Green Energy&Environment

Degradation and utilization of polyvinyl chloride (PVC): Challenges and opportunities toward a circular economy

Rui Huang, Jiaolong Meng, Xuefeng Jiang — 2025-10-28

Rui Huang, Jiaolong Meng, Xuefeng Jiang Polyvinyl chloride (PVC) poses persistent environmental and recycling challenges due to its high chlorine content, complex additives, and structural resistance to degradation. Recent research has shifted focus from traditional disposal methods toward chemically informed strategies that valorize PVC within the framework of a circular economy. This review systematically summarizes three emerging pathways for PVC transformation. The first involves catalytic deconstruction into small molecules such as chlorinated olefins, hydrocarbons, and oxygenates through thermal, photocatalytic, and electro-assisted processes. The second explores backbone-preserving reconstruction into functional materials, including porous carbons, membranes, ion-conducting films, and vitrimer-type polymers by leveraging selective dechlorination and structural reprogramming. The third addresses the co-processing of PVC with mixed plastic wastes through synergistic catalytic systems that tolerate chlorine-rich streams and promote selective transformation. Across all pathways, emphasis is placed on structure–property correlations, chlorine management, additive compatibility, and downstream utility. Summary tables and schematic diagrams are included to compare system efficiencies, product selectivities, and application scopes. By integrating mechanistic understanding with materials innovation, this review highlights how PVC can be reimagined as a tunable molecular platform rather than a persistent pollutant. Green Energy&Environment. 2026 11(2): 283-316.

Entropy-driven design of multifunctional electrocatalysts: Advances and perspectives in high-entropy materials

Ning Wei, Sufeng Zhang, Xue Yao, Scott Renneckar — 2025-10-22

Ning Wei, Sufeng Zhang, Xue Yao, Scott Renneckar High-entropy materials (HEMs) have attracted extensive attention in the field of electrocatalysis due to their high performance enabled by their multi-component, tunable structural characteristics and excellent stability. HEMs are usually composed of five or more metal elements, and have core advantages such as high configurational entropy, lattice distortion and multi-element synergistic effect, which provide new possibilities for composition regulation and performance optimization of catalysts. Especially at the nanoscale, HEMs show a larger specific surface area, abundant active sites and higher catalytic reaction efficiency, further expanding their application potential in electrochemical reactions. This paper systematically reviews the classification, structure construction and regulation strategies of HEMs, and focuses on their research progress in critical electrocatalytic reactions including water splitting (HER, OER), hydrogen oxidation (HOR), oxygen reduction (ORR), carbon dioxide reduction (CO₂RR), nitrate reduction (NO₃⁻RR) and electrooxidation of organics (EOO). In addition, the preparation methods of HEMs, the structure–performance relationship and the entropy regulation mechanism in the catalytic process are analyzed. Finally, this paper proposes the key challenges currently faced by HEMs in electrocatalytic applications and looks forward to their future development direction, providing a theoretical basis and design ideas for building a new generation of efficient and sustainable electrocatalysts. Green Energy&Environment. 2026 11(2): 317-358.

Ambient-air fabrication of perovskite solar cells: Challenges, progress, and perspectives

Xinyu Gu, Xiang Zhang, Dongxu Ren, Yixin Zhao, Hao Chen — 2025-12-04

Xinyu Gu, Xiang Zhang, Dongxu Ren, Yixin Zhao, Hao Chen Perovskite solar cells (PSCs) have emerged as a revolutionary photovoltaic technology due to their exceptional optoelectronic properties and low-cost solution processability, yet their fabrication typically demands stringent inert conditions to mitigate environmental degradation. However, achieving efficient and stable PSC fabrication in ambient air is crucial for their widespread commercialization, as it significantly reduces manufacturing costs, simplifies process flow, and enables scalable roll-to-roll and printing techniques. The main challenges hindering ambient processing include moisture-induced degradation, oxygen-related oxidation, and humidity-driven variations in crystallization kinetics, which often lead to reduced film quality, defective interfaces, and limited device performance. Recent advancements in ambient-air processing of PSCs present a promising pathway toward scalable and eco-friendly manufacturing, though challenges such as moisture sensitivity, oxygen-induced degradation, and crystallization control remain. This review examines ambient-air effects on perovskite formation, device performance, and stability, alongside strategies for improvement via compositional engineering, solvent optimization, and novel deposition methods. Furthermore, we discuss the progress in lab-scale and large-scale ambient-air fabrication methods, emphasizing their potential for industrial translation. Finally, we outline future research directions to enhance the efficiency, stability, and commercial viability of air-processed PSCs, underscoring their critical role in sustainable energy development. Green Energy&Environment. 2026 11(2): 359-386.

