Green Chemistry最新文献

Activating lattice oxygen in oxygen evolution reactions (OER) serves as an effective strategy to overcome the inherent limitations of the traditional adsorbate evolution mechanism (AEM). Molybdenum dioxide (MoO₂), which has attracted attention due to its high electrical conductivity and other metallic properties, exhibits excessive adsorption of oxygen-containing intermediates at its elevated molybdenum d-band center. This leads to the formation of stable Mo–O bonds, thereby hindering the lattice oxygen mechanism (LOM). This study demonstrates that phosphorus doping serves as a more direct strategy for intrinsic electronic structure modulation. DFT calculations predict that phosphorus doping effectively lowers the d-band center of molybdenum and softens Mo–O bonds, thereby enabling lattice oxygen participation in the reaction mechanism. Consistent with the computational results, experimental kinetic studies (e.g., pH-dependent experiments) and chemical probe tests confirm that P-MoO₂ follows the LOM pathway. The prepared P-MoO₂ catalyst exhibits an overpotential of only 247 mV at 10 mA cm⁻² current density while maintaining stability for up to 100 hours. Furthermore, through various characterization techniques (TEM, XPS, in situ Raman spectroscopy), it was observed that the catalyst underwent significant potential-induced surface reconstruction during the reaction process, forming an amorphous MoO(OH)_x layer rich in Mo⁵⁺. This reconstructed layer is considered the true active phase, where Mo⁵⁺ has been confirmed as the dominant valence state in the OER process.

Thorium (Th) is a natural radioactive element often associated with rare earths. The efficient recovery of Th is not only essential for environmental protection, but also facilitates its potential reuse as a nuclear fuel. A graphite felt electrode modified with amidoxime (GF-AO) was synthesized for the electrochemical recovery of Th in this study. The GF-AO electrode demonstrated a high recovery capacity and excellent selectivity towards Th. Under the action of an electric field between the electrodes, the selectivity of separation between Th and rare earths was significantly improved. The physical and chemical recovery capacity of the GF-AO electrode for Th was 121.51 mg g⁻¹, while its electrochemical recovery capacity reached 3431 mg g⁻¹. The excellent capacity and selectivity of the GF-AO electrode provides a new approach for the green and efficient recovery of Th.

3′-Phosphoadenosine-5′-phosphosulfate (PAPS) and its precursor adenosine 5′-phosphosulfate (APS) are universal sulfate donors that underpin diverse sulfonation reactions and play pivotal roles in sulfur metabolism. As the central activated forms of sulfur, they serve as intermediates in the assimilation of inorganic sulfate into organic biomolecules and provide sulfonate groups for the structural diversification of natural products, glycosaminoglycans, and secondary metabolites. Recent advances have revealed new insights into their biosynthetic routes, regulatory mechanisms, and enzymatic systems, along with innovative strategies for their regeneration and application. Progress in metabolic engineering has enabled efficient PAPS/APS supply and recycling, while high-throughput sulfotransferase screening, structure-guided protein engineering, and rational synthetic pathway design have expanded the toolkit for tailoring sulfonation patterns with enhanced specificity and catalytic performance. In this review, we critically summarize advances in PAPS/APS biosynthesis, highlight emerging approaches for synthetic pathway design and sulfotransferase discovery, and discuss their implications for the sustainable biomanufacturing of sulfated natural products. Particular emphasis is placed on the convergence of synthetic biology, enzyme engineering, and systems-level metabolic design, which together offer powerful opportunities to expand the chemical space of sulfated compounds. These developments not only deepen our understanding of sulfur assimilation and its regulation but also open new prospects for engineering sulfation pathways toward the scalable, green, and economically viable production of high-value sulfated metabolites.

