Pub Date : 2025-04-23DOI: 10.1021/acs.jpcc.5c01026
Baitao Su, Yite Liu, Linan Chen, Shunli Liang, Aishui Yu
Lithium iron phosphate (LiFePO4) has garnered significant attention as a key cathode material for lithium-ion batteries due to its exceptional safety, long cycle life, and environmentally friendly characteristics. However, its electrochemical performance is influenced by several factors, with the Li/Fe molar ratio being one of the key determinants. In this study, a series of LiFePO4 samples with Li/Fe molar ratios of 0.99, 1.00, 1.01, 1.03, 1.05, and 1.07 were synthesized via a solid-state method. The impact of varying the Li/Fe molar ratios on the physical and electrochemical properties of LiFePO4 was systematically investigated. The results indicate that at a Li/Fe molar ratio of 1.05, the material exhibits optimal electrochemical performance, achieving a discharge capacity of 165.30 mA h g–1 at a 0.1 C rate and 158.38 mA h g–1 at a 1 C rate. A range of characterization techniques, including electrochemical impedance spectroscopy (EIS), differential capacity versus voltage (dQ/dV), and galvanostatic intermittent titration technique (GITT), confirmed that the sample with a Li/Fe molar ratio of 1.05 exhibits the lowest polarization and the highest lithium ion diffusion coefficient (3.24 × 10–12 cm2 s–1). These results demonstrate that the optimal Li/Fe molar ratio of 1.05 expands the Li+ transport channels within the LiO6 octahedra, reduces polarization, and enhances lithium-ion diffusion, thereby improving the electrochemical performance of the material.
{"title":"Enhancing High-Rate Performance and Cyclability of LiFePO4 Cathode Materials for Lithium-Ion Batteries by Optimizing the Li/Fe Ratio","authors":"Baitao Su, Yite Liu, Linan Chen, Shunli Liang, Aishui Yu","doi":"10.1021/acs.jpcc.5c01026","DOIUrl":"https://doi.org/10.1021/acs.jpcc.5c01026","url":null,"abstract":"Lithium iron phosphate (LiFePO<sub>4</sub>) has garnered significant attention as a key cathode material for lithium-ion batteries due to its exceptional safety, long cycle life, and environmentally friendly characteristics. However, its electrochemical performance is influenced by several factors, with the Li/Fe molar ratio being one of the key determinants. In this study, a series of LiFePO<sub>4</sub> samples with Li/Fe molar ratios of 0.99, 1.00, 1.01, 1.03, 1.05, and 1.07 were synthesized via a solid-state method. The impact of varying the Li/Fe molar ratios on the physical and electrochemical properties of LiFePO<sub>4</sub> was systematically investigated. The results indicate that at a Li/Fe molar ratio of 1.05, the material exhibits optimal electrochemical performance, achieving a discharge capacity of 165.30 mA h g<sup>–1</sup> at a 0.1 C rate and 158.38 mA h g<sup>–1</sup> at a 1 C rate. A range of characterization techniques, including electrochemical impedance spectroscopy (EIS), differential capacity versus voltage (d<i>Q</i>/d<i>V</i>), and galvanostatic intermittent titration technique (GITT), confirmed that the sample with a Li/Fe molar ratio of 1.05 exhibits the lowest polarization and the highest lithium ion diffusion coefficient (3.24 × 10<sup>–12</sup> cm<sup>2</sup> s<sup>–1</sup>). These results demonstrate that the optimal Li/Fe molar ratio of 1.05 expands the Li<sup>+</sup> transport channels within the LiO<sub>6</sub> octahedra, reduces polarization, and enhances lithium-ion diffusion, thereby improving the electrochemical performance of the material.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"32 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143862313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-04-23DOI: 10.1021/acs.jpcc.5c01429
Abraham Colin-Molina, Gookyeong Jeong, C. Daniel Frisbie
We report the formation and characterization of molecular tunnel junctions based on self-assembled monolayers (SAMs) of a benzimidazole-substituted terphenylene dithiol in protonated and unprotonated states. Molecular junctions were formed using the conducting probe atomic force microscopy (CP-AFM) platform. The measured current–voltage (I–V) characteristics were well-fitted by the analytical off-resonance single-level model (orSLM), which yielded two key electronic structure parameters, the HOMO-to-Fermi level offset, εh, and the HOMO-metal coupling, Γ. Protonation of the SAM decreased εh and increased Γ, leading to an overall increase in junction conductance G using either Au or Pt contacts. Changes in εh were verified by ultraviolet photoelectron spectroscopy (UPS). In general, the results are consistent with prior reports that tunneling currents through SAM junctions are sensitive to chemical changes. They also demonstrate the effectiveness of the off-resonance single-level model for extracting quantitative electronic structure parameters associated with the junction in its protonated and unprotonated states.
