more susceptible to excitation than intralayer bonds is the critical prerequisite. Our findings pave the way for on demand transformations from bulk to 2D materials, facilitate the design of advanced phase-change devices, and suggest a potential optical exfoliation method to expand the range of exfoliable 2D materials.