Pub Date : 2024-09-28DOI: 10.1016/j.partic.2024.09.015
Yuhua Zhang , Yanmei Jin , Song Li , Hong Wu , Huijuan Luo
In this study, high-performance porous carbon for CO2 adsorption was synthesized from pistachio shells and modified with urea to enrich nitrogen content in the porous structure. The effects of activation temperature, KOH-to-carbon ratio, and urea addition on the pore structure and CO2 adsorption capacity of the porous carbon were investigated. Characterization was conducted using N2 adsorption-desorption isotherms, scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy (FT-IR). Results showed that under preparation conditions of 700 °C, KOH-to-carbon ratio of 2, and 15 wt% urea concentration, the synthesized GAC-15-2-700 porous carbon exhibited a maximum specific surface area of 1395 m2/g, micropore volume of 0.505 cm3/g, and N-5 peak area ratio of 65.57%. It achieved a CO2 adsorption capacity of 3.56 mmol/g. Nitrogen functional groups on the porous carbon primarily existed as pyridinic N (N-6), pyrrolic/pyridinic N (N-5), and quaternary N (N-Q), with the enriched micropores and high N-5 content being crucial for CO2 adsorption.
{"title":"Preparation of pistachio shell-based porous carbon and its adsorption performance for low concentration CO2","authors":"Yuhua Zhang , Yanmei Jin , Song Li , Hong Wu , Huijuan Luo","doi":"10.1016/j.partic.2024.09.015","DOIUrl":"10.1016/j.partic.2024.09.015","url":null,"abstract":"<div><div>In this study, high-performance porous carbon for CO<sub>2</sub> adsorption was synthesized from pistachio shells and modified with urea to enrich nitrogen content in the porous structure. The effects of activation temperature, KOH-to-carbon ratio, and urea addition on the pore structure and CO<sub>2</sub> adsorption capacity of the porous carbon were investigated. Characterization was conducted using N<sub>2</sub> adsorption-desorption isotherms, scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy (FT-IR). Results showed that under preparation conditions of 700 °C, KOH-to-carbon ratio of 2, and 15 wt% urea concentration, the synthesized GAC-15-2-700 porous carbon exhibited a maximum specific surface area of 1395 m<sup>2</sup>/g, micropore volume of 0.505 cm<sup>3</sup>/g, and N-5 peak area ratio of 65.57%. It achieved a CO<sub>2</sub> adsorption capacity of 3.56 mmol/g. Nitrogen functional groups on the porous carbon primarily existed as pyridinic N (N-6), pyrrolic/pyridinic N (N-5), and quaternary N (N-Q), with the enriched micropores and high N-5 content being crucial for CO<sub>2</sub> adsorption.</div></div>","PeriodicalId":401,"journal":{"name":"Particuology","volume":"95 ","pages":"Pages 103-114"},"PeriodicalIF":4.1,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-28DOI: 10.1016/j.partic.2024.09.012
Minghua Wang , Liuyong Chang , Xuehuan Hu , Meiyin Zhu , Bin Zhang , Guangze Li , Zheng Xu
The precise measurement of non-volatile Particulate Matter (nvPM) is outlined in aviation engine emissions regulations by the International Civil Aviation Organization (ICAO). However, assessing particle losses in the sampling and transfer unit presents challenges, raising concerns about the system's reliability. Moreover, nvPM emissions from small and medium aircraft engines, with thrust not exceeding 26.7 kN, vary widely in size, adding complexity to the measurement process. To provide a comprehensive analysis of particle losses in the sampling and transfer subsystems, this study established a test bench equipped with a nanoparticle generator. The generator simulates nvPM emissions from medium and small aircraft engines and can consistently produce nvPMs with a wide range of concentrations (10³-10⁷/cm³) and size distributions (20–160 nm). Thermophoretic loss verification experiments were conducted within the sampling pipeline under significant temperature differences, investigating the effects of particle size, temperature gradient, and airflow rate on thermophoretic particle losses. The experimental results demonstrated good agreement with the predictions of the model proposed by United Technologies Research Centre (UTRC). After correcting for temperature, the experimental data showed a maximum disparity of 2% under typical engine exhaust conditions, validating the predictability of the thermophoretic loss model for various engine types. Furthermore, verification experiments for particle diffusion and bending losses were performed. Comparative analysis with the UTRC model revealed nvPM inertial deposition under laminar flow conditions with low Reynolds numbers (Re). As the Re increased, the measured data more closely aligned with the simulations. Bending losses due to secondary flow patterns ranged from 1% to 10%, depending on particle size and flow rate. This finding supports the applicability of aviation nvPM measurement methods across a wide particle size range. This research provides theoretical support for future nvPM measurements on various aircraft engines, laying the groundwork for improved accuracy and reliability in emissions monitoring.