{"title":"Quantitative Analysis of the Effects of Protonation on Tunneling Transport in Molecular Junctions Based on a Benzimidazole-Substituted Terphenylene Dithiol","authors":"Abraham Colin-Molina, Gookyeong Jeong, C. Daniel Frisbie","doi":"10.1021/acs.jpcc.5c01429","DOIUrl":"https://doi.org/10.1021/acs.jpcc.5c01429","url":null,"abstract":"We report the formation and characterization of molecular tunnel junctions based on self-assembled monolayers (SAMs) of a benzimidazole-substituted terphenylene dithiol in protonated and unprotonated states. Molecular junctions were formed using the conducting probe atomic force microscopy (CP-AFM) platform. The measured current–voltage (<i>I–V</i>) characteristics were well-fitted by the analytical off-resonance single-level model (orSLM), which yielded two key electronic structure parameters, the HOMO-to-Fermi level offset, ε<sub><i>h</i></sub>, and the HOMO-metal coupling, Γ. Protonation of the SAM decreased ε<sub><i>h</i></sub> and increased Γ, leading to an overall increase in junction conductance <i>G</i> using either Au or Pt contacts. Changes in ε<sub><i>h</i></sub> were verified by ultraviolet photoelectron spectroscopy (UPS). In general, the results are consistent with prior reports that tunneling currents through SAM junctions are sensitive to chemical changes. They also demonstrate the effectiveness of the off-resonance single-level model for extracting quantitative electronic structure parameters associated with the junction in its protonated and unprotonated states.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"18 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143862314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Daniel Glückman, Francesca Quinto, Claudia Joseph, Volker Metz, Karin Hain, Peter Steier, Horst Geckeis
Natural clay rocks, such as Opalinus Clay (OPA), are considered as potential host rocks for the disposal of high-level nuclear waste due to their ability to limit radionuclide transport to molecular diffusion. Laboratory studies related to the investigation of radionuclide diffusion behavior are usually performed at relatively high concentrations. For instance, U diffusion in clay rocks has been investigated at concentrations as low as approximately 10–4 mol·m–3 clay. This study addresses 233U(VI) diffusion in OPA down to ultratrace concentrations of 10–9 mol·m–3 using accelerator mass spectrometry. Fitting of the experimental data with a one-dimensional pore diffusion model revealed no significant changes in the U(VI) effective diffusion coefficient (De) over the investigated concentration range of 10–3 to 10–9 mol·m–3. Such concentration-independent behavior constitutes valuable information for the prediction of long-term U(VI) migration in geological repositories with OPA as host rock.
