Supercapacitors have attracted significant attention in modern devices as a promising solution for electrical energy storage due to their remarkable capability to undergo rapid charge and discharge cycles. While various materials are employed in the construction of supercapacitors, carbon-based materials emerge as a predominant choice within the commercial realm. In present report, our intention is to develop an effective supercapacitor device derived from natural biomass. Therefore, we have synthesized water soluble, monodisperse and fluorescent carbon quantum dots (CQDs) from turmeric leaves (Curcuma caesia) via a single step hydrothermal carbonization. Further, the doctor blade technique was employed to coat a layer of CQDs on stainless steel substrate using PVA as a binder. We observed the functional groups associated with QDs triggers the fast diffusion of ions and transmission of electrons with conducting substrate and electrolyte and thereby effectively charge and discharge mechanism. The supercapacitor based on carbon quantum dots (CQDs) based electrode exhibits exceptional performance characteristics with a remarkable specific capacitance of 468 F/g and highest energy density of 78.6 Wh/kg, superior to the values reported for most carbon-based supercapacitors. Further, we demonstrated the light dependent capacitive enhancement by depositing a thin P3HT layer over CQDs. Moreover, CQDs-based supercapacitor achieves a maximum power density of 733.2 W/kg when operated in a 1 M KOH electrolyte solution and an excellent capacitive retention of about 80 % even after 5000 cycles.
{"title":"Enhancing capacitance performance of functional group assisted carbon quantum dots derived from turmeric plant waste","authors":"S.S. Patil , A.G. Bhosale , S.S. Kundale , T.D. Dongale , S.A. Vanalakar","doi":"10.1016/j.cartre.2024.100370","DOIUrl":"10.1016/j.cartre.2024.100370","url":null,"abstract":"<div><p>Supercapacitors have attracted significant attention in modern devices as a promising solution for electrical energy storage due to their remarkable capability to undergo rapid charge and discharge cycles. While various materials are employed in the construction of supercapacitors, carbon-based materials emerge as a predominant choice within the commercial realm. In present report, our intention is to develop an effective supercapacitor device derived from natural biomass. Therefore, we have synthesized water soluble, monodisperse and fluorescent carbon quantum dots (CQDs) from turmeric leaves (<em>Curcuma caesia</em>) via a single step hydrothermal carbonization. Further, the doctor blade technique was employed to coat a layer of CQDs on stainless steel substrate using PVA as a binder. We observed the functional groups associated with QDs triggers the fast diffusion of ions and transmission of electrons with conducting substrate and electrolyte and thereby effectively charge and discharge mechanism. The supercapacitor based on carbon quantum dots (CQDs) based electrode exhibits exceptional performance characteristics with a remarkable specific capacitance of 468 F/g and highest energy density of 78.6 Wh/kg, superior to the values reported for most carbon-based supercapacitors. Further, we demonstrated the light dependent capacitive enhancement by depositing a thin P3HT layer over CQDs. Moreover, CQDs-based supercapacitor achieves a maximum power density of 733.2 W/kg when operated in a 1 M KOH electrolyte solution and an excellent capacitive retention of about 80 % even after 5000 cycles.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667056924000518/pdfft?md5=fa75c5a3927e1de652870289a8d50b74&pid=1-s2.0-S2667056924000518-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141280054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-01DOI: 10.1016/j.cartre.2024.100366
Mohan Gorle , A. Vijay Kumar , Vatsala Rani Jetti
Eutectic-Magnesium electrolytes are sparsely used electrolytes in Magnesium ion batteries. In this context, readily available less toxic precursors based eutectic electrolytes are attracting increasing interest owing to the focus of sustainable battery development. The unique benefits of magnesium such as high specific capacity, low reduction potential, and remarkable reversibility without dendrimer formation are highly advantages when compare to lithium based batteries. Developing an optimal electrolyte composition is a key area of study in the field of battery technology. With improved cell performance, stability across cycles, and general safety, we hope to reduce unwanted interfacial reactions. In this study, we examined eutectic combination of trimethylamine hydrochloride and aluminium chloride (TMA: AlCl3 = TMA) along with magnesium perchlorate to understand ion-solvation, complexation, thermal stability, ion transport and conduction, and electrochemical stability, certain physico-chemical and electrochemical parameters were evaluated prior to assessing the cell's performance. The salient features being an ionic conductivity (σ) of 6.25×10−3 mS cm−1 at 30 °C, remarkable performance retention with over 90 cycles of operation with the electrolyte and an impressive capacity of 90 mAh/g. The behaviour of ionic conductivity with temperature followed the Vogel-Tammann-Fulcher (VTF) equation. Moreover, the anodic stability around 2.5 V (Mg/Mg2+) when platinum is used as the working electrode endorses the suitability of the electrolyte for use in Rechargeable Magnesium Batteries (RMBs).The promising results of this first investigation open up new possibilities for investigating complementary pairings with the aim of improving the efficiency of magnesium-ion cells.