{"title":"Investigation on the particle loss and applicability of aviation nvPM measurement methodology for wide particle size ranges","authors":"Minghua Wang , Liuyong Chang , Xuehuan Hu , Meiyin Zhu , Bin Zhang , Guangze Li , Zheng Xu","doi":"10.1016/j.partic.2024.09.012","DOIUrl":"10.1016/j.partic.2024.09.012","url":null,"abstract":"<div><div>The precise measurement of non-volatile Particulate Matter (nvPM) is outlined in aviation engine emissions regulations by the International Civil Aviation Organization (ICAO). However, assessing particle losses in the sampling and transfer unit presents challenges, raising concerns about the system's reliability. Moreover, nvPM emissions from small and medium aircraft engines, with thrust not exceeding 26.7 kN, vary widely in size, adding complexity to the measurement process. To provide a comprehensive analysis of particle losses in the sampling and transfer subsystems, this study established a test bench equipped with a nanoparticle generator. The generator simulates nvPM emissions from medium and small aircraft engines and can consistently produce nvPMs with a wide range of concentrations (10³-10⁷/cm³) and size distributions (20–160 nm). Thermophoretic loss verification experiments were conducted within the sampling pipeline under significant temperature differences, investigating the effects of particle size, temperature gradient, and airflow rate on thermophoretic particle losses. The experimental results demonstrated good agreement with the predictions of the model proposed by United Technologies Research Centre (UTRC). After correcting for temperature, the experimental data showed a maximum disparity of 2% under typical engine exhaust conditions, validating the predictability of the thermophoretic loss model for various engine types. Furthermore, verification experiments for particle diffusion and bending losses were performed. Comparative analysis with the UTRC model revealed nvPM inertial deposition under laminar flow conditions with low Reynolds numbers (Re). As the Re increased, the measured data more closely aligned with the simulations. Bending losses due to secondary flow patterns ranged from 1% to 10%, depending on particle size and flow rate. This finding supports the applicability of aviation nvPM measurement methods across a wide particle size range. This research provides theoretical support for future nvPM measurements on various aircraft engines, laying the groundwork for improved accuracy and reliability in emissions monitoring.</div></div>","PeriodicalId":401,"journal":{"name":"Particuology","volume":"95 ","pages":"Pages 154-165"},"PeriodicalIF":4.1,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142432302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-27DOI: 10.1016/j.partic.2024.09.008
Jingrui Cao , Shibo Wu , Jiahao He , Yang Zhou , Pianpian Ma
To address the global challenges associated with energy and environmental concerns, the design, development, and application of novel materials have emerged as pivotal drivers. Notably, high-entropy perovskite oxides (HEPOs) amalgamate the merits of both perovskite oxides and high-entropy materials, presenting significant potential in addressing numerous critical issues in energy and environment. This review delves into the recent advancements of HEPOs in these domains. Firstly, it provides an overview of prevalent synthesis techniques for HEPOs, alongside two emerging low-temperature, eco-friendly methods. Subsequently, current strategies to optimize the performance of HEPOs are summarized from three perspectives: compositional engineering, morphological engineering, and structural engineering. The review further underscores their applications in areas such as lithium-ion batteries, supercapacitors, electrocatalysts, and solid oxide fuel cells. Based on this foundation, potential performance optimization strategies and potential application areas of HEPOs are discussed. Finally, it identifies challenges faced by further development of HEPOs in energy and environmental applications and provides an outlook on future developments.