{"title":"Diffusion of U(VI) in Opalinus Clay Studied down to Ultratrace Levels","authors":"Daniel Glückman, Francesca Quinto, Claudia Joseph, Volker Metz, Karin Hain, Peter Steier, Horst Geckeis","doi":"10.1021/acs.est.4c12739","DOIUrl":"https://doi.org/10.1021/acs.est.4c12739","url":null,"abstract":"Natural clay rocks, such as Opalinus Clay (OPA), are considered as potential host rocks for the disposal of high-level nuclear waste due to their ability to limit radionuclide transport to molecular diffusion. Laboratory studies related to the investigation of radionuclide diffusion behavior are usually performed at relatively high concentrations. For instance, U diffusion in clay rocks has been investigated at concentrations as low as approximately 10<sup>–4</sup> mol·m<sup>–3</sup> clay. This study addresses <sup>233</sup>U(VI) diffusion in OPA down to ultratrace concentrations of 10<sup>–9</sup> mol·m<sup>–3</sup> using accelerator mass spectrometry. Fitting of the experimental data with a one-dimensional pore diffusion model revealed no significant changes in the U(VI) effective diffusion coefficient (<i>D</i><sub>e</sub>) over the investigated concentration range of 10<sup>–3</sup> to 10<sup>–9</sup> mol·m<sup>–3</sup>. Such concentration-independent behavior constitutes valuable information for the prediction of long-term U(VI) migration in geological repositories with OPA as host rock.","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":"17 1","pages":""},"PeriodicalIF":9.028,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143862480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tor Nordam, Anusha L. Dissanayake, Odd Gunnar Brakstad, Sigrid Hakvåg, Ida Beathe Øverjordet, Emma Litzler, Raymond Nepstad, Annika Drews, Johannes Röhrs
Methane is an important greenhouse gas, with a global warming potential that is far higher than that of CO2. Methane from seafloor seeps, whether naturally occurring or in relation to petroleum infrastructure, has been suggested to be a significant contribution to greenhouse gas releases. Here, we consider the fate of methane from seeps on the Norwegian continental shelf by means of models for dissolution of methane from rising bubbles, mixing and biodegradation of dissolved methane, and mass transfer to the atmosphere. Laboratory experiments with tritium-labeled methane have been conducted to help determine the biodegradation rate of methane in natural seawater, and the results, together with literature data, have been used to guide the modeling. From the modeling study, we present results as a function of biodegradation half-life, treating this as a free parameter to reflect the considerable span in values reported in the literature. Considering three different locations on the Norwegian continental shelf, we find that if the biodegradation half-life of methane is in the range of a 9 to 16 days, as suggested by our experiments, then about 57–68% of the released methane will biodegrade in the water column from a seep at 65 m depth. For deeper locations of 106 and 303 m, we find respectively 75–83%, and more than 99% biodegradation.
{"title":"Fate of Dissolved Methane from Ocean Floor Seeps","authors":"Tor Nordam, Anusha L. Dissanayake, Odd Gunnar Brakstad, Sigrid Hakvåg, Ida Beathe Øverjordet, Emma Litzler, Raymond Nepstad, Annika Drews, Johannes Röhrs","doi":"10.1021/acs.est.5c03297","DOIUrl":"https://doi.org/10.1021/acs.est.5c03297","url":null,"abstract":"Methane is an important greenhouse gas, with a global warming potential that is far higher than that of CO<sub>2</sub>. Methane from seafloor seeps, whether naturally occurring or in relation to petroleum infrastructure, has been suggested to be a significant contribution to greenhouse gas releases. Here, we consider the fate of methane from seeps on the Norwegian continental shelf by means of models for dissolution of methane from rising bubbles, mixing and biodegradation of dissolved methane, and mass transfer to the atmosphere. Laboratory experiments with tritium-labeled methane have been conducted to help determine the biodegradation rate of methane in natural seawater, and the results, together with literature data, have been used to guide the modeling. From the modeling study, we present results as a function of biodegradation half-life, treating this as a free parameter to reflect the considerable span in values reported in the literature. Considering three different locations on the Norwegian continental shelf, we find that if the biodegradation half-life of methane is in the range of a 9 to 16 days, as suggested by our experiments, then about 57–68% of the released methane will biodegrade in the water column from a seep at 65 m depth. For deeper locations of 106 and 303 m, we find respectively 75–83%, and more than 99% biodegradation.","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":"7 1","pages":""},"PeriodicalIF":9.028,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143862484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Canonical thermal cycloaromatizations (Bergman, C1–C6; Myers-Saito, C2–C7; Schmittel, C2–C6; Schreiner-Pascal, C1–C5) are limited to the formation of five- or six-membered rings, while the formation of larger rings from enediyne (or enyne-allenes) has no precedent experimental exploration. Herein, we present a novel thermal cyclization of enediyne, leading to the formation of a stable seven-membered cyclization product. The structure of this product was elucidated by using NMR and single-crystal X-ray diffraction techniques. The presence of a maleic hydrazide moiety is postulated to facilitate the proton transfer, resulting in the rearrangement of enediyne to enyne-allene, culminating in ring closure through Cα–C6 cyclization. The reaction mechanism was further explored by using density functional theory (DFT), revealing a low activation barrier for the Cα–C6 cyclization at 19.6 kcal/mol. The newly formed seven-membered ring exhibits strong Möbius aromaticity, as confirmed by calculations of the nucleus-independent chemical shift (NICS) and anisotropy of the induced current density (ACID). In the subsequent reaction, the fusion of the oxazolidin-2-one ring and the elimination of the isobutene molecule release a significant amount of energy, further driving the formation of the final product.