From photo-assisted to photo-rechargeable: Advancing Zn-Ion batteries with light-driven energy storage

Dan Yang, Chen Xin, Hua-Kun Liu, Yaoxin Zhang, Ting Xiong — 2025-12-15

Dan Yang, Chen Xin, Hua-Kun Liu, Yaoxin Zhang, Ting Xiong Solar energy represents a transformative, inexhaustible, and eco-friendly solution for sustainable power generation. However, its intermittent nature requires efficient energy storage technologies to maximize utilization. A promising approach involves integrating photoactive materials into the cathodes of zinc-ion batteries (ZIBs), enabling direct solar energy capture and storage while improving electrochemical performance. This review systematically explores the emerging field of light-driven ZIBs (LDZIBs), focusing on two main operational modes: photo-assisted ZIBs (PAZIBs), where light enhances battery performance, and photo-rechargeable ZIBs (PRZIBs), which can be directly charged by light without external power sources. We comprehensively examine the classification, working mechanisms, and material integration strategies for these systems. Key advances in electrode design, innovative materials, and potential application scenarios for both PAZIBs and PRZIBs are highlighted. Finally, we discuss the major challenges and future research directions aimed at improving the efficiency, stability, and scalability of LDZIBs to facilitate their commercialization as a cornerstone technology for future solar energy storage. Green Energy&Environment. 2026 11(2): 387-400.

Exploring critical development in photocatalytic overall water splitting: Recent trend, races predictions and environmental impacts

2025-12-17

Zeeshan Ajmal, Muhammad Haseeb Ullah, Abdul Qadeer, Huanhuan Zhang, Muhammad Abubaker Khan, Shenjie Shen, Yasin Orooji, Mohd. Imran, M.K.M. Ali, Ramadan Taha, Junmin Li, Shirong Lu, Waseem Abbas, Shuhang Wang Despite intensive research on solar-driven photocatalytic overall water splitting (POWS), the overall efficiencies remain insufficient to meet commercial standards. As a central challenge in realizing this technology mainly lies in the precise tuning and rational designing of highly efficient materials and photocatalytic systems, which is paramount for its unlocking scalable, practical applications. However, novel materials fabrication and advanced photocatalytic systems are essential for overcoming intrinsic limitations of conventional catalysts by enabling this green technology to resolve global energy crisis. Therefore, this review critically explores the engineering developments in POWS process and novel photocatalyst designing, via shifting from simple bandgap engineering to more advanced charge carrier dynamics control via utilizing one/two-step photocatalytic excitation system, surface phase junctions i.e., Z-scheme and S-scheme heterojunctions, surface modification, morphological tuning, and the role of co-catalysts, to control sluggish kinetics, promote oxygen evolution reaction (OER) and suppress undesirable H₂/O₂, backward reaction with superior visible light absorption capacity to produce remarkable energy production. Moreover, we critically discuss the recent trend of POWS from a materials discovery phase to demanding engineering and mechanistic optimization phase with viable economic viability, which requires bridging the gap between excellent lab-scale performance to stringent stability, cost, and high efficiency demands of industrial-scale solar fuel production. In addition, the currents challenges and future directions are also enclosed in detail for sustainable energy production. Green Energy&Environment. 2026 11(2): 401-453.