{"title":"Research progress of high-entropy perovskite oxides in energy and environmental applications: A review","authors":"Jingrui Cao , Shibo Wu , Jiahao He , Yang Zhou , Pianpian Ma","doi":"10.1016/j.partic.2024.09.008","DOIUrl":"10.1016/j.partic.2024.09.008","url":null,"abstract":"<div><div>To address the global challenges associated with energy and environmental concerns, the design, development, and application of novel materials have emerged as pivotal drivers. Notably, high-entropy perovskite oxides (HEPOs) amalgamate the merits of both perovskite oxides and high-entropy materials, presenting significant potential in addressing numerous critical issues in energy and environment. This review delves into the recent advancements of HEPOs in these domains. Firstly, it provides an overview of prevalent synthesis techniques for HEPOs, alongside two emerging low-temperature, eco-friendly methods. Subsequently, current strategies to optimize the performance of HEPOs are summarized from three perspectives: compositional engineering, morphological engineering, and structural engineering. The review further underscores their applications in areas such as lithium-ion batteries, supercapacitors, electrocatalysts, and solid oxide fuel cells. Based on this foundation, potential performance optimization strategies and potential application areas of HEPOs are discussed. Finally, it identifies challenges faced by further development of HEPOs in energy and environmental applications and provides an outlook on future developments.</div></div>","PeriodicalId":401,"journal":{"name":"Particuology","volume":"95 ","pages":"Pages 62-81"},"PeriodicalIF":4.1,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-26DOI: 10.1016/j.partic.2024.09.013
Cong Leng, Chengfeng Sun, Zhehan Liao, Jian Xu
Granular size segregation is an inevitable phenomenon in both natural and industrial processes. To understand the underlying mechanisms and develop effective optimization strategies, it is essential to employ robust methodologies that can quantitatively characterize and evaluate size segregation behaviors in granular systems. This review critically examines a wide variety of state-of-the-art methodologies from recent studies to quantify granular size segregation. The features of these methodologies are extracted and organized into a comprehensive framework. Four key questions are thoroughly discussed: evaluation criteria for identical segregation states, sensitivity to sample size, the influence of sampling division pattern, and the capability of handling multiple-component system. Finally, we provide an outlook on the future development of advanced and effective methodologies for granular size segregation characterization.
{"title":"Quantitative characterization of granular size segregation: A critical review","authors":"Cong Leng, Chengfeng Sun, Zhehan Liao, Jian Xu","doi":"10.1016/j.partic.2024.09.013","DOIUrl":"10.1016/j.partic.2024.09.013","url":null,"abstract":"<div><div>Granular size segregation is an inevitable phenomenon in both natural and industrial processes. To understand the underlying mechanisms and develop effective optimization strategies, it is essential to employ robust methodologies that can quantitatively characterize and evaluate size segregation behaviors in granular systems. This review critically examines a wide variety of state-of-the-art methodologies from recent studies to quantify granular size segregation. The features of these methodologies are extracted and organized into a comprehensive framework. Four key questions are thoroughly discussed: evaluation criteria for identical segregation states, sensitivity to sample size, the influence of sampling division pattern, and the capability of handling multiple-component system. Finally, we provide an outlook on the future development of advanced and effective methodologies for granular size segregation characterization.</div></div>","PeriodicalId":401,"journal":{"name":"Particuology","volume":"95 ","pages":"Pages 166-177"},"PeriodicalIF":4.1,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142442120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-26DOI: 10.1016/j.partic.2024.09.014
Renbo Deng , Shiran Li , Qianqian Wang , Jiaying Liang , Xufeng Zang , Huiling Xia
Although a few studies reveal the reasons of poor charge-discharge abilities for lithium-ion batteries based on LiNixMnyCo1-x-yO2 at low temperature, there are still some practical issues worthy of further investigation. For instance, how the side reactions affect the cyclabilities of commercial LiCoO2/artificial graphite (LCO/AG) cells at different low temperatures, and are the synergistic effects between the side reactions similar to that at room temperature? To answer the issues, the performances of a ⁓3 Ah LCO/AG pouch cell at different temperatures and C-rates are studied. Results illustrate that the obvious increase in charge transferring impedance especially in AG anode at low temperature causes large polarization, then reducing charge-discharge ability and even yielding lithium deposition at −10 °C and 0.5C under 3−4.45 V. Different from at room temperature, the side reactions such as electrolyte decomposition and electrode structural evolution reduce significantly at low temperature, which contribute to an excellent cyclability after 500 cycles at 0 °C. Instead, a series of chain reactions cause a relative lower cyclability at 25 °C. Lithium deposition is slight after 5 cycles at −10 °C, but become considerably severe after 20 cycles and cause rollover failure of capacity. All these results deepen the understanding on mechanisms for different behaviors of LCO/AG cells at low temperature and provide optimization direction.
