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Carbon‐based nanomaterials have been regarded as promising non‐noble metal catalysts for renewable energy conversion system (e.g., fuel cells and metal–air batteries). In general, graphitic skeleton and porous structure are both critical for the performances of carbon‐based catalysts. However, the pursuit of high surface area while maintaining high graphitization degree remains an arduous challenge because of the trade‐off relationship between these two key characteristics. Herein, a simple yet efficient approach is demonstrated to fabricate a class of 2D N‐doped graphitized porous carbon nanosheets (GPCNSs) featuring both high crystallinity and high specific surface area by utilizing amine aromatic organoalkoxysilane as an all‐in‐one precursor and FeCl3·6H2O as an active salt template. The highly porous structure of the as‐obtained GPCNSs is mainly attributed to the alkoxysilane‐derived SiOx nanodomains that function as micro/mesopore templates; meanwhile, the highly crystalline graphitic skeleton is synergistically contributed by the aromatic nucleus of the precursor and FeCl3·6H2O. The unusual integration of graphitic skeleton with porous structure endows GPCNSs with superior catalytic activity and long‐term stability when used as electrocatalysts for oxygen reduction reaction and Zn–air batteries. These findings will shed new light on the facile fabrication of highly porous carbon materials with desired graphitic structure for numerous applications. [ABSTRACT FROM AUTHOR]

3D porous carbon networks with highly dispersed SiOx have been successfully prepared by molecular-scale engineering with 1D molecular-brush precursors. Benefiting from the high-porosity interconnected structure and the lithiophilic SiOx nanodomains, the as-obtained composites show great advantages as 3D hosts to achieve stable Li plating/stripping. [ABSTRACT FROM AUTHOR]

As substitutes for perfluoroalkyl substances (PFASs), hexafluoropropylene oxide (HFPO) homologues are still environmentally problematic for their issues in toxicity, bioaccumulation, and long-distance mobility, which urges efficient removal technologies and in-depth mechanistic studies. Herein, we present the systematic optimizations on the electrochemical oxidation of 100 mg L−1 HFPO dimer acid (HFPO-DA) at a boron-doped diamond anode (3.6 V, 100 mM Na 2 SO 4 , pH 7.0), which exhibits a powerful mineralization capacity over 97% within 210 min of operation and is highly tolerant to various environmental factors. Under the optimized conditions, the structure-reactivity relationship has been analyzed by comparing six kinds of PFASs, proving that the increasing numbers of ether bonds in the HFPO homologues favor their removal and defluorination processes. Density functional theory (DFT) calculations further indicate that the facile, water-assisted cleavage of the ether bonds in the HFPO homologues can significantly reduce the energy barriers and shorten the "-CF 2 " unzipping degradation cycles, which is different from the conventionally proposed mechanism for degrading PFASs. Our findings demonstrate the promising application of electrochemical oxidation in the efficient removal of PFAS substitutes and offer new mechanistic insights for designing environment-friendly F-based chemicals. [Display omitted] Optimized electrochemical oxidation of HFPO-DA with a >97 % defluorination rate. The removal rates of all HFPO homologues all approach 100 %. DFT calculation shows the facile ether-bond cleavage promotes mineralization. [ABSTRACT FROM AUTHOR]

Piezo-potential promoted photocatalysis enables a scalable and high-efficiency dye decomposition by conjugating the photoexcitation and mechanical stimulus. However, its catalytic efficiency is significantly restricted by the limited quantum yield and piezoelectric activity of catalysts. Herein, a heterogeneous CdS-Au composite photocatalyst was synthesized via a facile water bath heating and reflux condensation method for organic pollutants degradation. The synergism between piezo-phototronic effect and localized surface plasmon resonance facilitates photon-generated carrier separation and internal quantum efficiency. The loading of Au nanoparticles remarkably modulates the morphologies, surface defect, effective optronics utilization and photocatalytic activities of CdS nanospheres. A 2.3 folds enhancement in the photodegradation of Methyl Orange (MO) was observed with the optimal 4 mol% Au loading. Furthermore, the impact of frequency and intensity of ultrasonication on the electrochemical impedance and photocatalytic activity was systematically investigated. This work offers a promising approach for harnessing noise or vibration for environmental remediation and opens up a new route for designing and developing high-performance piezo-photocatalyst. [Display omitted] • The synergism between surface plasma and piezo-phototronic effect was proposed. • A 2.3 folds enhancement in degradation was attained by loading 4 mol% Au NPs. • The impact of ultrasonic frequency and intensity on degradation was investigated. • Photogenerated carrier separation and internal quantum efficiency were improved. [ABSTRACT FROM AUTHOR]