Acetone-mediated glucose isomerization over a ZrO₂-NC composite catalyst

Mi Gao, Hongquan Fu, Wenhua Zhang, Zhicheng Jiang, Bi Shi — 2025-07-25

Mi Gao, Hongquan Fu, Wenhua Zhang, Zhicheng Jiang, Bi Shi The agglomeration–prone properties of metal oxide catalysts limit their catalytic efficiency in the isomerization of glucose to fructose. Herein, the hierarchical structure and abundant coordination groups of collagen fibers were used to anchor Zr⁴⁺, and a highly dispersed ZrO₂-nitrogen-doped carbon (ZrO₂-NC) composite catalyst was subsequently fabricated by calcination. For the catalytic glucose-to-fructose isomerization over ZrO₂-NC, fructose was obtained in 41.3% yield and 85.3% selectivity in a water-acetone solvent at 120 °C for 10 min. The electron-deficient environment of ZrO₂ surface during charge transfer from ZrO₂-to-NC layer facilitated the preferential adsorption of glucose, which accelerated glucose isomerization and fructose desorption. The amphoteric catalyst triggered both proton transfer on the Bronsted base sites and the intramolecular hydride shift of glucose on the Lewis acid sites of ZrO₂-NC in the mixed solvent. The latter isomerization mechanism depended on the presence of acetone, which lowered the energy barrier and increased fructose yield. Green Energy&Environment. 2026 11(2): 454-463.

Boosting redox kinetics in CoS/Ti₃C₂ heterostructure via interfacial charge redistribution for high-energy-density supercapacitors

2025-07-25

Yu Liu, Mengjie Pan, Mengqin Gong, Huachen Lin, Yulong Ying, Longhua Li, Hong Jia Supercapacitors are indispensable for next-generation energy storage, achieving high energy density and long-term durability remains a formidable challenge. Conventional CoS suffers from poor conductivity, while Ti₃C₂ faces severe restacking. Herein, we report a novel synthesis strategy that integrates metal–organic framework (MOF) growth with electrostatic self-assembly to construct heterojunction of CoS nanotubes coated with ultrathin Ti₃C₂ nanofilms. Material characterization via SEM, TEM, XRD, and XPS systematically confirms the heterostructure formation, and chemical composition. This rational design synergistically leverages CoS high pseudocapacitance and Ti₃C₂ metallic conductivity while the heterostructure mitigates restacking, enhances charge transfer, and stabilizes interfacial interactions. Density functional theory (DFT) calculations reveal strengthened OH⁻ adsorption at the Co–Ti interface (E_ad = 1.106 eV). Consequently, the CoS/Ti₃C₂@CC delivers a remarkable specific capacitance of 1034.21 F g⁻¹ at 1 A g⁻¹. Assembled into a supercapacitor, CoS/Ti₃C₂@CC//AC achieves a high energy density of 74.22 Wh kg⁻¹ at 800 W kg⁻¹, maintaining 89.13% initial capacitance after 10,000 cycles. Significantly, it exhibits a remarkably low leakage current (0.23 μA) and ultra-prolonged voltage retention (47.14% after 120 h), underscoring exceptional durability. This work pioneers a rational heterostructure engineering strategy by integrating MOF-derived architectures with conductive MXene nanofilms, offering critical insights for the development of ultra-durable supercapacitors. Green Energy&Environment. 2026 11(2): 464-477.

High-valent cobalt-oxo species mediated selective oxidation of glucose to chemicals in photocatalytic Fenton-like system

2025-08-21

Tianliang Xia, Chengxu Wang, Xinyu Bai, Meiting Ju, Hengli Qian, Ruite Lai, Chao Xie, Guanjie Yu, Yao Tang, Fei Qu, Chaojie Zhang, Shuwen Zhou, Haijiao Xie, Shaolan Song, Qidong Hou Peroxymonosulfate (PMS)-based Fenton-like technologies have been increasingly employed in the upgrading of biomass, but they are commonly limited by the trade-off between conversion and selectivity due to the short lifetime of reactive oxygen species (ROS) and uncontrollable oxidation pathways. Herein, we show that single-atom Co supported on carbon nitride enables the high-valent-oxo cobalt species (Co(IV)O) mediated oxidation of glucose into value-added products in acetonitrile. This photocatalytic Fenton-like system achieved an overall selectivity of gluconic acid, glucaric acid, arabinose, and formic acid up to 90.3% at glucose conversion of 69.6%, outperforming most of previously reported catalytic systems. The small amount (0.72 wt%) of single-atom Co could not only elevate the optical absorption and the efficiency of photo-generated carriers separation but also induce the efficient generation of Co(IV)O with reduced ROS to enable efficient and selective oxidation. These findings prove the great promise of high-valent metal-oxo species in biomass conversions. Green Energy&Environment. 2026 11(2): 478-487.