尽管一些研究揭示了基于镍钴锰酸锂-x-二氧化钛的锂离子电池在低温下充放电能力差的原因，但仍有一些实际问题值得进一步研究。例如，副反应如何影响商用钴酸锂/人造石墨（LCO/AG）电池在不同低温下的循环能力？为了回答这些问题，我们研究了⁓3 Ah LCO/AG 袋式电池在不同温度和 C 率下的性能。结果表明，在-10 °C和0.5 °C、3-4.45 V电压条件下，低温下电荷转移阻抗（尤其是 AG 阳极）明显增加，导致极化较大，进而降低充放电能力，甚至产生锂沉积。与室温下不同的是，低温下电解质分解和电极结构演变等副反应显著减少，这有助于在 0 °C 下循环 500 次后获得极佳的循环能力。相反，在 25 °C时，一系列连锁反应导致循环能力相对较低。在-10 °C下循环 5 次后，锂沉积轻微，但循环 20 次后，锂沉积变得相当严重，并导致容量翻转失效。所有这些结果加深了人们对 LCO/AG 电池在低温下的不同行为机理的理解，并为优化提供了方向。
{"title":"Mechanisms for different cyclabilities of commercial LiCoO2/artificial graphite pouch cells at −10, 0, and 25 °C","authors":"Renbo Deng , Shiran Li , Qianqian Wang , Jiaying Liang , Xufeng Zang , Huiling Xia","doi":"10.1016/j.partic.2024.09.014","DOIUrl":"10.1016/j.partic.2024.09.014","url":null,"abstract":"<div><div>Although a few studies reveal the reasons of poor charge-discharge abilities for lithium-ion batteries based on LiNi<sub>x</sub>Mn<sub>y</sub>Co<sub>1-x-y</sub>O<sub>2</sub> at low temperature, there are still some practical issues worthy of further investigation. For instance, how the side reactions affect the cyclabilities of commercial LiCoO<sub>2</sub>/artificial graphite (LCO/AG) cells at different low temperatures, and are the synergistic effects between the side reactions similar to that at room temperature? To answer the issues, the performances of a ⁓3 Ah LCO/AG pouch cell at different temperatures and C-rates are studied. Results illustrate that the obvious increase in charge transferring impedance especially in AG anode at low temperature causes large polarization, then reducing charge-discharge ability and even yielding lithium deposition at −10 °C and 0.5C under 3−4.45 V. Different from at room temperature, the side reactions such as electrolyte decomposition and electrode structural evolution reduce significantly at low temperature, which contribute to an excellent cyclability after 500 cycles at 0 °C. Instead, a series of chain reactions cause a relative lower cyclability at 25 °C. Lithium deposition is slight after 5 cycles at −10 °C, but become considerably severe after 20 cycles and cause rollover failure of capacity. All these results deepen the understanding on mechanisms for different behaviors of LCO/AG cells at low temperature and provide optimization direction.</div></div>","PeriodicalId":401,"journal":{"name":"Particuology","volume":"95 ","pages":"Pages 145-153"},"PeriodicalIF":4.1,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-25DOI: 10.1016/j.partic.2024.09.011
Jiangkai Ma , Jingjing Meng , Yanhui Wang , Xuan Liu , Xiaoting Zhang , Kaiyue Yang , Qiang Liu , Zhanfang Hou
Oxalic acid (C2) is a significant tracer of secondary organic aerosols (SOA), yet its precursors, evolutionary processes, and formation mechanisms are not fully understood. This knowledge gap leads to uncertainties in evaluating the climate effect and global budget of SOA. Here we compared the size distribution, mixing fraction, and evolutionary mechanism of C2-containing particles between summer and winter. In summer, the number of C2 particles and their homologs decreased compared to winter. However, the proportion of C2 relative to the total number of determined particles increased, indicating that the summertime particles are more aged. Higher relative aerosol acidity (Rra) and lower in-situ pH (pHis) in summer suggest that particles are more acidic during this season. Correlation analysis and temporal variation characteristics suggest that from 9: 00 to 15: 00 in summer, C2 particles mostly originate from the photochemical decomposition of larger dicarboxylic aids, driven by O3 concentration. Conversely, from 16: 00 to 20: 00, C2 particles are predominantly formed through aqueous-phase oxidation, influenced by higher relative humidity (RH), aerosol liquid water content (ALWC), and acidity. Additionally, heavy metal particles were the predominant type of C2 particles, and C2 particles exhibited an opposite diurnal variation to Fe in summer, suggesting that the photolysis of iron oxalate complexes is an important sink of C2 particles during this period. In winter, biomass burning (BB) particles were the most abundant, and a robust correlation between levoglucosan and C2 particles indicated a substantial influence of BB on C2 particles. The aqueous generation of C2 particles from α-dicarbonyls driven by acidity was most effective when RH varied from 40% to 60% in the wintertime state of particles. These findings highlight the hourly and seasonal variations in the sources and evolutionary processes of SOA. Such variations must be considered in developing control measures and simulating the climate effect of SOA.