{"title":"Thermal Cα–C6 Cyclization of Enediynes","authors":"Haonan Cheng, Wenbo Wang, Yun Zeng, Houjun Zhang, Xiaohua Huang, Fangxu Pu, Xiaofan Zhang, Aiguo Hu, Yun Ding","doi":"10.1021/acs.joc.4c03124","DOIUrl":"https://doi.org/10.1021/acs.joc.4c03124","url":null,"abstract":"Canonical thermal cycloaromatizations (Bergman, C<sup>1</sup>–C<sup>6</sup>; Myers-Saito, C<sup>2</sup>–C<sup>7</sup>; Schmittel, C<sup>2</sup>–C<sup>6</sup>; Schreiner-Pascal, C<sup>1</sup>–C<sup>5</sup>) are limited to the formation of five- or six-membered rings, while the formation of larger rings from enediyne (or enyne-allenes) has no precedent experimental exploration. Herein, we present a novel thermal cyclization of enediyne, leading to the formation of a stable seven-membered cyclization product. The structure of this product was elucidated by using NMR and single-crystal X-ray diffraction techniques. The presence of a maleic hydrazide moiety is postulated to facilitate the proton transfer, resulting in the rearrangement of enediyne to enyne-allene, culminating in ring closure through C<sup>α</sup>–C<sup>6</sup> cyclization. The reaction mechanism was further explored by using density functional theory (DFT), revealing a low activation barrier for the C<sup>α</sup>–C<sup>6</sup> cyclization at 19.6 kcal/mol. The newly formed seven-membered ring exhibits strong Möbius aromaticity, as confirmed by calculations of the nucleus-independent chemical shift (NICS) and anisotropy of the induced current density (ACID). In the subsequent reaction, the fusion of the oxazolidin-2-one ring and the elimination of the isobutene molecule release a significant amount of energy, further driving the formation of the final product.","PeriodicalId":57,"journal":{"name":"Journal of Organic Chemistry","volume":"47 1","pages":""},"PeriodicalIF":4.354,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143858114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Child's play: The Front Cover shows how two flexible but robust metal–organic frameworks can easily be transformed into each other by the simple removal or adsorption of water molecules when immersed in this solvent. More information can be found in the Research Article by R. F. Mendes and F. A. Almeida Paz (DOI: 10.1002/ejic.202400467).
{"title":"Front Cover: Breathing Effect in a Tetrapodal Lanthanide-Phosphonate Organic Framework (Eur. J. Inorg. Chem. 12/2025)","authors":"Ricardo F. Mendes, Filipe A. Almeida Paz","doi":"10.1002/ejic.202581201","DOIUrl":"https://doi.org/10.1002/ejic.202581201","url":null,"abstract":"<p><b>Child's play</b>: The Front Cover shows how two flexible but robust metal–organic frameworks can easily be transformed into each other by the simple removal or adsorption of water molecules when immersed in this solvent. More information can be found in the Research Article by R. F. Mendes and F. A. Almeida Paz (DOI: 10.1002/ejic.202400467).\u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure>\u0000 </p>","PeriodicalId":38,"journal":{"name":"European Journal of Inorganic Chemistry","volume":"28 12","pages":""},"PeriodicalIF":2.2,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ejic.202581201","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143861641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shengbo Wang, Xiuli Hou, Yichan Li, Chen Zhou, Peng Zhang, Chun Hu
Developing efficient heterogeneous Fenton-like catalysts is the key point to accelerating the removal of organic micropollutants in the advanced oxidation process. However, a general principle guiding the reasonable design of highly efficient heterogeneous Fenton-like catalysts has not been constructed up to now. In this work, a total of 16 single-atom and 272 dual-atom transition metal/nitrogen/carbon (TM/N/C) catalysts for H2O2 dissociation were explored systematically based on high-throughput density functional theory and machine learning. It was found that H2O2 dissociation on single-atom TM/N/C exhibited a distinct volcano-type relationship between catalytic activity and •OH adsorption energy. The favorable •OH adsorption energies were in the range of −3.11 ∼ −2.20 eV. Three different descriptors, namely, energetic, electronic, and structural descriptors, were found, which can correlate the intrinsic properties of catalysts and their catalytic activity. Using adsorption energy, stability, and activation energy as the evaluation criteria, two dual-atom CoCu/N/C and CoRu/N/C catalysts were screened out from 272 candidates, which exhibited higher catalytic activity than the best single-atom TM/N/C catalyst due to the synergistic effect. This work could present a conceptually novel understanding of H2O2 dissociation on TM/N/C and inspire the structure-oriented catalyst design from the viewpoint of volcano relationship.