共晶镁电解质是镁离子电池中很少使用的电解质。在这种情况下,基于毒性较低的易得前驱体的共晶电解质正吸引着越来越多的关注,这也是可持续电池发展的重点所在。与锂电池相比,镁具有高比容量、低还原电位和无树枝状聚合物形成的显著可逆性等独特优势。开发最佳电解质成分是电池技术领域的一个关键研究领域。随着电池性能、循环稳定性和总体安全性的提高,我们希望能减少不必要的界面反应。在这项研究中,我们研究了盐酸三甲胺和氯化铝(TMA:AlCl3 = TMA)与高氯酸镁的共晶组合,以了解离子溶解、络合、热稳定性、离子传输和传导以及电化学稳定性,并在评估电池性能之前评估了某些物理化学和电化学参数。其显著特点是:在 30 °C 时离子电导率(σ)为 6.25×10-3 mS cm-1;在电解质的作用下超过 90 个循环后仍能保持出色的性能;容量高达 90 mAh/g。离子电导率随温度的变化遵循 Vogel-Tammann-Fulcher (VTF) 等式。此外,当使用铂作为工作电极时,阳极稳定性约为 2.5 V(Mg/Mg2+),这证明该电解液适用于可充电镁电池(RMB)。
{"title":"Magnesium-eutectic electrolyte as a winning combination for sustainable battery","authors":"Mohan Gorle , A. Vijay Kumar , Vatsala Rani Jetti","doi":"10.1016/j.cartre.2024.100366","DOIUrl":"10.1016/j.cartre.2024.100366","url":null,"abstract":"<div><p>Eutectic-Magnesium electrolytes are sparsely used electrolytes in Magnesium ion batteries. In this context, readily available less toxic precursors based eutectic electrolytes are attracting increasing interest owing to the focus of sustainable battery development. The unique benefits of magnesium such as high specific capacity, low reduction potential, and remarkable reversibility without dendrimer formation are highly advantages when compare to lithium based batteries. Developing an optimal electrolyte composition is a key area of study in the field of battery technology. With improved cell performance, stability across cycles, and general safety, we hope to reduce unwanted interfacial reactions. In this study, we examined eutectic combination of trimethylamine hydrochloride and aluminium chloride (TMA: AlCl<sub>3</sub> = TMA) along with magnesium perchlorate to understand ion-solvation, complexation, thermal stability, ion transport and conduction, and electrochemical stability, certain physico-chemical and electrochemical parameters were evaluated prior to assessing the cell's performance. The salient features being an ionic conductivity (σ) of 6.25×10<sup>−3</sup> mS cm<sup>−1</sup> at 30 °C, remarkable performance retention with over 90 cycles of operation with the electrolyte and an impressive capacity of 90 mAh/g. The behaviour of ionic conductivity with temperature followed the Vogel-Tammann-Fulcher (VTF) equation. Moreover, the anodic stability around 2.5 V (Mg/Mg<sup>2+</sup>) when platinum is used as the working electrode endorses the suitability of the electrolyte for use in Rechargeable Magnesium Batteries (RMBs).The promising results of this first investigation open up new possibilities for investigating complementary pairings with the aim of improving the efficiency of magnesium-ion cells.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667056924000476/pdfft?md5=33a79e27512c0f01a7e4de13ba2b23b0&pid=1-s2.0-S2667056924000476-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141143804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Use of waste polystyrene as an additive in the preparation of biowaste derived char can provide significant new properties that enhance the performance of the epoxy coating on steel surface. This work establishes a cost-effective Quasi-graphitic carbon (QGC) derived from the co-pyrolysis of Eucalyptus wood chips and polystyrene as a mix in epoxy (EP) matrix for enhanced the coating properties. The QGC material was characterized by FTIR, XRD, Raman, SEM-EDX, TGA, etc. Results show the incorporation of 0.1 wt.% QGC to the EP matrix enhances corrosion resistance by 98.6 % and boosts mechanical properties with a 245.45 % increase in hardness and a 57.31 % rise in elastic modulus compared to pure EP coatings. Microscopic analysis reveals a smoother, more compact surface with fewer structural defects comapred to pure EP coating. Adhesion tests score the category of 4B, 5B, and water contact angle improve to 102.8°, compared to 61.6° for pure EP coatings. These eco-friendly materials, created through environmentally conscious processes can be a safe alternative to the conventional toxic chemicals used to protect against corrosion,particularly in marine environments.