The utilization of external fields to enhance electrochemical catalytic reactions has emerged as a promising approach in recent times. In this study, a multi-field coupling strategy involving light, heat, and magnetism is proposed to promote the electrocatalytic hydrogen evolution reaction (HER). A ferromagnetic CoFe₂O₄ modified MoS₂ (CoFe₂O₄/MoS₂) with a distinct photothermal effect is employed as a model catalyst. When an external magnetic field and light field are synergistically integrated into the electrochemical system, there is a remarkable reduction of about 50% in the overpotential. Specifically, an overpotential of 64 mV is achieved at a current density of 10 mA cm⁻². To further investigate the magnetic sensitivity of the ferromagnetic catalyst, the catalyst substrates are replaced with Mo₂C and ZnCdS, and the results indicate that the ferromagnetic catalyst shows significant sensitivity to external magnetic fields. The performance improvement can be attributed to multiple factors. Firstly, the application of a magnetic field enhances electron spin polarization, which in turn facilitates electron transfer kinetics. Secondly, the magnetohydrodynamic (MHD) effect causes the charged particles to move in a spiral manner, which modulates the local environment at the catalyst–electrolyte interface by forming spiral flow H₂ bubbles. Moreover, infrared thermal imaging confirms that the application of a magnetic field intensifies the photothermal effect of CoFe₂O₄/MoS₂. The resulting phonon bottleneck effect suppresses phonon relaxation, providing additional thermal energy and consequently reducing the reaction barrier. This work proposes an innovative multi-field synergistic approach for constructing highly active non-precious metal electrocatalysts.

A palladium-catalyzed reductive carbonylative benzannulation of 1,4-enynes with carbon dioxide (CO₂) as carbonyl source has been developed for the first time, offering an efficient approach to a wide range of multi-substituted phenols in high yields. The success of this transformation hinges on a synergistic dual silane reduction system: one silane acts as a reductant for the conversion of CO₂ to CO, while the other serves as a hydrogen source to generate Pd–H species. This method is operationally simple, exhibits broad substrate scope, and can be applied to the late-stage modification of complex pharmaceutical molecules as well as the synthesis of bioactive compounds such as thymol.

Rifamycin O (RO), a key intermediate in the antibiotic drug rifaximin synthesis, faces several production challenges including low yield, purity issues, and environmental concerns. Here, we report an electrochemical synthesis strategy for achieving RO production via electrooxidation of rifamycin B (RB), resulting in a 92% high yield. Trace water addition improves the functional-group compatibility during RB electrooxidation, substantially elevating the RO yield by 10%. Mechanistic studies reveal that trace water regulates methanol's hydrogen bond network, facilitates the dissociation of the hydroxyl group in the carboxylic acid, and enriches RB at the electrode/electrolyte interface, thereby achieving thermodynamic and kinetic synergistic optimization of RB electrooxidation. Systematic optimization of flow electrolyzer parameters further improves the performance. The scale-up experiment with an electrode area of 400 cm² demonstrates high yield and space–time yield. The present work establishes the electrochemical synthesis of RO, providing a sustainable paradigm for pharmaceutical electrosynthesis.

Lignin can significantly promote gel formation and enhance the properties of the resulting gels due to its rigid structure and abundant functional groups. Herein, high-purity (91.28%) lignin with a low and uniform molecular weight (M_w = 4071 g mol⁻¹, M_n = 2770 g mol⁻¹, PDI = 1.46) was effectively separated from natural bamboo using deep eutectic solvents (DESs). The obtained DES-separated bamboo lignin (DESL) was dissolved in different DES systems, including betaine/ethylene glycol (Bet/EG) DES and choline chloride/ethylene glycol (ChCl/EG) DES via a green and mild one-pot approach to fabricate two kinds of DES gels, Fe-L-GO/PAA and L/PAA, respectively. The abundant active sites and dispersibility of DESL enabled the formation of a dense and uniform hydrogen-bonded network within both Fe-L-GO/PAA and L/PAA. This network enhanced the polymeric structure of two gels, thereby significantly improving their conductivity, toughness, and stability. Meanwhile, the phenolic hydroxyl groups of DESL improved the long-term and repeatable adhesion of gels, while its aromatic structures endowed the gels with UV resistance. These properties extended the service life of the gels. Among the two gels, Fe-L-GO/PAA exhibited a higher tensile strength of 246.3 kPa and a lower glass transition temperature of −117.4 °C, making it suitable for use in flexible electronic devices at low temperatures. Moreover, L/PAA achieved a higher conductivity (7.41 mS cm⁻¹), elongation at break (712.9%), and compressive strength (2.5 MPa). These properties satisfy the requirements for accurate electrical signal transmission for flexible electronic materials under large-scale deformation. In general, this study extracted high-quality bamboo lignin using DES and employed it to fabricate green DES gels, which exhibit outstanding performance outdoors or in harsh environments.

