Green Chemistry最新文献

Single-atom catalysts towards the oxygen reduction reaction (ORR) often suffer from unsatisfactory activity and poor stability. Herein, for the first time, we successfully modulated the electronic structure of the Mn–N–C catalyst by introducing chalcogen oxygen groups (XO₂, X = S, Se, Te), which induce changes in the Mn–N bond length in the MnN₄ structure, thereby modulating the electronic structure of the metal center Mn. The experimental results demonstrate that the introduction of XO₂ groups results in the rearrangement of Mn 3d electrons, which can be strongly correlated with the ORR activity of the Mn–N–C catalysts, among which the SeO₂ modification increases the kinetic current density of the Mn–N–C catalyst achieving a half-wave potential (E_1/2) of 0.79 V versus the reversible hydrogen electrode, approaching that of Fe–N–C catalysts along with significant stability in acidic media. The promising performance of the Mn–N–C catalyst as a PGM-free cathode was confirmed through fuel cell testing. First-principles calculations demonstrate that the introduced XO₂ group downshifts the d-band center of the Mn center, thus successfully optimizing the adsorption of oxygen intermediates. This finding significantly facilitates the activity enhancement of Mn–N–C catalysts via the construction of a geometric structure–electronic structure–catalytic property relationship.

Heterogenized molecular electrocatalysts hold great promise for the electrocatalytic conversion of CO₂ into higher-value products. However, their practical application is hindered by the aggregation due to π–π interactions and the instability from cobalt site leaching. Using cobalt phthalocyanine (CoPc) as a model system, we present a simple hyper-crosslinking strategy to fabricate a three-dimensional porous organometallic polymer (CoPc POP) with enhanced activity and stability. This approach preserves the excellent catalytic performance of CoPc while ensuring uniform dispersion of active sites within the porous channels. The maximized exposure of Co sites improves electron and substrate interactions, leading to significantly enhanced CO₂ reduction reaction (CO₂RR) performance. Even in an electrolyte with a pH of 1, the optimized CoPc POP catalyst achieves an impressive CO Faradaic Efficiency (FE_CO) of 91.2% at a high current density of 850 mA cm⁻², with a turnover frequency (TOF) of 3.10 × 10⁴ h⁻¹. Notably, the robust polymer framework effectively mitigates cobalt site leaching, maintaining an FE_CO above 95.7% during a 14 hour stability test.

The environmental impact of non-degradable single-use plastics poses a significant challenge to current sustainability efforts. To foster a sustainable circular economy, this study introduces grass biomass as a renewable resource for the production of innovative bioplastics. The research involves the direct conversion of grass waste into composite bioplastics through alkaline hydrolysis, offering a transformative approach to plastic manufacturing. The hydrolysis process was optimized by varying treatment times and alkaline concentrations, with the ideal conditions identified as 1 M NH₃ and 24 hours of treatment. Subsequently, the incorporation of ε-polylysine (PL) enhanced the mechanical properties of the bioplastics by acting as a plasticizer. Mechanical testing revealed that samples containing 10% and 20% PL exhibited comparable rigidity, with a Young's modulus of approximately 700 MPa and a tensile strength of 10 MPa. Moreover, the addition of PL, up to 20%, significantly improved the water resistance of the bioplastics, evidenced by decreased moisture content and water solubility. Additionally, the bioplastics demonstrated effective antimicrobial activity against Escherichia coli and Staphylococcus aureus, as well as significant antioxidant activity. Life cycle assessment (LCA) and life cycle costing (LCAA) results demonstrate the potential environmental benefits of manufacturing grass biomass into plastic films, with a significant reduction in greenhouse gases, cumulative energy demand (CED), and cost when compared to benchmark packaging plastics. These promising properties indicate that these biomaterials could be effectively utilized in real-world applications, with potential application as sustainable biobased packaging materials.

Correction for ‘Iron-photocatalyzed desulfurizing chlorination with seawater’ by Boning Gu et al., Green Chem., 2025, https://doi.org/10.1039/D4GC06456A.

Reductive transformation of CO₂ using green hydrogen or methanol enables the production of industrially significant chemicals such as carboxylic acid esters, which, however, is hindered by the dependence on noble metal catalysts and the use of halide additives. Here we report a robust non-noble metal-based, halide-free catalytic system for the reductive methoxycarbonylation of ethylene with CO₂/MeOH. This system achieves a turnover number of up to 110 for methyl propionate, a key precursor in polymethyl methacrylate production, showing a better performance than conventional noble-metal-based systems. Remarkably, the present system exhibits moderate performance under simulated flue gas containing NO_x and SO_x, demonstrating the potential for in situ CO₂ capture and conversion into value-added chemicals, promoting green and sustainable development.The success of the strategy lies in the unprecedented in situ formation and alcoholytic ring-opening of a five-membered nickelalactone, effectively bypassing the conventional but challenging CO₂-to-CO-carbonylation pathway. Notably, this protocol offers a process free from noble metals, halide/acid additives, and strong/expensive reductants, for the production of next-generation CO₂-based polymers.