使用废弃聚苯乙烯作为制备生物废料衍生炭的添加剂可提供显著的新特性,从而提高钢表面环氧涂层的性能。这项研究利用桉树木屑和聚苯乙烯的共热解过程制备了一种经济有效的准石墨化碳(QGC),并将其混合在环氧树脂(EP)基质中,以增强涂层性能。傅立叶变换红外光谱(FTIR)、X 射线衍射(XRD)、拉曼光谱(Raman)、扫描电子显微镜(SEM-EDX)、热重分析(TGA)等对 QGC 材料进行了表征。结果表明,与纯 EP 涂层相比,在 EP 基体中加入 0.1 wt.% 的 QGC 可提高 98.6 % 的耐腐蚀性,并增强机械性能,硬度提高了 245.45 %,弹性模量提高了 57.31 %。显微分析表明,与纯 EP 涂层相比,该涂层表面更光滑、更紧凑,结构缺陷更少。附着力测试结果为 4B、5B 级,水接触角提高到 102.8°,而纯 EP 涂料的水接触角为 61.6°。这些通过环保工艺生产的环保材料可以安全地替代用于防腐蚀的传统有毒化学品,尤其是在海洋环境中。
{"title":"Co-pyrolysis of waste wood and plastic to produce quasi graphitic carbon: enhanced biochar properties for metal coatings through safe sequestration and green technology","authors":"Anu Verma , Dhiman Banik , Chandra Sekhar Tiwary , Jayanta Bhattacharya","doi":"10.1016/j.cartre.2024.100369","DOIUrl":"10.1016/j.cartre.2024.100369","url":null,"abstract":"<div><p>Use of waste polystyrene as an additive in the preparation of biowaste derived char can provide significant new properties that enhance the performance of the epoxy coating on steel surface. This work establishes a cost-effective Quasi-graphitic carbon (QGC) derived from the co-pyrolysis of Eucalyptus wood chips and polystyrene as a mix in epoxy (EP) matrix for enhanced the coating properties. The QGC material was characterized by FTIR, XRD, Raman, SEM-EDX, TGA, etc. Results show the incorporation of 0.1 wt.% QGC to the EP matrix enhances corrosion resistance by 98.6 % and boosts mechanical properties with a 245.45 % increase in hardness and a 57.31 % rise in elastic modulus compared to pure EP coatings. Microscopic analysis reveals a smoother, more compact surface with fewer structural defects comapred to pure EP coating. Adhesion tests score the category of 4B, 5B, and water contact angle improve to 102.8°, compared to 61.6° for pure EP coatings. These eco-friendly materials, created through environmentally conscious processes can be a safe alternative to the conventional toxic chemicals used to protect against corrosion,particularly in marine environments.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667056924000506/pdfft?md5=613506d177e44393bda4063151f2994c&pid=1-s2.0-S2667056924000506-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141281707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-01DOI: 10.1016/j.cartre.2024.100371
Lijun Qu , Haoyu Zhang , Shengwei Huang , Hai Wang , Shihai Yan
As an important intermediate for dual carbon targets, catalytic CO oxidation under mild conditions has received sufficient attention, as the reaction mechanism is directly related to the type of employed catalyst. High performance computing is performed with density functional theory to elucidate the mechanism of CO oxidation catalyzed by sulfur doped fullerene (C60-xSx (x = 1 ∼ 3)). The total activation energy for the first CO oxidation on C59S, C58S2, and C57S3 increases gradually, as implies that the CO oxidation on C59S should be easier than those on the other two dopants. Distinct electrons (0.852 e and 1.479 e) are transferred to oxygen atoms (O2) from C59S with the adsorption of O2 and CO. There is no synergistic effect for the doping S atoms. All elementary reactions on C59S are exothermic processes. This means that C59S is a potential material for addressing environmental protection issues and H2 purification for fuel cell applications.