{"title":"From Single-Atom to Dual-Atom: A Universal Principle for the Rational Design of Heterogeneous Fenton-like Catalysts","authors":"Shengbo Wang, Xiuli Hou, Yichan Li, Chen Zhou, Peng Zhang, Chun Hu","doi":"10.1021/acs.est.4c13826","DOIUrl":"https://doi.org/10.1021/acs.est.4c13826","url":null,"abstract":"Developing efficient heterogeneous Fenton-like catalysts is the key point to accelerating the removal of organic micropollutants in the advanced oxidation process. However, a general principle guiding the reasonable design of highly efficient heterogeneous Fenton-like catalysts has not been constructed up to now. In this work, a total of 16 single-atom and 272 dual-atom transition metal/nitrogen/carbon (TM/N/C) catalysts for H<sub>2</sub>O<sub>2</sub> dissociation were explored systematically based on high-throughput density functional theory and machine learning. It was found that H<sub>2</sub>O<sub>2</sub> dissociation on single-atom TM/N/C exhibited a distinct volcano-type relationship between catalytic activity and <sup>•</sup>OH adsorption energy. The favorable <sup>•</sup>OH adsorption energies were in the range of −3.11 ∼ −2.20 eV. Three different descriptors, namely, energetic, electronic, and structural descriptors, were found, which can correlate the intrinsic properties of catalysts and their catalytic activity. Using adsorption energy, stability, and activation energy as the evaluation criteria, two dual-atom CoCu/N/C and CoRu/N/C catalysts were screened out from 272 candidates, which exhibited higher catalytic activity than the best single-atom TM/N/C catalyst due to the synergistic effect. This work could present a conceptually novel understanding of H<sub>2</sub>O<sub>2</sub> dissociation on TM/N/C and inspire the structure-oriented catalyst design from the viewpoint of volcano relationship.","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":"7 1","pages":""},"PeriodicalIF":9.028,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143857687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Microplastic bioaccumulation (MPB) within marine fish through the food chain has been extensively validated in traditional experimental studies. However, the idealized conditions of these studies fail to fully capture the complex, nonlinear interactions among marine microplastics, biota, and environmental factors in real-world scenarios, and the spatiotemporal characteristics of risks are lacking in these studies, hindering the accurate assessment and control of risk. To address the above knowledge gaps, we constructed an improved sparrow search algorithm/geographic random forest (ISSA–GRF) conceptual framework and analyzed MPB in 82 common fish species from coastal ecosystems. The rate of MPB in coastal fish in 22 major marine ecosystems has increased by an average of 3.56% over the past decade. Hotspot areas such as the Red Sea coast, Gulf of Thailand coast, and Sulawesi Sea coast were identified; the bioaccumulation rates increased by 8.00%, 5.68%, and 5.34%, respectively. Ocean eutrophication, triggered by changes in nutrient levels, was revealed as the main driver via a causal analysis. These findings not only independently validate the increasing risk of microplastic biological accumulation outside the laboratory environment but also highlight the importance of controlling marine eutrophication to mitigate the biological risks associated with microplastics.