Manipulating and unveiling contributions of the reactive oxygen species dramatically promote selective photo-oxidation of 5-hydroxymethylfurfural into 2,5-furandicarboxylic acid in aqueous solution

Runqing Xiao, Qingmao Yang, Yanjie Li, Wei Zhang, Gang Xiao, Chun Shen — 2025-07-30

Runqing Xiao, Qingmao Yang, Yanjie Li, Wei Zhang, Gang Xiao, Chun Shen Achieving high selectivity to 2,5-furandicarboxylic acid (FDCA) in the photocatalytic oxidation of 5-hydroxymethylfurfural (HMF) in aqueous solution advocates the principle of green and sustainable chemistry, but still remains a significant challenge. Herein, manipulating the reactive oxygen species (ROS) has been realized and dramatically promotes the selective photocatalytic oxidation of HMF in aqueous solution. A high FDCA yield of 98.6% has been achieved after 3 h of visible light irradiation over the as-prepared FeO_x-Au/TiO₂ catalyst, being one of the leading photocatalytic performances. Furthermore, satisfactory FDCA yields of higher than 80% could be realized even in the outdoor environment under natural sunlight irradiation, regardless of sunny or cloudy weather. A combination study including physical characterization, kinetic analysis, radical trapping experiments and density functional theory calculations unveils the rate-determining step (oxidation of hydroxyl group) and respective contributions of the generated ROS (¹O₂ and ·O₂⁻) in each step of the entire reaction network. The present work would push ahead the understanding of HMF photocatalytic oxidation and contribute to the rational design of high-performance photocatalysts. Green Energy&Environment. 2026 11(2): 488-499.

Insight into properties and structures of ionic liquids by machine learning molecular dynamics simulation

Yaxi Yu, Zhenlei Wang, Xiaochun Zhang, Kun Dong — 2025-06-10

Yaxi Yu, Zhenlei Wang, Xiaochun Zhang, Kun Dong Ionic liquids (ILs) have exhibited great application potential in many fields due to their unique properties. Molecular dynamics (MD) simulation has been widely employed to investigate their microscopic structure. However, classical molecular dynamics simulations struggle to accurately describe the complex interactions in ILs using the existing parameterized force fields. Recently, the MD simulations based on machine learning force fields (MLFFs) trained by first-principles calculations have attracted considerable attentions due to their abilities to balance computational accuracy and efficiency. Herein, we report the Bayesian-based MLFFs which can be successfully applied in IL systems and accelerate MD simulation. The calculated atomic forces, structures, and vibrational behaviors were validated to match the accuracy of first-principles calculations. Properties of the imidazolium-based ILs, including density, self-diffusion coefficients, viscosity, and radial distribution functions were predicted at the extended scales. Z-bonds that describe the unique structures in ILs were analyzed and the influences of C-positions, temperature, and solvent H₂O on Z-bonding configurations were systematically investigated. Our results confirmed that MLFFs presented the strong feasibility to investigate the large and complex systems, especially to predict structures and properties of the ILs. And the procedure described for MLFFs provides valuable guidance for researchers who are studying ILs. Green Energy&Environment. 2026 11(2): 500-510.