作为双碳目标的重要中间体,温和条件下催化 CO 氧化反应受到了足够的关注,因为反应机理与所使用催化剂的类型直接相关。我们利用密度泛函理论进行了高性能计算,以阐明掺硫富勒烯(C60-xSx (x = 1 ∼ 3))催化 CO 氧化的机理。C59S、C58S2 和 C57S3 上第一次 CO 氧化的总活化能逐渐增加,这意味着 C59S 上的 CO 氧化比其他两种掺杂物上的 CO 氧化更容易。随着 O2 和 CO 的吸附,不同的电子(0.852 e 和 1.479 e)从 C59S 转移到氧原子(O2)上。掺杂 S 原子不会产生协同效应。C59S 上的所有基本反应都是放热过程。这意味着 C59S 是解决环境保护问题和燃料电池应用中 H2 净化问题的潜在材料。
{"title":"Unveiling the mechanism of CO oxidation catalyzed by sulfur-doped fullerenes with the DFT calculations","authors":"Lijun Qu , Haoyu Zhang , Shengwei Huang , Hai Wang , Shihai Yan","doi":"10.1016/j.cartre.2024.100371","DOIUrl":"https://doi.org/10.1016/j.cartre.2024.100371","url":null,"abstract":"<div><p>As an important intermediate for dual carbon targets, catalytic CO oxidation under mild conditions has received sufficient attention, as the reaction mechanism is directly related to the type of employed catalyst. High performance computing is performed with density functional theory to elucidate the mechanism of CO oxidation catalyzed by sulfur doped fullerene (C<em><sub>60-x</sub></em>S<em><sub>x</sub></em> (<em>x</em> = 1 ∼ 3)). The total activation energy for the first CO oxidation on C<em><sub>59</sub></em>S, C<em><sub>58</sub></em>S<em><sub>2</sub></em>, and C<em><sub>57</sub></em>S<em><sub>3</sub></em> increases gradually, as implies that the CO oxidation on C<em><sub>59</sub></em>S should be easier than those on the other two dopants. Distinct electrons (0.852 <em>e</em> and 1.479 <em>e</em>) are transferred to oxygen atoms (O<sub>2</sub>) from C<em><sub>59</sub></em>S with the adsorption of O<sub>2</sub> and CO. There is no synergistic effect for the doping S atoms. All elementary reactions on C<em><sub>59</sub></em>S are exothermic processes. This means that C<em><sub>59</sub></em>S is a potential material for addressing environmental protection issues and H<sub>2</sub> purification for fuel cell applications.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S266705692400052X/pdfft?md5=54fad390ab8f9b1a7841e3741df6655a&pid=1-s2.0-S266705692400052X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141291952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-19DOI: 10.1016/j.cartre.2024.100368
A.A. Stepashkin , N.Yu. Nikitin
High-strength and high-modulus carbon fibers are the basis of many composite materials used in power and automotive engineering as well as other mechanical engineering fields. Superstructural thermoplastic binders—like PPS, PSU, PES, and PEEK—are emerging quickly as a binder material. The mechanical properties of composite materials, especially tensile strength, are improved when high-strength and high-modulus fibers are combined with superstructural thermoplastic binders. However, the type of carbon fiber used, the concentration of thermoplastic binder, and the specifics of the production process all have a significant impact on the final mechanical properties of the composite material. As such, predicting these properties requires both a thorough analysis and a trustworthy mathematical model that predicts mechanical properties (tensile strength).
The study that is being presented takes a thorough approach to statistical analysis and model building that anticipates the tensile strength of composite material samples made of carbon filaments that have been impregnated with polysulfone (PSU), a thermoplastic polymer.
PSU thermoplastic polymer was used as a binder, and 817 samples of composite material with high-strength and high-modulus carbon fibers of four different grades were subjected to a thorough statistical analysis of the tensile test findings.
Nine distinct regression models and four CNN-based models with three distinct neuron activation functions were constructed based on the statistical analysis. The built-in models forecast the composite material's ultimate strength based on the specimen loading circumstances, filler qualities, and composition.
Significant differences were found in the mechanical properties of carbon fibers of different grades and types (high-strength and high-modulus) based on statistical analysis of the results of tensile tests. The results of Spearman's correlation study indicated a medium positive correlation between ultimate strength and polymer concentration and a weak negative association between ultimate strength and the density of the carbon fiber contained in the composite material. The strain corresponding to the ultimate strength and fiber density were found to have a medium negative correlation, whereas the polymer concentration showed a medium positive correlation. In the composite material, a very slight negative association was discovered between the concentration of polymers and the density of carbon fibers.
