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Soil contamination by metals and metalloids (metal[loid]s) is a global issue with significant risks to human health, ecosystems, and food security. Accurate risk assessment depends on understanding metal(loid) mobility, which dictates bioavailability and environmental impact. Here we show a theory-guided machine learning model that predicts soil metal(loid) fractionation across the globe. Our model identifies total metal(loid) content and soil organic carbon as primary drivers of metal(loid) mobility. We find that 37% of the world’s land is at medium-to-high mobilization risk, with hotspots in Russia, Chile, Canada, and Namibia. Our analysis indicates that global efforts to enhance soil carbon sequestration may inadvertently increase metal(loid) mobility. Furthermore, in Europe, the divergence between spatial distributions of total and mobile metal(loid)s is uncovered. These findings offer crucial insights into global distributions and drivers of soil metal(loid) mobility, providing a robust tool for prioritizing metal(loid) mobility testing, raising awareness, and informing sustainable soil management practices. Evaluating soil metal(loid) mobility at large scales is nearly intractable by laboratory experiments. This study uses theory-guided machine learning methods to map the global distribution of soil metal(loid) mobility and analyzes its primary drivers.

Excessive levels of heavy metal(loid)s (HMs) in natural environments pose a serious threat to living beings worldwide. HM exposure causes irreversible damage to structural components and metabolic processes in living organisms, as has been observed in multiple studies on various organisms. In the natural environment, biological individuals interact with others through the food web rather than exist independently, which facilitates the transfer of HMs in the food web. However, the difference in HM toxicity among different biological species has not been elucidated. This review provides information on the speciation and migration of HMs in different environments to clarify the HM exposure routes of different biological species. The differences in the biotoxicity of HMs to different species, from microbes to humans, are emphasized. The relationship between HM toxicity and biological species is confirmed by the fact that HMs can be transferred and bioaccumulated along the food chain. Effective strategies for decreasing HMs emissions and removing HMs from the environment are briefly discussed. Finally, the limitations of the present study and future perspectives are discussed.

Single-atom catalysts (SACs) have received increasing attention due to their 100% atomic utilization efficiency. The electrochemical CO 2 reduction reaction (CO 2 RR) to CO using SAC offers a promising approach for CO 2 utilization, but achieving facile CO 2 adsorption and CO desorption remains challenging for traditional SACs. Instead of singling out specific atoms, we propose a strategy utilizing atoms from the entire lanthanide (Ln) group to facilitate the CO 2 RR. Density functional theory calculations, operando spectroscopy, and X-ray absorption spectroscopy elucidate the bridging adsorption mechanism for a representative erbium (Er) single-atom catalyst. As a result, we realize a series of Ln SACs spanning 14 elements that exhibit CO Faradaic efficiencies exceeding 90%. The Er catalyst achieves a high turnover frequency of ~130,000 h − 1 at 500 mA cm − 2 . Moreover, 34.7% full-cell energy efficiency and 70.4% single-pass CO 2 conversion efficiency are obtained at 200 mA cm − 2 with acidic electrolyte. This catalytic platform leverages the collective potential of the lanthanide group, introducing new possibilities for efficient CO 2 -to-CO conversion and beyond through the exploration of unique bonding motifs in single-atom catalysts. Single atom catalysts offer a promising approach for CO 2 electroreduction to CO, but achieving high efficiency remains challenging. Here, the authors report lanthanide single atom catalysts with the transition ability from bridge to linear adsorption that exhibit efficient CO production.

Acidic CO 2 electroreduction to multi-carbon (C 2+ ) products using Cu-based catalyst has attracted considerable attention for CO 2 recycling due to high single-pass CO 2 utilization. However, its development is drastically limited by the poor stability, especially at high current density, caused by Cu dissolution/reconstruction during the reaction. Herein, we find the trace dissolved oxygen in the electrolyte accounts for the Cu dissolution/reconstruction and report an in-situ passivation strategy to prevent oxygen adsorption for inhibiting Cu dissolution/reconstruction for high stability CO 2 -to-C 2+ conversion. Theoretical and in situ spectroscopy demonstrate that aluminum citrate (AC) passivation layer decreases the adsorption of oxygen on Cu surface to effectively prevent the Cu oxidation, which is beneficial for the formation and adsorption of linearly bonded *CO toward C-C coupling. As the result, the Cu catalysts with AC layer achieve over 60% Faradaic efficiency C 2 H 4 and 38.7% energy efficiency to C 2+ for over 150 h stability at 500 mA cm −2 in strong acidic electrolyte. The use of Cu catalysts for the CO 2 reduction reaction is hindered by their poor stability. The authors find that traces dissolved oxygen in the electrolyte results in Cu dissolution/reconstruction and report an in-situ passivation strategy to prevent oxygen adsorption in high stability.