Enhancing carbonization of microcrystalline cellulose through ball milling under decoupled temperature and pressure hydrothermal conditions

Kaile Li, Jiahui Hu, Zhiqiang Xu, Shijie Yu, Qinghai Li, Yanguo Zhang, Hui Zhou — 2025-07-28

Kaile Li, Jiahui Hu, Zhiqiang Xu, Shijie Yu, Qinghai Li, Yanguo Zhang, Hui Zhou Hydrothermal treatment of cellulose is a promising green route for bioenergy and biochemical production, yet it requires investigation of the underlying mechanisms. In this study, the effects of cellulose crystallinity and decoupled temperature and pressure conditions on cellulose conversion and product distribution were investigated. Microcrystalline cellulose was ball-milled for varying durations, leading to a reduction in crystallinity, with 4 h of milling sufficient to achieve near-complete amorphization. Unlike concurrent recrystallization and hydrolysis observed under autogenous pressure, decoupled conditions significantly accelerated hydrolysis of cellulose. Notably, lower crystallinity cellulose exhibited significant improvements in glucose and 5-HMF yields, with 4-h ball milling showing optimal performance among all samples. Furthermore, carbon sub-micron spheres were largely produced, which were confirmed via PTFE encapsulation experiments to primarily consist of secondary char deriving from re-polymerization and condensation reactions of the liquid phase. Overall, this study demonstrates that lower crystallinity not only facilitates hydrolysis but also accelerates the carbonization processes under decoupled pressure conditions, highlighting its potential for efficient biomass conversion into valuable products. Green Energy&Environment. 2026 11(2): 511-522.

CdS-enzyme composite promotes photobiocatalytic conversion of plastic-derived lactate to chiral chemicals

2025-07-31

Willy W.L. See, Phuc T.T. Nguyen, Heng Yih Tan, Jie Fu Jeff Zhou, Sie Shing Wong, Kang Zhou, Ning Yan The combination of photo- and bio-catalysis in one-pot enables sustainable, visible-light driven cascade reactions for the synthesis of value-added chiral chemicals under mild conditions. Despite the attractiveness of merging the redox capability of heterogeneous photocatalysts with the excellent enantioselectivity of enzymes, developing such a reaction under one-pot conditions poses a challenge due to catalyst incompatibility. In this study, a cadmium sulfide (CdS)-enzyme composite was engineered for one-pot conversion of plastic-derived lactate into chiral compounds. By coating CdS onto alginate beads, its redox capability for the oxidation of lactate in water under visible light was preserved. The generated pyruvate subsequently underwent enantioselective transformation catalyzed by encapsulated enzymes within the beads, producing (R)-acetoin, l-alanine, or (R)-phenylacetylcarbinol. The core–shell structure of the CdS-enzyme composite protects the enzymes against radical attacks and facilitates recycling, yielding 81% of (R)-acetoin achieved after four reaction cycles. Additionally, we demonstrated an upcycling process converting post-consumer polylactic acid cups into (R)-acetoin. This work introduces a novel approach for integrating photocatalysts and enzymes to synthesize chiral chemicals from end-of-life plastics. Green Energy&Environment. 2026 11(2): 523-530.

Harnessing tunable lignin-based carbon quantum dots for sustainable water purification

2025-07-24

Xinyan Hou, Pengfei Zhou, Jun Guo, Shenao Yuan, Shiman Chen, Heyu Chen, Xiao Xiao, Jikun Xu, Feng Peng Developing on-demand biomass valorization represents an ideal path to alleviate the double burden of a sustainable energy-environment future, yet exploring tunable lignin-first chemistry to accomplish multifunctional water purification remains elusive. Herein, we report a versatile solvent-fractionation to construct heteroatom-doped multicolor lignin carbon quantum dots (CQDs) with the functions of bimodal pollutant sensing, metal-ionic visualization, and photocatalytic antibiotic dissociation. With the aid of oxidation cleavage and biphasic extraction, the underlying lignin features of molecular weight and functional linkages influence the quantum size and core-surface state of CQDs conferring the unique optical-structure–performance. The N, S co-doped blue-emitting CQDs via light-quenching offer the selective identification of Fe³⁺-ions in a broad response range with an acceptable limit of detection. The addition of L-cysteine can efficiently restore the fluorescence of CQDs by forming a stable Fe³⁺-L-cys complex. The green-emissive CQDs are facilely embedded into cellulose hydrogel to directly visualize the presence of metal-ions. A red-CQDs modified ternary ZnIn₂S₄ (ZIS) composite is fabricated to achieve photocatalytic antibiotic removal with an efficiency of ∼85%. The excellent photo-generated electron and storage capabilities of CQDs improve the light-capturing, electron conduction, and charge carrier separation of ZIS. The reactive species are of importance to photocatalytic tetracycline oxidation, wherein the electron holes (h⁺) function as the main contributor followed by ⋅O₂⁻, ¹O₂ and ⋅OH. The directly interfacial electron escaping-shuttling with the help of optimized electronic and energy-band structures is confirmed via electrochemical test and theoretical computation. We anticipate that the present work not only sheds substantial light to manipulate polychromatic lignin-based CQDs via a tailored solvent-engineering, but also presents an emerging green route of emphasizing biomass-water nexus. Green Energy&Environment. 2026 11(2): 531-544.