{"title":"Eutrophication Exacerbates Microplastic Bioaccumulation Risks in Coastal Fish","authors":"Chunhui Liu, Xiangang Hu, Can Shen, Zhangjia Wang","doi":"10.1021/acs.est.4c14498","DOIUrl":"https://doi.org/10.1021/acs.est.4c14498","url":null,"abstract":"Microplastic bioaccumulation (MPB) within marine fish through the food chain has been extensively validated in traditional experimental studies. However, the idealized conditions of these studies fail to fully capture the complex, nonlinear interactions among marine microplastics, biota, and environmental factors in real-world scenarios, and the spatiotemporal characteristics of risks are lacking in these studies, hindering the accurate assessment and control of risk. To address the above knowledge gaps, we constructed an improved sparrow search algorithm/geographic random forest (ISSA–GRF) conceptual framework and analyzed MPB in 82 common fish species from coastal ecosystems. The rate of MPB in coastal fish in 22 major marine ecosystems has increased by an average of 3.56% over the past decade. Hotspot areas such as the Red Sea coast, Gulf of Thailand coast, and Sulawesi Sea coast were identified; the bioaccumulation rates increased by 8.00%, 5.68%, and 5.34%, respectively. Ocean eutrophication, triggered by changes in nutrient levels, was revealed as the main driver via a causal analysis. These findings not only independently validate the increasing risk of microplastic biological accumulation outside the laboratory environment but also highlight the importance of controlling marine eutrophication to mitigate the biological risks associated with microplastics.","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":"129 1","pages":""},"PeriodicalIF":9.028,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143857688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-04-22DOI: 10.1021/acs.jpcc.5c00855
Tarik Ouahrani, A. Esquembre Kučukalić, R. M. Boufatah, Daniel Errandonea
The binding energy of excitons is essential in assessing the suitability of materials for photovoltaic applications. This research employs first-principles calculations based on the GW approximation and the Bethe–Salpeter equation to explore the excitonic characteristics of a Cu2WSe4 monolayer. Our findings support the structural stability of this two-dimensional material and demonstrate a pronounced excitonic response. The computed binding energies for both bright and dark excitons are considerably larger than those that are generally necessary for standard photovoltaic applications. However, examination of exciton amplitude reveals a highly delocalized configuration of electron–hole pairs throughout the crystal, which may alleviate some issues related to elevated binding energies. These results highlight the excitonic properties of Cu2WSe4 and offer valuable insights into its potential for optoelectronic applications.
{"title":"Optical Properties of Single Layer Cu2WSe4 from the Ab Initio Bethe–Salpeter Equation Method","authors":"Tarik Ouahrani, A. Esquembre Kučukalić, R. M. Boufatah, Daniel Errandonea","doi":"10.1021/acs.jpcc.5c00855","DOIUrl":"https://doi.org/10.1021/acs.jpcc.5c00855","url":null,"abstract":"The binding energy of excitons is essential in assessing the suitability of materials for photovoltaic applications. This research employs first-principles calculations based on the <i>GW</i> approximation and the Bethe–Salpeter equation to explore the excitonic characteristics of a Cu<sub>2</sub>WSe<sub>4</sub> monolayer. Our findings support the structural stability of this two-dimensional material and demonstrate a pronounced excitonic response. The computed binding energies for both bright and dark excitons are considerably larger than those that are generally necessary for standard photovoltaic applications. However, examination of exciton amplitude reveals a highly delocalized configuration of electron–hole pairs throughout the crystal, which may alleviate some issues related to elevated binding energies. These results highlight the excitonic properties of Cu<sub>2</sub>WSe<sub>4</sub> and offer valuable insights into its potential for optoelectronic applications.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"62 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143858235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Qi Song, Yu Hua, Shuxian Chen, Xiaoguang Liu, Xiaohu Dai
To destabilize the microstructure resulting from microorganism physiology and substance combination in waste-activated sludge (WAS), this study proposes a novel approach by employing nonionic surfactants for pretreatment with a specific focus on alkyl polyglucosides (APG). Inspired by the enhanced dispersibility and targeted hydrophobic interactions of surfactants at low doses, this approach strategically applies APG pretreatment at 0.05 and 0.10 g/g TS, which boosted biogas production by 49.7 and 62.9%, respectively, compared to the control group. The analysis showed that the assembly of APG hydrophobic functional groups with hydrophobic functional groups in EPS enhanced the surface free energy of sludge particles and led to the evacuation of TB-EPS. Microbial diversity analysis reveals shifts in bacteria and archaea in response to APG pretreatment, significant as bacteria Azonexus, Syntrophomonas, Lutispora, and archaea Methanosarcina emerge as new dominant genera. When adding a low dose of APG (<0.10 g/g TS), the destabilization of sludge microstructure (weakening nonfunctional binding between sludge particles and biological enzymes) led to a significant increase in the freedom and activity of enzymes involved in methane metabolism pathways. This study can provide valuable insights for surface interface regulation and efficient biomass energy recovery of complex organic waste.
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