Doc number: 1 Abstract Background: Lignin materials are abundant and among the most important potential sources for biofuel production. Development of an efficient lignin degradation process has considerable potential for the production of a variety of chemicals, including bioethanol. However, lignin degradation using current methods is inefficient. Given their immense environmental adaptability and biochemical versatility, bacterial could be used as a valuable tool for the rapid degradation of lignin. Kraft lignin (KL) is a polymer by-product of the pulp and paper industry resulting from alkaline sulfide treatment of lignocellulose, and it has been widely used for lignin-related studies. Results: Beta-proteobacterium Cupriavidus basilensis B-8 isolated from erosive bamboo slips displayed substantial KL degradation capability. With initial concentrations of 0.5-6 g L-1 , at least 31.3% KL could be degraded in 7 days. The maximum degradation rate was 44.4% at the initial concentration of 2 g L-1 . The optimum pH and temperature for KL degradation were 7.0 and 30°C, respectively. Manganese peroxidase (MnP) and laccase (Lac) demonstrated their greatest level of activity, 1685.3 U L-1 and 815.6 U L-1 , at the third and fourth days, respectively. Many small molecule intermediates were formed during the process of KL degradation, as determined using GC-MS analysis. In order to perform metabolic reconstruction of lignin degradation in this bacterium, a draft genome sequence for C. basilensis B-8 was generated. Genomic analysis focused on the catabolic potential of this bacterium against several lignin-derived compounds. These analyses together with sequence comparisons predicted the existence of three major metabolic pathways: β -ketoadipate, phenol degradation, and gentisate pathways. Conclusion: These results confirmed the capability of C. basilensis B-8 to promote KL degradation. Whole genomic sequencing and systematic analysis of the C. basilensis B-8 genome identified degradation steps and intermediates from this bacterial-mediated KL degradation method. Our findings provide a theoretical basis for research into the mechanisms of lignin degradation as well as a practical basis for biofuel production using lignin materials.

Electrosynthesis of NH 3 from low-concentration NO (NORR) in neutral media offers a sustainable nitrogen fixation strategy but is hindered by weak NO adsorption, slow water dissociation, and sluggish hydrogenation kinetics. Herein, we propose an intriguing strategy that successfully overcomes these limitations through using an electron-donating motif to modulate NO-affinitive catalysts, thereby creating dual active site with synergistic functionality. Specifically, we integrate electron-donating nanoparticles into a Fe single-atom catalyst (Fe SAC ), where Fe sites ensure strong NO adsorption, while electron-donating motifs promote water dissociation and NO hydrogenation. In situ X-ray absorption spectroscopy (XAS), in situ attenuated total reflection-infrared spectroscopy (ATR-IR), and theoretical calculations reveal that electron-donating motifs increase Fe site electron density, strengthening NO adsorption. Additionally, these motifs also promote water dissociation, supplying protons to lower the NO hydrogenation barrier. This synergistic interplay enables a cascade reaction mechanism, delivering a remarkable Faradaic efficiency (FE) of 90.3% and a NH 3 yield rate of 709.7 µg h −1 mg cat. −1 under 1.0 vol% NO in neutral media, outperforming pure Fe SAC (NH 3 yield rate: 444.2 µg h −1 mg cat. −1 , FE: 56.6%) and prior to systems operating under high NO concentrations. Notably, the high NH 3 yield of 3207.7 μg h −1 mg cat. −1 is achieved in a membrane electrode assembly (MEA) electrolyzer under a 1.0 vol% NO. This work establishes an inspirational paradigm in NORR by simultaneously enhancing NO adsorption, water dissociation, and hydrogenation kinetics, providing a scalable route for efficient NH 3 electrosynthesis from dilute NO sources. Weak NO adsorption, slow water dissociation, and sluggish hydrogenation hinder neutral-media NH 3 electrosynthesis from low-concentration NO. Here, the authors report an electron-donating motif modulating a NO-affinitive catalyst to create dual active sites, thus facilitating NO-to-NH 3 conversion.