{"title":"Mixing state and evolutionary mechanism of oxalic acid homologs in Liaocheng, East China: Insights from seasonal and hourly observations","authors":"Jiangkai Ma , Jingjing Meng , Yanhui Wang , Xuan Liu , Xiaoting Zhang , Kaiyue Yang , Qiang Liu , Zhanfang Hou","doi":"10.1016/j.partic.2024.09.011","DOIUrl":"10.1016/j.partic.2024.09.011","url":null,"abstract":"<div><div>Oxalic acid (C<sub>2</sub>) is a significant tracer of secondary organic aerosols (SOA), yet its precursors, evolutionary processes, and formation mechanisms are not fully understood. This knowledge gap leads to uncertainties in evaluating the climate effect and global budget of SOA. Here we compared the size distribution, mixing fraction, and evolutionary mechanism of C<sub>2</sub>-containing particles between summer and winter. In summer, the number of C<sub>2</sub> particles and their homologs decreased compared to winter. However, the proportion of C<sub>2</sub> relative to the total number of determined particles increased, indicating that the summertime particles are more aged. Higher relative aerosol acidity (R<sub>ra</sub>) and lower in-situ pH (pH<sub>is</sub>) in summer suggest that particles are more acidic during this season. Correlation analysis and temporal variation characteristics suggest that from 9: 00 to 15: 00 in summer, C<sub>2</sub> particles mostly originate from the photochemical decomposition of larger dicarboxylic aids, driven by O<sub>3</sub> concentration. Conversely, from 16: 00 to 20: 00, C<sub>2</sub> particles are predominantly formed through aqueous-phase oxidation, influenced by higher relative humidity (RH), aerosol liquid water content (ALWC), and acidity. Additionally, heavy metal particles were the predominant type of C<sub>2</sub> particles, and C<sub>2</sub> particles exhibited an opposite diurnal variation to Fe in summer, suggesting that the photolysis of iron oxalate complexes is an important sink of C<sub>2</sub> particles during this period. In winter, biomass burning (BB) particles were the most abundant, and a robust correlation between levoglucosan and C<sub>2</sub> particles indicated a substantial influence of BB on C<sub>2</sub> particles. The aqueous generation of C<sub>2</sub> particles from α-dicarbonyls driven by acidity was most effective when RH varied from 40% to 60% in the wintertime state of particles. These findings highlight the hourly and seasonal variations in the sources and evolutionary processes of SOA. Such variations must be considered in developing control measures and simulating the climate effect of SOA.</div></div>","PeriodicalId":401,"journal":{"name":"Particuology","volume":"95 ","pages":"Pages 223-234"},"PeriodicalIF":4.1,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142528878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-24DOI: 10.1016/j.partic.2024.09.009
Xiaoqian Sun , Yunhui Du , Weiyi Zhang , Mengjiao Jin , Ruiang Fan , Peng Zhang
Lithium-rich manganese-based (Li-rich Mn-based) cathode materials possess high specific capacity, low self-discharge rate and steady working voltage, but cycle performance and rate performance need to be further improved. In this study, cathode materials Li1.2Mn0.54Ni0.13Co0.13O2-xFx (x = 0, 0.02, 0.05, 0.08) are synthesized by the co-precipitation method with the two-step calcination process. And the F-doping effects on the microstructure and the electrochemical performance are investigated in the cathode materials Li1.2Mn0.54Ni0.13Co0.13O2. The results indicate that among all the F-doped cathode materials, the crystal lattice parameters are increased, order degree and stability of the layered structure are improved. As for x = 0.05, cathode material Li1.2Mn0.54Ni0.13Co0.13O1.95F0.05 (LMO-F0.05) shows the best cycle performance and rate performance with its capacity retention rate 87.7% after 100 cycles at 0.2 C and discharge capacity 117 mAh g−1 at 5 C high power. It can be seen that F doping is a simple and crucial strategy to promote the Li ion diffusion and develop high performance layered cathode materials.