The efficiency of photocatalytic ammonia production is limited by insufficient active sites and sluggish interfacial charge transfer in photocatalysts. To address this, a titano-oxide phthalocyanine monatomic layer (TiOPc) is modified onto the face-centered cubic structured CdIn₂S₄via a hydrothermal process, significantly increasing the number of active sites. The close proximity of CdIn₂S₄ and TiOPc creates a local interface with an asymmetric configuration, resulting in a pronounced potential difference and an electron-rich TiS₁O₁N₂ polarization site. This configuration facilitates rapid charge transport between the two materials through the interfacial Ti–S bond. Profiting from these properties, TiOPc/CdIn₂S₄ delivers an impressive NH₃ formation rate of 2572.8 μmol g⁻¹ h⁻¹ and an apparent quantum efficiency achieving 7.16%, 6.86%, 4.12%, 2.13%, 1.86% and 1.15% at 400, 450, 500, 550, 650 and 700 nm, respectively. This study offers a practical method for designing symmetry breaking structures and establishing strongly coupled interfaces to enhance photocatalytic performance.

Green synthesis involving visible-light EDA chemistry, multi-component systems and water as a medium is highly attractive and desirable in academia and industry. Herein, we offer a protocol to achieve a photocatalyst- and additive-free multi-component reaction driven by a cyclopropylamine-based EDA complex in water. A mechanistic study revealed that electron-deficient alkenes served as electron acceptors, enabling the formation of an EDA complex with cyclopropylamine. A series of cyclopentylamines derived from readily available cyclopropylamine, aldehyde and activated methylene species can be provided in moderate to excellent yields (up to 93%). The applicability of this method has been further demonstrated in the late-stage functionalization of a number of commercially available pharmaceutical compounds and exploration of their derivatization.

Growing interest in sustainable and efficient metal ion separation has led to the exploration of non-ionic deep eutectic solvents (DESs), also known as type V DESs, as promising alternatives to conventional organic phases in solvent extraction (SX). This work summarizes recent developments, focusing solely on the use of non-ionic DESs and excluding ionic DESs, for the separation of metal ions from synthetic and real leachates. The review does not aim to exhaustively cover all studies but focuses on the molecular mechanisms of SX, how inherent properties of DESs influence these mechanisms, and how they can be harnessed to improve the separation selectivity. It further highlights the physico-chemical properties of DESs in SX and compares them with traditional systems, emphasizing similarities and new opportunities. The overall aim is to clarify the potential and limitations of type V DESs in SX, including their often touted credentials as “green solvents”, and to offer guidelines for their practical use and addressing skepticism towards novel solvents in hydrometallurgy.

The deuteromethyl group is an ideal bioisostere to replace “magic methyl” due to its profound pharmacological effects and physical properties in medicinal chemistry and chemical biology. Despite the remarkable advances in the construction of CD₃ units, a compelling challenge that remains to be solved is the deuterium labeling of bioactive and functional molecules to introduce methyl-d₃ groups with high efficiency. Among them, the introduction of Se-methyl-d₃, a promising and vital block and a dual bioisostere for the replacement of the methoxyl or S-methyl entity, is limited to the concise and general process. Herein, we have designed and developed a novel and highly efficient access to the formation of two types of deuterated methylselenylating reagent libraries bearing electrophilicity, nucleophilicity, and radical properties. These reagents can be facilely utilized to achieve late-stage modification of functional molecules and even to construct SeCD₃ substituted pharmaceutical analogues.

The oxidative dehydroaromatization (ODA) of 1,2,3,4-tetrahydroquinoline (THQ) is a highly atom economic route for the synthesis of quinoline, a privileged N-heterocyclic motif in the pharmaceutical industry, while requiring stoichiometric strong oxidants and noble metal catalysts. Amine oxidase (AO)-catalyzed oxidative dehydroaromatization of THQs is a sustainable alternative but still suffers from low activity and a narrow substrate scope. Herein, a novel amine oxidase from Vibrio sp. JCM 19236 (VsAO) was obtained by gene mining and its mutant M2(F368D/N127K) was obtained by protein engineering. VsAO exhibited higher ODA activity over the reported AOs due to the unique dual-tunnel structure for substrates/products entrance/exit. M2 exhibited higher enzyme activity owing to the narrowed port and enhanced positivity at the tunnel that is close to the isoalloxazine ring head of flavin adenine dinucleotide (FAD), pushing the substrate closer to the isoalloxazine catalytic center of FAD and leading to higher enzymatic activity and higher catalytic performance.