Test results were split into two categories while creating CNN and regression models: 75 % were used for model testing and 25 % were used for training. The CNN model with three layers of hidden parameters produced the best prediction results; the RMSE was 142.948 MPa and the Spearman correlation coefficient between the test strength and the anticipated values was 0.988.
Regression models' sensitivity analysis revealed that, up to a response variable (tens
{"title":"Statistical analysis, regression, and neural network modeling of the tensile strength of thermoplastic unidirectional carbon fiber-polysulfone composites","authors":"A.A. Stepashkin , N.Yu. Nikitin","doi":"10.1016/j.cartre.2024.100368","DOIUrl":"10.1016/j.cartre.2024.100368","url":null,"abstract":"<div><p>High-strength and high-modulus carbon fibers are the basis of many composite materials used in power and automotive engineering as well as other mechanical engineering fields. Superstructural thermoplastic binders—like PPS, PSU, PES, and PEEK—are emerging quickly as a binder material. The mechanical properties of composite materials, especially tensile strength, are improved when high-strength and high-modulus fibers are combined with superstructural thermoplastic binders. However, the type of carbon fiber used, the concentration of thermoplastic binder, and the specifics of the production process all have a significant impact on the final mechanical properties of the composite material. As such, predicting these properties requires both a thorough analysis and a trustworthy mathematical model that predicts mechanical properties (tensile strength).</p><p>The study that is being presented takes a thorough approach to statistical analysis and model building that anticipates the tensile strength of composite material samples made of carbon filaments that have been impregnated with polysulfone (PSU), a thermoplastic polymer.</p><p>PSU thermoplastic polymer was used as a binder, and 817 samples of composite material with high-strength and high-modulus carbon fibers of four different grades were subjected to a thorough statistical analysis of the tensile test findings.</p><p>Nine distinct regression models and four CNN-based models with three distinct neuron activation functions were constructed based on the statistical analysis. The built-in models forecast the composite material's ultimate strength based on the specimen loading circumstances, filler qualities, and composition.</p><p>Significant differences were found in the mechanical properties of carbon fibers of different grades and types (high-strength and high-modulus) based on statistical analysis of the results of tensile tests. The results of Spearman's correlation study indicated a medium positive correlation between ultimate strength and polymer concentration and a weak negative association between ultimate strength and the density of the carbon fiber contained in the composite material. The strain corresponding to the ultimate strength and fiber density were found to have a medium negative correlation, whereas the polymer concentration showed a medium positive correlation. In the composite material, a very slight negative association was discovered between the concentration of polymers and the density of carbon fibers.</p><p>Test results were split into two categories while creating CNN and regression models: 75 % were used for model testing and 25 % were used for training. The CNN model with three layers of hidden parameters produced the best prediction results; the RMSE was 142.948 MPa and the Spearman correlation coefficient between the test strength and the anticipated values was 0.988.</p><p>Regression models' sensitivity analysis revealed that, up to a response variable (tens","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S266705692400049X/pdfft?md5=959e6e55b7cd43717c86b632562a995b&pid=1-s2.0-S266705692400049X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141144637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In response to the escalating demand for cleaner energy sources, this study investigates the potential of carefully selected functionalized graphene-based materials for enhancing hydrogen sulphide (H2S) removal in fuel streams, utilizing semi-empirical and density functional theory (DFT) calculations for molecular-level insights. A particular focus is placed on aliphatic methyl (-CH), alcohol (-COH), carboxylate (-COO), carbonyl (-CO), and acid (-COOH) -functionalized graphene, aiming to bridge gaps between desulphurization methods and graphene applications, specifically targeting H2S removal. Through extensive computational analyses, the research unravels the intricate interactions between chosen functionalized graphene materials and sulfur compounds like H2S, emphasizing mechanisms contributing to improved desulphurization efficiency. Our study's analysis highlights the superior performance of carboxylate (-COO)-functionalized graphene, mainly through dissociative adsorption mechanisms. The study systematically evaluates the influence of selected functional groups on adsorption activity, emphasizing the significance of dissociation. Overall, this research advances desulphurization strategies and underscores the potential of functionalized graphene in sustainable energy solutions.