• Inequality in urban greenspace provision is assessed for global large cities. • Marked disparities in urban greenspace exit among the high-income and low-income divisions. • Globally, compact cities suffer more urban greenspace issues, regardless of the financial capacity. • Climate plays a dominant role in shaping urban greenspace in most regions around the world. • Demographic and climatic factors have a nonlinear-enhanced effect on global urban greenspace. Given the important role of urban green space (UGS) playing in sustainable cities, UGS has received extensive attention and study. However, most studies were limited to individual cities or regions and yielded inconsistent results due to the use of diverse data sources and methods, and little is known about the inequality in green provision at the global scale. In this study, we compared green provisions and inequality in 1013 cities (built-up areas≥100 km2) around the globe utilizing the indicators of percentage of green area, green exposure, and Gini coefficient. Furthermore, their relation to demographic, geophysical and socioeconomic factors was estimated at the levels of the globe, geographical regions, and income divisions. We found that the large cities in high-income countries enjoy much more adequate and equitable UGS resources than that in low-income countries. In global context, population density is most strongly associated with UGS provision and inequality, while climate influence UGS to a higher extent than human activities in most regions. The interactions with demographic or climatic factors have a relatively significant nonlinear-enhanced effect on UGS. Our findings can provide insights for greening interventions at regional and global scales. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs), as a major source that significantly increase the risk of developing lung cancer, severely jeopardize public health in modern society. The analysis of PAHs and their metabolites (hydroxylated PAHs, OH-PAHs) is important for biomonitoring and exposure assessment. However, due to the difference in their physico-chemical properties and matrix interference, realizing high-performance extraction of both PAHs and OH-PAHs is still a challenge. Herein, a nickel-doped hierarchical porous carbon (Ni/HPC) is synthesized by carbonizing the polystyrene (PS) infiltrated metal-organic frameworks (MOF-74(Ni)). The obtained Ni/HPC exhibits hierarchical pores and evenly distributed Ni atoms, providing efficient diffusion pathways and adsorption sites. The custom Ni/HPC-coated solid-phase microextraction (SPME) fiber shows superior enrichment capabilities for PAHs and their metabolites under various interfering conditions, verifying its practicability in real sample analysis. The proposed method provides a new strategy to synthesize carbon-based adsorbents that achieves matrix-resistant enrichment of PAHs and OH-PAHs, which simplifies the related sample preparation process for environmental analysis and clinical diagnosis. [Display omitted] • A novel Ni-doping hierarchical porous carbon (Ni/HPC) is first synthesized. • Abundant micropores are formed by the carbonization of pore-confined polystyrene. • The Ni/HPC fiber shows structure-oriented and interference-free enrichment performance to PAHs and OH-PAHs. • The developed method is applied for precise quantifications of PAHs and OH-PAHs in human biofluids. [ABSTRACT FROM AUTHOR]