富锂锰基（Li-rich Mn-based）正极材料具有高比容量、低自放电率和稳定的工作电压，但循环性能和速率性能有待进一步提高。本研究采用共沉淀法和两步煅烧法合成了 Li1.2Mn0.54Ni0.13Co0.13O2-xFx (x = 0, 0.02, 0.05, 0.08) 阴极材料。研究了掺杂 F 对正极材料 Li1.2Mn0.54Ni0.13Co0.13O2 的微观结构和电化学性能的影响。结果表明，在所有掺杂 F 的阴极材料中，晶格参数都得到了提高，层状结构的有序度和稳定性也得到了改善。当 x = 0.05 时，阴极材料 Li1.2Mn0.54Ni0.13Co0.13O1.95F0.05 （LMO-F0.05）的循环性能和速率性能最好，在 0.2 C 下循环 100 次后容量保持率为 87.7%，在 5 C 大功率下放电容量为 117 mAh g-1。由此可见，掺杂 F 是促进锂离子扩散和开发高性能层状阴极材料的一种简单而关键的策略。
{"title":"F-doping effects on microstructure and electrochemical performance of cathode material Li1.2Mn0.54Ni0.13Co0.13O2","authors":"Xiaoqian Sun , Yunhui Du , Weiyi Zhang , Mengjiao Jin , Ruiang Fan , Peng Zhang","doi":"10.1016/j.partic.2024.09.009","DOIUrl":"10.1016/j.partic.2024.09.009","url":null,"abstract":"<div><div>Lithium-rich manganese-based (Li-rich Mn-based) cathode materials possess high specific capacity, low self-discharge rate and steady working voltage, but cycle performance and rate performance need to be further improved. In this study, cathode materials Li<sub>1.2</sub>Mn<sub>0.54</sub>Ni<sub>0.13</sub>Co<sub>0.13</sub>O<sub>2-x</sub>F<sub>x</sub> (x = 0, 0.02, 0.05, 0.08) are synthesized by the co-precipitation method with the two-step calcination process. And the F-doping effects on the microstructure and the electrochemical performance are investigated in the cathode materials Li<sub>1.2</sub>Mn<sub>0.54</sub>Ni<sub>0.13</sub>Co<sub>0.13</sub>O<sub>2</sub>. The results indicate that among all the F-doped cathode materials, the crystal lattice parameters are increased, order degree and stability of the layered structure are improved. As for x = 0.05, cathode material Li<sub>1.2</sub>Mn<sub>0.54</sub>Ni<sub>0.13</sub>Co<sub>0.13</sub>O<sub>1.95</sub>F<sub>0.05</sub> (LMO-F<sub>0.05</sub>) shows the best cycle performance and rate performance with its capacity retention rate 87.7% after 100 cycles at 0.2 C and discharge capacity 117 mAh g<sup>−1</sup> at 5 C high power. It can be seen that F doping is a simple and crucial strategy to promote the Li ion diffusion and develop high performance layered cathode materials.</div></div>","PeriodicalId":401,"journal":{"name":"Particuology","volume":"95 ","pages":"Pages 82-91"},"PeriodicalIF":4.1,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-24DOI: 10.1016/j.partic.2024.09.010
Bojian Qi , Yong Yan , Wenbiao Zhang
Flow dynamics of binary particles are investigated to realize the monitoring and optimization of fluidized beds. It is a challenge to accurately classify the mass fraction of mixed biomass, considering the limitations of existing techniques. The data collected from an electrostatic sensor array is analyzed. Cross correlation, empirical mode decomposition (EMD), Hilbert-Huang transform (HHT) are applied to process the signals. Under a higher mass fraction of the wood sawdust, the segregation behavior occurs, and the high energy region of HHT spectrum increases. Furthermore, two data-driven models are trained based on a hybrid wavelet scattering transform and bidirectional long short-term memory (ST-BiLSTM) network and a EMD and BiLSTM (EMD-BiLSTM) network to identify the mass fractions of the mixed biomass, with accuracies of 92% and 99%. The electrostatic sensing combined with the EMD-BiLSTM model is effective to classify the mass fraction of the mixed biomass.