Synergistic Brønsted and Lewis acid sites for selective catalytic valorization of isopropanol from VOC streams

2025-09-15

Honghong Zhang, Zhiwei Wang, Lu Wei, Zhiquan Hou, Yuxi Liu, Hongxing Dai, Zhenxia Zhao, Jiguang Deng Directional catalytic transformation of volatile organic compounds (VOCs) into value-added chemicals represents a more sustainable strategy than complete mineralization, as it simultaneously mitigates environmental pollution and reduces carbon emissions. The primary challenge in achieving multifunctional olefin production from alcohol-type VOCs is the lack of mechanistic clarity, which hinders the targeted synthesis of selective catalysts. Herein, we developed W–Ti hybrid metal oxide catalysts (WTiO_x) with active Ti–O–W interfaces via a one-step hydrothermal synthesis and demonstrated their effectiveness for isopropanol conversion processes. Remarkably, WTiO_x-500 achieved 99.8% isopropanol conversion and 99.3% propylene yield at 140 °C, significantly outperforming TiO₂ (98.4% yield at 180 °C) and WO₃ (90.5% yield at 240 °C). WTiO_x-500 also displayed higher thermal stability, with isopropanol conversion and propylene yield decreasing by 1.0% and 1.6% after 35 h on-stream reaction. Although impurities (e.g., CO₂, HCl, SO₂) caused partial deactivation of WTiO_x-500, oxygen treatment regenerated the catalyst. A series of characterization techniques indicated that the controlled calcination temperature promoted the formation of an optimal Ti – O – W interface in WTiO_x-500 through W substitution into the TiO₂ lattice and WO₃–TiO₂ surface interaction, where W species effectively tuned the electronic structure. This configuration endowed WTiO_x-500 with moderate acidity of Brønsted (−OH) and Lewis (Ti⁴⁺/W⁶⁺) acid sites, which synergistically facilitated charge transfer between isopropanol and catalyst, accelerated C–O bond cleavage during dehydration. This work provides mechanistic insights into isopropanol dehydration and demonstrates a potential approach for VOC valorization. Green Energy&Environment. 2026 11(2): 545-556.

Defect engineering of TiO₂ for efficient photocatalytic transfer hydrogenation with palladium as cocatalyst and water as a hydrogen source

2025-09-18

En Zhao, Jingyuan Su, Hehe Fan, Bing Nan, Lina Li, Haifeng Qi, Weiwei Fang, Wenjun Zhang, Zupeng Chen Photocatalytic transfer hydrogenation using water as the proton source has emerged as an attractive and green approach for the catalytic reduction of unsaturated bonds. Herein, we report an oxygen-defective TiO₂-supported palladium catalyst (Pd–TiO₂-O_v) for efficient photocatalytic water-donating transfer hydrogenation of anethole towards 4-n-propylanisole in a high yield of 99.9%, which is significantly higher compared to the pristine TiO₂-supported palladium catalyst (Pd–TiO₂, 74%). The enhanced performance is ascribed to the presence of oxygen vacancies, which facilitate light absorption and suppress the recombination of photogenerated electron–hole pairs. Furthermore, the Pd–TiO₂-O_v is versatile in hydrogenating various alkene substrates including those with hydroxyl, ether, fluoride, and chloride functional groups in full conversion, thus offering a green method for transfer hydrogenation of alkenes. This study provides new insights and advances in current hydrogenation technology with water as the proton source. Green Energy&Environment. 2026 11(2): 557-564.