{"title":"Enhancing hydrogen sulphide removal efficiency: A DFT study on selected functionalized graphene-based materials","authors":"Toyese Oyegoke , Adnan Aliyu , Maryann I. Uzochuwu , Yahweh Hassan","doi":"10.1016/j.cartre.2024.100362","DOIUrl":"10.1016/j.cartre.2024.100362","url":null,"abstract":"<div><p>In response to the escalating demand for cleaner energy sources, this study investigates the potential of carefully selected functionalized graphene-based materials for enhancing hydrogen sulphide (H<sub>2</sub>S) removal in fuel streams, utilizing semi-empirical and density functional theory (DFT) calculations for molecular-level insights. A particular focus is placed on aliphatic methyl (-CH), alcohol (-COH), carboxylate (-COO), carbonyl (-CO), and acid (-COOH) -functionalized graphene, aiming to bridge gaps between desulphurization methods and graphene applications, specifically targeting H<sub>2</sub>S removal. Through extensive computational analyses, the research unravels the intricate interactions between chosen functionalized graphene materials and sulfur compounds like H<sub>2</sub>S, emphasizing mechanisms contributing to improved desulphurization efficiency. Our study's analysis highlights the superior performance of carboxylate (-COO)-functionalized graphene, mainly through dissociative adsorption mechanisms. The study systematically evaluates the influence of selected functional groups on adsorption activity, emphasizing the significance of dissociation. Overall, this research advances desulphurization strategies and underscores the potential of functionalized graphene in sustainable energy solutions.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667056924000439/pdfft?md5=6abc0f172c7b391a603bca7fe8906b27&pid=1-s2.0-S2667056924000439-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141049376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-09DOI: 10.1016/j.cartre.2024.100361
Amirhosein Riahi , Ethan Heggem , Mario Caccia , Richard LaDouceur
Due to the excessive consumption of fossil fuels, which leads to significant greenhouse gas emissions and rapid climate change, it is crucial to develop various carbon capture and sequestration strategies. CO2 sequestration in solid, porous adsorbents like low-cost biochar has emerged as a promising approach to achieve this goal. However, slow adsorption kinetics are one of the issues that limit the widespread use of this approach. While the characteristics of the biochar are important and impact CO2 adsorption, the conditions under which adsorption occurs are equally critical. In this work, a novel strategy is proposed to accelerate the CO2 uptake rate on carbon adsorbents by utilizing Low-Frequency High Amplitude resonant vibratory mixing during the adsorption process. With this approach, the rate of adsorption (characterized by the adsorption rate constant) exhibits an increase of 46.6% and 91.3%, as calculated by two different kinetic models: the Weber and Morris model, and the Pseudo-First-Order model. Experimental observations indicate that adsorption kinetics have a mixed control between external/internal diffusion and the physisorption process. Resonant vibrations enhance system energy, promoting collisions between CO2 molecules and carbon surfaces, subsequently improving CO2 transport and surface/gas interactions, facilitating the adsorption process and thus leading to enhanced kinetic rates. Furthermore, an analysis of variance determined the sensitivity of CO2 uptake to several operating parameters associated with the resonant vibrations. This analysis indicated that the adsorption of CO2 is most sensitive to the level of fill of the adsorption vessel and the time exposed to resonant vibrations.