{"title":"Investigations into the flow dynamics of mixed biomass particles in a fluidized bed through Hilbert-Huang transformation and data-driven modelling","authors":"Bojian Qi , Yong Yan , Wenbiao Zhang","doi":"10.1016/j.partic.2024.09.010","DOIUrl":"10.1016/j.partic.2024.09.010","url":null,"abstract":"<div><div>Flow dynamics of binary particles are investigated to realize the monitoring and optimization of fluidized beds. It is a challenge to accurately classify the mass fraction of mixed biomass, considering the limitations of existing techniques. The data collected from an electrostatic sensor array is analyzed. Cross correlation, empirical mode decomposition (EMD), Hilbert-Huang transform (HHT) are applied to process the signals. Under a higher mass fraction of the wood sawdust, the segregation behavior occurs, and the high energy region of HHT spectrum increases. Furthermore, two data-driven models are trained based on a hybrid wavelet scattering transform and bidirectional long short-term memory (ST-BiLSTM) network and a EMD and BiLSTM (EMD-BiLSTM) network to identify the mass fractions of the mixed biomass, with accuracies of 92% and 99%. The electrostatic sensing combined with the EMD-BiLSTM model is effective to classify the mass fraction of the mixed biomass.</div></div>","PeriodicalId":401,"journal":{"name":"Particuology","volume":"95 ","pages":"Pages 115-123"},"PeriodicalIF":4.1,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-21DOI: 10.1016/j.partic.2024.09.006
Chenglong Jiang , Yajing Liu , Lingling Zeng , Chengshun Xu , Peng Cao
An explanation of the meso-mechanism of sand granular materials for the uniqueness of critical state is presented by means of the discrete element method (DEM) under flexible boundary loading conditions. A series triaxial drainage shear test (DEM simulations), in conjunction with the flexible boundary technique, of were performed for sand samples subjected to various physical states and with different particle size distributions. After carefully investigating the critical status of the results of the numerical calculation, the macroscopic failure modes and shear band evolution of sand, as well as the velocity vector field due to different initial states, were explored and classified. Furthermore, the evaluation rules and discrepancies between overall void ratios of the specimen and local void ratios within the shear band under the critical state were recorded and analyzed. The results proved that a sample with a small void tends to form a shear band, and the rotation of the particles in the non-shear zone is negligible. Conversely, sandy soil with large initial void ratios exhibited limited development of significant shear bands, and the change in void ratios within the shear region and the non-shear area are not significant. Interestingly, the particle-size distribution exerts minimal influence on the evolution rule which the void ratio converges within the shear band and diverges outside the shear region for both multi-stage and single-stage specimens. The void ratio within the shear band and deviator stress ratio tend to exhibit consistently for the same specimen with different initial physical states, thereby distinguishing the critical state. There is a significantly higher change in void ratio within the shear band compared to outside of it, yet it remains stable within a relatively similar range. Additionally, the invariant of the fabric tensor used to describe the critical state characteristics also demonstrates a high degree of consistency within the shear band. These findings strongly indicate that the critical state exists within the shear failure surface and is highly likely to be unique.