Green hydrogen produced via renewable-powered water electrolysis is widely regarded as environmentally sustainable, yet existing life cycle assessments often differ in their treatment of upstream supply chain processes. This study evaluates four major electrolysis technologies—alkaline, proton exchange membrane, solid oxide electrolysis cell, and anion exchange membrane —using a harmonized cradle-to-gate framework that systematically incorporates all relevant upstream emission categories. Across all technologies, upstream supply chain emissions (scope 3) contribute 15–49% of total greenhouse gas burdens, underscoring their substantial influence on life cycle outcomes. Environmental performance is shaped by material requirements, operational efficiency, and component manufacturing intensity, with critical raw materials such as platinum, nickel, and high-temperature alloys emerging as major upstream drivers. Under a net-zero mitigation scenario in which conventional grid electricity is replaced with renewable electricity, total life cycle emissions decrease by 79–90% across all electrolysis technologies. Nevertheless, upstream supply chain processes remain significant contributors, indicating that electricity decarbonization alone is insufficient. Material efficiency, low-carbon manufacturing routes, durability improvements, and recycling strategies are essential to meaningfully reduce the carbon footprint of green hydrogen. Emerging technologies such as AEM demonstrate promising environmental potential owing to their balanced material profiles and reduced dependence on supply-constrained critical materials. This study provides a harmonized methodological foundation for evaluating the environmental performance of water electrolysis systems and highlights that achieving truly sustainable green hydrogen requires coordinated advances in supply chain decarbonization, technological efficiency, and renewable electricity integration.

The growing demand for sustainable extraction approaches has positioned deep eutectic systems (DESs) as promising, and often greener, alternatives to conventional solvents for valorizing algal and cyanobacterial biomass. This systematic review, supported by quantitative data integration and multivariate statistical analysis, analyzes peer-reviewed studies on the recovery of proteins, carbohydrates, lipids, fatty acids, phytosterols, polyphenols, and pigments from microalgae, macroalgae, and cyanobacteria, and highlights the main challenges in applying DESs to biomass processing. To ensure comparability, extraction conditions, DES composition, biomass origin, and assisted extraction techniques were systematically examined, with results normalized across studies. Hydrophilic DESs, typically based on choline chloride, sugars, or glycerol, generally show high efficiency for proteins and phycobiliproteins, whereas hydrophobic systems derived from fatty acids or terpenes favor the extraction of lipids and lipophilic pigments. However, water content, viscosity, and biomass-solvent interactions can significantly modulate these trends, and deviations are reported. Ultrasound-assisted extraction is among the most frequently employed techniques to enhance DES extraction. Principal component analysis revealed clear clustering of algal species and DES formulations according to compound class, confirming polarity-driven selectivity for specific macronutrients, pigments and phenolics. Beyond selective extraction, DESs and natural DESs (NADESs) support biomass pretreatment and stabilization, and can mitigate off-flavors and odors, thus reducing both energy and solvent consumption while aligning with circular-economy principles. Although further research is required to address scalability and standardization, DES-based algal processing holds strong potential as a practical and sustainable route to producing functional ingredients.

Photochemical organic synthesis has emerged as a prominent and important synthetic methodology in recent years. However, conventional photosensitizers are often expensive and require multi-step synthesis for their preparation. This study utilizes natural flavonoids extracted from citrus peel (Tangeretin, Nobiletin, and Sinensetin) as photocatalysts to achieve the photooxidation of alkenes. Conversion rates of 53.7% for styrene and 66.1% for cyclohexene were attained. Reaction Mechanism Generator (RMG) simulations revealed that alkenes undergo reaction pathways mediated by singlet oxygen or oxygen-free radicals to form the corresponding products, a finding corroborated by a series of control experiments and EPR. These flavonoid compounds exhibit Aggregation-Induced Emission (AIE) characteristics. Upon encapsulation with saponins to form nanoparticles, the conversion rate for cyclohexene was further enhanced to 86.0%. Furthermore, this system successfully achieved the efficient oxidation of benzyl alcohol in an aqueous solvent (52.4% conversion, >99% selectivity). This work establishes a comprehensive green chemistry system encompassing the light source, catalyst, and solvent. The proposed strategy offers a novel approach to the development of natural photocatalysts and sustainable organic synthesis.