Highly conductive electrolytes and stable electrolyte|electrode interfaces are desired for next-generation batteries. Constructing solid-electrolyte interphases on electrodes is a prevailing strategy for enhancing interfacial stability but fails to prevent inevitable breakdown and reformation of interphases during prolonged cycling. Herein, a decoupled electrolyte is designed by introducing a co-solvent (tetraethylene glycol dimethyl ether) with high stability and high positive electrostatic potential values into highly conductive dimethylformamide-based electrolytes, which suffer from electrolyte|positive electrode instability. The preferential adsorption of cations solvated with co-solvents on the positive electrode during discharge induces the formation of a co-solvent-rich localized environment, inhibiting side reactions and contributing to long cyclability. Meanwhile, dimethylformamide in the bulk electrolyte helps to maintain high ionic conductivity, thus improving kinetics. Notably, lithium-carbon dioxide cells with this decoupled electrolyte demonstrate a significantly improved cycle life of ~ 2600 hours and a low overpotential of ~ 1 V, even with a metal-free commercial reduced graphene oxide catalyst. Our work provides an alternative strategy to solid-electrolyte interphase construction for stabilizing electrolyte|electrode interface and unlocks the potential of previously underexplored solvents in batteries. Electrolyte|electrode instability largely limits battery lifespan of lithium-carbon dioxide batteries. Here, authors design a decoupled electrolyte system that enables long-term cycling and low overpotential in Li-CO 2 batteries by regulating solvation structures near the positive electrode during dynamic cycling.

Catalytic hydrolysis is an effective strategy for decomposing tetrafluoromethane (CF 4 ), one of the most chemically inert per- and polyfluoroalkyl substances (PFAS). A key challenge in this process lies in enhancing proton availability to facilitate efficient and stable C–F bond activation while ensuring long-term catalyst stability. Here we present an SO 2 -driven approach to significantly enhance H 2 O dissociation and proton-supplying through the in situ formation of Al–HSO 4 and Ga–HS species. Combined experimental and theoretical investigations reveal that these species not only lower the energy barrier for C–F bond activation but also promote active site regeneration by facilitating defluorination, thus effectively overcoming catalyst deactivation. As a result, the optimized catalyst enables complete CF 4 decomposition at a low temperature of 550°C, with stable operation for over 2500 hours. This work establishes a new paradigm for regulating proton transfer and offers a viable route for the efficient, durable degradation of gaseous PFAS. Catalytic breakdown of highly persistent fluorinated pollutants is hindered by limited proton availability and catalyst degradation. This study shows that in situ proton-supplying sites enable low-temperature, long-lasting decomposition of stubborn PFAS gas.

Electroreduction of nitrate (NO 3 ‒ ) to ammonia (NH 3 ) is a promising approach for addressing energy challenges. However, the activity is limited by NO 3 ‒ mass transfer, particularly at reduction potential, where an abundance of electrons on the cathode surface repels NO 3 ‒ from the inner Helmholtz plane (IHP). This constraint becomes pronounced as NO 3 ‒ concentration decreases, impeding practical applications in the conversion of NO 3 ‒ -to-NH 3 . Herein, we propose a generic strategy of catalyst bandstructure engineering for the enrichment of negatively charged ions through solid-liquid (S-L) junction-mediated charge rearrangement within IHP. Specifically, during NO 3 ‒ reduction, the formation of S-L junction induces hole transfer from Ag-doped MoS 2 (Ag-MoS 2 ) to electrode/electrolyte interface, triggering abundant positive charges on the IHP to attract NO 3 ‒ . Thus, Ag-MoS 2 exhibits a ~ 28.6-fold NO 3 ‒ concentration in the IHP than the counterpart without junction, and achieves near-100% NH 3 Faradaic efficiency with an NH 3 yield rate of ~20 mg h ‒1 cm ‒2 under ultralow NO 3 ‒ concentrations. Electroreduction of low-concentration NO 3 − to NH 3 is limited by NO 3 − mass transfer. Here, the authors propose a strategy for NO 3 − enrichment through charge rearrangement within the inner Helmholtz plane, achieving near-unity conversion of NO 3 − to NH 3 .

According to the International Energy Agency (IEA), by 2050, ore-based lithium extraction could emit around 60 million tons of CO2 annually, comparable to the electricity consumption of approximately 39 million households [6]. Combined scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDS) and electron probe microanalysis (EPMA) offer morphological and compositional insights but fall short in detecting trace-level species or elucidating crystal structure. Many such phases exhibit polytypism, disorder, or twinning, escaping detection by conventional powder XRD. 3D-ED provides single-crystal data of structure solution and refinement quality, which enables structure solution and refinement from crystallites smaller than 100 nm, providing definitive atomic-scale information [12]. Combining principal-components mapping (SEM-EDS or EPMA) with trace-element techniques such as laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) or time-of-flight secondary ion mass spectrometry (TOF-SIMS) enables co-localization of Be and Tl with specific mineral domains.