{"title":"Critical state uniqueness of dense granular materials using discrete element method in conjunction with flexible membrane boundary","authors":"Chenglong Jiang , Yajing Liu , Lingling Zeng , Chengshun Xu , Peng Cao","doi":"10.1016/j.partic.2024.09.006","DOIUrl":"10.1016/j.partic.2024.09.006","url":null,"abstract":"<div><div>An explanation of the meso-mechanism of sand granular materials for the uniqueness of critical state is presented by means of the discrete element method (DEM) under flexible boundary loading conditions. A series triaxial drainage shear test (DEM simulations), in conjunction with the flexible boundary technique, of were performed for sand samples subjected to various physical states and with different particle size distributions. After carefully investigating the critical status of the results of the numerical calculation, the macroscopic failure modes and shear band evolution of sand, as well as the velocity vector field due to different initial states, were explored and classified. Furthermore, the evaluation rules and discrepancies between overall void ratios of the specimen and local void ratios within the shear band under the critical state were recorded and analyzed. The results proved that a sample with a small void tends to form a shear band, and the rotation of the particles in the non-shear zone is negligible. Conversely, sandy soil with large initial void ratios exhibited limited development of significant shear bands, and the change in void ratios within the shear region and the non-shear area are not significant. Interestingly, the particle-size distribution exerts minimal influence on the evolution rule which the void ratio converges within the shear band and diverges outside the shear region for both multi-stage and single-stage specimens. The void ratio within the shear band and deviator stress ratio tend to exhibit consistently for the same specimen with different initial physical states, thereby distinguishing the critical state. There is a significantly higher change in void ratio within the shear band compared to outside of it, yet it remains stable within a relatively similar range. Additionally, the invariant of the fabric tensor used to describe the critical state characteristics also demonstrates a high degree of consistency within the shear band. These findings strongly indicate that the critical state exists within the shear failure surface and is highly likely to be unique.</div></div>","PeriodicalId":401,"journal":{"name":"Particuology","volume":"95 ","pages":"Pages 124-144"},"PeriodicalIF":4.1,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-21DOI: 10.1016/j.partic.2024.09.007
Weijian Song , Zihua Tang , Guoliang Song , Jianguo Zhu , Jingzhang Liu , Haiyang Wang , Yinjiang Zhang
The circulating fluidized bed (CFB) boiler is an essential option, serving as a flexible power source. However, it is notable that CFB boilers exhibit noticeable limitations in rapid load changes. This study delved into the impact of fuel characteristics on CFB load change rate, combustion efficiency, and original NOx emissions using a 2 MW CFB experimental platform. The findings revealed that blending pulverized coal or modified fuel positively influenced the improvement of CFB load change rate, with blending modified fuel showing a more significant effect. Blending the modified fuel and pulverized coal increased the load change rate within the 50%–100% range by 164.4% and 57.3%, respectively. Additionally, blending pulverized coal and modified fuel significantly reduced NOx emissions, although there remained room for improvement in combustion efficiency. Compared to conventional combustion, blending pulverized coal and blending modified fuel decreased NOx emissions by 35.9% and 41.4% at 100% load, respectively.
{"title":"Experimental study on variable load regulation of circulating fluidized bed with high temperature preheated activated fuel","authors":"Weijian Song , Zihua Tang , Guoliang Song , Jianguo Zhu , Jingzhang Liu , Haiyang Wang , Yinjiang Zhang","doi":"10.1016/j.partic.2024.09.007","DOIUrl":"10.1016/j.partic.2024.09.007","url":null,"abstract":"<div><div>The circulating fluidized bed (CFB) boiler is an essential option, serving as a flexible power source. However, it is notable that CFB boilers exhibit noticeable limitations in rapid load changes. This study delved into the impact of fuel characteristics on CFB load change rate, combustion efficiency, and original NO<sub><em>x</em></sub> emissions using a 2 MW CFB experimental platform. The findings revealed that blending pulverized coal or modified fuel positively influenced the improvement of CFB load change rate, with blending modified fuel showing a more significant effect. Blending the modified fuel and pulverized coal increased the load change rate within the 50%–100% range by 164.4% and 57.3%, respectively. Additionally, blending pulverized coal and modified fuel significantly reduced NO<sub><em>x</em></sub> emissions, although there remained room for improvement in combustion efficiency. Compared to conventional combustion, blending pulverized coal and blending modified fuel decreased NO<sub><em>x</em></sub> emissions by 35.9% and 41.4% at 100% load, respectively.</div></div>","PeriodicalId":401,"journal":{"name":"Particuology","volume":"95 ","pages":"Pages 178-188"},"PeriodicalIF":4.1,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142442117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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