{"title":"Enhancement of CO2 Adsorption Kinetics onto Carbon by Low-Frequency High Amplitude Resonant Vibrations","authors":"Amirhosein Riahi , Ethan Heggem , Mario Caccia , Richard LaDouceur","doi":"10.1016/j.cartre.2024.100361","DOIUrl":"https://doi.org/10.1016/j.cartre.2024.100361","url":null,"abstract":"<div><p>Due to the excessive consumption of fossil fuels, which leads to significant greenhouse gas emissions and rapid climate change, it is crucial to develop various carbon capture and sequestration strategies. CO<sub>2</sub> sequestration in solid, porous adsorbents like low-cost biochar has emerged as a promising approach to achieve this goal. However, slow adsorption kinetics are one of the issues that limit the widespread use of this approach. While the characteristics of the biochar are important and impact CO<sub>2</sub> adsorption, the conditions under which adsorption occurs are equally critical. In this work, a novel strategy is proposed to accelerate the CO<sub>2</sub> uptake rate on carbon adsorbents by utilizing Low-Frequency High Amplitude resonant vibratory mixing during the adsorption process. With this approach, the rate of adsorption (characterized by the adsorption rate constant) exhibits an increase of 46.6% and 91.3%, as calculated by two different kinetic models: the Weber and Morris model, and the Pseudo-First-Order model. Experimental observations indicate that adsorption kinetics have a mixed control between external/internal diffusion and the physisorption process. Resonant vibrations enhance system energy, promoting collisions between CO<sub>2</sub> molecules and carbon surfaces, subsequently improving CO<sub>2</sub> transport and surface/gas interactions, facilitating the adsorption process and thus leading to enhanced kinetic rates. Furthermore, an analysis of variance determined the sensitivity of CO<sub>2</sub> uptake to several operating parameters associated with the resonant vibrations. This analysis indicated that the adsorption of CO<sub>2</sub> is most sensitive to the level of fill of the adsorption vessel and the time exposed to resonant vibrations.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667056924000427/pdfft?md5=84a407f558efb99d306a37840dfadc5c&pid=1-s2.0-S2667056924000427-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140914456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-07DOI: 10.1016/j.cartre.2024.100360
Samuel Escobar Veras , Ernesto Espada , Solimar Collazo , Marcel Grau , Rajesh Katiyar , Vladimir I. Makarov , Brad R. Weiner , Gerardo Morell
Octadecylphosphonic acid self-assembled monolayers were used as a combined carbon and hydrogen source to grow graphene films on sapphire substrates via hot filament chemical vapor deposition. The functionalized substrates were sealed with a thin Cu film and heated to 950°C under Ar flow. After synthesis, the Cu was etched away. The graphene samples then underwent a hydrogenation treatment in the same reactor setup, exposed to a CH4/H2 gas mixture at 820°C for 2 hours. The structure and properties of the graphene films before and after hydrogenation were characterized. Raman spectroscopy was employed to probe the defect-related bands and C-H bonding. X-ray diffraction provided insights into the crystalline structure and interlayer spacing. The ferromagnetic response was measured using a PPMS system across a range of temperatures and magnetic fields. XPS was used to assess the chemical composition and bonding. This multi-step process enabled a detailed evaluation of the novel synthesis protocol and its effects on the resulting hydrogenated graphene material.
{"title":"Hydrogenated graphene systems: A novel growth and hydrogenation process","authors":"Samuel Escobar Veras , Ernesto Espada , Solimar Collazo , Marcel Grau , Rajesh Katiyar , Vladimir I. Makarov , Brad R. Weiner , Gerardo Morell","doi":"10.1016/j.cartre.2024.100360","DOIUrl":"https://doi.org/10.1016/j.cartre.2024.100360","url":null,"abstract":"<div><p>Octadecylphosphonic acid self-assembled monolayers were used as a combined carbon and hydrogen source to grow graphene films on sapphire substrates via hot filament chemical vapor deposition. The functionalized substrates were sealed with a thin Cu film and heated to 950°C under Ar flow. After synthesis, the Cu was etched away. The graphene samples then underwent a hydrogenation treatment in the same reactor setup, exposed to a CH<sub>4</sub>/H<sub>2</sub> gas mixture at 820°C for 2 hours. The structure and properties of the graphene films before and after hydrogenation were characterized. Raman spectroscopy was employed to probe the defect-related bands and C-H bonding. X-ray diffraction provided insights into the crystalline structure and interlayer spacing. The ferromagnetic response was measured using a PPMS system across a range of temperatures and magnetic fields. XPS was used to assess the chemical composition and bonding. This multi-step process enabled a detailed evaluation of the novel synthesis protocol and its effects on the resulting hydrogenated graphene material.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667056924000415/pdfft?md5=f0c52cad96fc046310457d1ccb58b371&pid=1-s2.0-S2667056924000415-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140914455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this study, the electrochemical properties of bioderived activated carbon-based electrodes for supercapacitors formed using a sintered ceramic binder were investigated. Activated carbon derived from Jack wood tree (Artocarpus heterophyllus) with variable amounts of TiO2 nanoparticles as a binder, were used as electrodes in order to get good, activated carbon films on FTO substrates. No other binders were used in this study since most conventional binders devastate the electrical conductivity in the films. Furthermore, TiO2 has higher temperature tolerance compared to polymeric binders thus the electrode prepared can be used in wider applications. A series of electrochemical double-layer capacitors were fabricated and characterized by cyclic voltammetry and galvanostatic charge-discharge measurements. The supercapacitors prepared showed double-layer capacitive behavior. The electrodes that contain 90 % activated carbon and 10 % TiO2 show optimum performance along with an impressive specific capacitance of 147 F g−1 at 2 mV s−1 scan rate. This supercapacitor exhibits a power density of 68.5 W kg−1 while the energy density is 8.02 Wh kg−1. When the power density is as high as 1186.51 W kg−1 the energy density drops to 5.71 Wh kg−1. According to cyclic voltammetry measurements taken for 1000 cycles, the supercapacitor shows excellent cycle stability without any traces of capacitance drop.