[Display omitted] • F/Cl-functionalized nanospheres are firstly synthesized as model adsorbents. • The relationship between microstructures and adsorption performance are summarized. • Exceptional enrichment effects of F- functionalized nanospheres are confirmed. • Highly sensitive analytical method is developed for quantifications of trace PCBs. Systematic investigation on the adsorption performance of polystyrene-based nanospheres towards persistent organic pollutants (POPs) is of great importance to the design of high-capacity adsorbent and the toxicological risk assessment of nano plastic. In this study, a series of polystyrene-based nanospheres with controllable microstructures, have been constructed successfully as model adsorbents, by the strategies of emulsion polymerization, hyper-crosslinking and direct carbonization. In the form of Solid phase microextraction (SPME) coatings, the impacts of microstructures on the adsorption performance of constructed nanospheres have been highlighted, by employing benzene series, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) as target adsorbates. Moreover, it is surprisingly found that the grafted F atoms make PS demonstrate better enrichment effects towards PCBs than the Cl atoms, mainly due to stronger sigma (σ)-hole interactions between F atoms and PCBs. In consideration of the most outstanding performance, the F-functionalized nanospheres (xFFNs)-coated SPME fiber is employed for the enrichment of PCBs from water samples, and the enrichment factors range from 1500 to 10030. After coupling the xFFNs-coated fiber with gas chromatography-mass spectrometry (GC-MS), highly sensitive analytical method is developed with detection limits of 0.08–0.89 ng L−1, realizing precise quantifications of trace PCBs in treated sewage samples. [ABSTRACT FROM AUTHOR]

• Landscape plants in China's major cities mainly originated from tropical and temperate regions. • The climatic niche breadths of domestic landscape plant species were wider than those of alien landscape plant species. • Arid cities with more acute environmental stresses included more species originated from mismatched climate zones. • The climatic sustainability of landscape plants responding to climate change varied by climate zones. Cities have become the main abodes for people, and landscape plants with their notable influence on quality of life, are important components of the urban ecosystem. The need to explore the climatic suitability and sustainability of landscape plants is especially relevant due to globalization and climate change. Nevertheless, this research area is constrained by the limited understanding of the biogeographical origin of landscape plants. We have compiled data on species lists, taxonomic information, and geographical and climatic origins for woody landscape plants in 36 major cities across China. We used climatic niche breadth (CNB) and climatic mismatched ratio (CMR) to assess the climatic suitability and sustainability of landscape plants. We found that 412 alien species had several hotspots of origin, mainly tropical regions in the Americas, Asia, and Australia. The 1258 domestic species mainly originated from temperate southern China. Tropical species had a conspicuous geographical clustering in coastal cities of southern China, while the temperate species were abundant in all cities. The CNBs of domestic species were wider than those of alien species, and arid cities with harsher environmental stresses (mainly due to the limited precipitation) registered higher CMRs. In terms of sustainability, the response of landscape plants to climate change varied across climate zones, being influenced by a rich presence of temperate species. Overall, our findings emphasized that landscape plant selections should not only pay attention to the existing landscape needs, but also consider the climatic sustainability of landscape plant species to climate change, especially for long lifespan woody plants. [ABSTRACT FROM AUTHOR]

Polymer adsorbents functionalized with amidoxime groups are widely considered to have the most industrial potential for uranium extraction from seawater. However, the entanglement upon the collapse of polymer chain in seawater greatly reduces the utilization ratio of amidoxime ligands. Herein, a novel star‐shaped molecular brush adsorbent (β‐CD‐g‐PAO) is obtained by densely grafting polyamidoxime (PAO) chains from β‐cyclodextrin (β‐CD). Experimental and theoretical results reveal that, in contrast to conventional linear polymer adsorbents, the star polymer adsorbent with a high grafting density of PAO side chains enables strong steric repulsion between the polymer chains, leading to increased persistence length and disentanglement of side chains. As a result, the star polymer adsorbent shows higher accessibility of the adsorption ligands with lower adsorption energy, achieving an adsorption capacity of up to 944.75 mg g−1 in uranium‐spiked seawater, surpassing that of conventional linear PAO by 3.2 times. Remarkably, this star polymer adsorbent demonstrates an extraordinarily adsorption capacity of 10.9 mg−1 g−1 in only 1 day in natural seawater, coupled with excellent affinity for uranyl ions (K = 0.31 pM). The unique topological structure design provides a new approach to solving the problem of low utilization ratio of functional ligands in polymer adsorbents. [ABSTRACT FROM AUTHOR]