Boosting efficient C–C coupling toward electrocatalytic acetate synthesis from CO₂ via close Cu⁺/Ag dual active sites

Ruifeng Wang, Yuchang Liu, Yandong Li, Yafen Kong, Qizhi Chen, Shuangliang Zhao — 2025-10-11

Ruifeng Wang, Yuchang Liu, Yandong Li, Yafen Kong, Qizhi Chen, Shuangliang Zhao Efficiency of C–C bond coupling in highly inert CO₂ is relatively low, which severely limits its efficient conversion to acetate. Here, we successfully developed a highly stable NF@CoMn₂O₄@Cu₂O–Ag bimetallic active site catalyst by anchoring Ag on the Cu₂O surface. In this catalyst, the Co³⁺/Mn³⁺–Mn⁴⁺ removes excess electrons from the Cu⁺ sites via strong electronic interactions, preventing the reduction of Cu₂O to metallic Cu⁰, which ensures the NF@CoMn₂O₄@Cu₂O–Ag exhibits a high resistance to deactivation. The Cu⁺ active sites of NF@CoMn₂O₄@Cu₂O–Ag efficiently electroreduce CO₂ to the ∗CO_atop intermediate, while the Ag active sites efficiently electroreduce CO₂ to the ∗CO_bridge intermediate. The proximity of Cu⁺/Ag bimetallic sites shortens the distance for C–C bond coupling between the ∗CO_atop and ∗CO_bridge intermediates, facilitating the efficient electrocatalytic coupling of CO₂ to synthesize acetate. DFT analysis indicates that the ΔG required for C–C bond coupling on the short-distance Cu⁺/Ag bimetallic sites of NF@CoMn₂O₄@Cu₂O–Ag is significantly lower than that of NF@CoMn₂O₄@Cu₂O, enabling a high Faradaic efficiency of 64.97% for acetate production at −0.3 V vs. RHE. This study provides an effective strategy for the rational design of synergistic catalysis between heterometallic catalytic sites to efficiently achieve C–C coupling for the synthesis of C₂₊ products. Green Energy&Environment. 2026 11(2): 565-577.

Structure–activity relationship in periodate activation by Fe–MOFs: Why MIL-101(Fe) outperforms other MIL-series in antibiotic degradation

2025-10-16

Ning Liu, Jingwen Xu, Yixuan Zhai, Ziyi Zhang, Yi Dang, Yusong Cao, Zhe Li, Wenyuan Huang, Xiaodong Zhang, Liang Tang Antibiotics are emerging pollutants that pose significant risks to environmental and human health. Periodate (PI)-based advanced oxidation processes have shown promise for their effective degradation. In this study, we systematically investigate the structure–activity relationship of four representative Fe-based metal–organic frameworks (Fe–MOFs)—MIL-101(Fe), MIL-88B(Fe), MIL-88A(Fe), and MIL-53(Fe)—as PI activators for tetracycline (TC) degradation. Among them, MIL-101(Fe) exhibited the highest catalytic performance, owing to its unique Fe₃O–OH nodes and mesoporous architecture. The MIL-101(Fe)/PI system achieved 93.3% TC degradation and 55.9% mineralization rate within 60 min. Mechanistic studies combining scavenger quenching, sulfoxide probe transformation, X-ray photoelectron spectroscopy, and X-ray absorption fine structure confirmed the generation of multiple reactive oxygen species, and high-valent Fe(IV)O and O₂^·⁻ played major roles in the tetracycline degradation process. Density functional theory calculations further revealed that MIL-101(Fe) and MIL-88B(Fe) effectively interact with PI to form Fe(III)-superoxide (Fe(III)–O–O^·⁻), a key intermediate in Fe(IV)O generation. In contrast, the adsorption energy of MIL-53 (Fe) and MIL-88A (Fe) was relatively weak, with fewer binding sites, resulting in poor performance. The synergy between Fe(III)–O–O^·− formation and the pore accessibility of MIL-101(Fe) accounted for its superior catalytic efficiency. This work not only clarifies the structural factors governing PI activation in Fe–MOFs, but also proposes a mechanistically informed strategy for designing high-performance catalysts for antibiotic degradation. Green Energy&Environment. 2026 11(2): 578-590.