{"title":"Activated carbon synthesized from Jack wood biochar for high performing biomass derived composite double layer supercapacitors","authors":"T.M.W.J. Bandara , A.M.B.S. Alahakoon , B.-E. Mellander , I. Albinsson","doi":"10.1016/j.cartre.2024.100359","DOIUrl":"https://doi.org/10.1016/j.cartre.2024.100359","url":null,"abstract":"<div><p>In this study, the electrochemical properties of bioderived activated carbon-based electrodes for supercapacitors formed using a sintered ceramic binder were investigated. Activated carbon derived from Jack wood tree (<em>Artocarpus heterophyllus</em>) with variable amounts of TiO<sub>2</sub> nanoparticles as a binder, were used as electrodes in order to get good, activated carbon films on FTO substrates. No other binders were used in this study since most conventional binders devastate the electrical conductivity in the films. Furthermore, TiO<sub>2</sub> has higher temperature tolerance compared to polymeric binders thus the electrode prepared can be used in wider applications. A series of electrochemical double-layer capacitors were fabricated and characterized by cyclic voltammetry and galvanostatic charge-discharge measurements. The supercapacitors prepared showed double-layer capacitive behavior. The electrodes that contain 90 % activated carbon and 10 % TiO<sub>2</sub> show optimum performance along with an impressive specific capacitance of 147 F g<sup>−1</sup> at 2 mV s<sup>−1</sup> scan rate. This supercapacitor exhibits a power density of 68.5 W kg<sup>−1</sup> while the energy density is 8.02 Wh kg<sup>−1</sup>. When the power density is as high as 1186.51 W kg<sup>−1</sup> the energy density drops to 5.71 Wh kg<sup>−1</sup>. According to cyclic voltammetry measurements taken for 1000 cycles, the supercapacitor shows excellent cycle stability without any traces of capacitance drop.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667056924000403/pdfft?md5=087abb28222a21382885b36f98cb089e&pid=1-s2.0-S2667056924000403-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140824204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The present work focuses on the synthesis of hybrid La2CoCrO6/Co3O4/rGO composite via solvothermal technique for supercapacitor application. X-ray diffraction, field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, Brunauer-Emmett-Teller (BET), and Barrett-Joyner-Halenda analyses are employed to assess phase structure, morphology, chemical state, surface area, and porosity of synthesized materials, respectively. The formation of mesoporous spheres is confirmed through FESEM and BET analysis. The inclusion of redox additive KMnO4 in KOH electrolyte enhances the accessibility of electrochemical sites in the mesoporous spheres of the La2CoCrO6/Co3O4/rGO electrode, resulting in excellent charge storage. Electrochemical analysis of the La2CoCrO6/Co3O4 exhibits specific capacitance of 633.2 F/g at 2 A/g in a redox electrolyte (6 M KOH + 0.05 M KMnO4) with capacitive retention of approximately 81 % over 5000 cycles. Furthermore, the addition of rGO improves the overall performance of La2CoCrO6/Co3O4/rGO composite (763.9 F/g at 2 A/g with capacitive retention of approximately 86 %). The electrochemical analysis of hybrid La2CoCrO6/Co3O4/rGO composite showed improved performance, owing to the synergy of double perovskite (La2CoCrO6), cobalt oxide (Co3O4), and reduced graphene oxide (rGO). These findings suggest promising applications for the material in advanced energy storage devices.
本研究的重点是通过溶热技术合成用于超级电容器的混合 La2CoCrO6/Co3O4/rGO 复合材料。通过 X 射线衍射、场发射扫描电子显微镜(FESEM)、高分辨率透射电子显微镜、X 射线光电子能谱、Brunauer-Emmett-Teller(BET)和 Barrett-Joyner-Halenda 分析,分别评估了合成材料的相结构、形态、化学状态、表面积和孔隙率。FESEM 和 BET 分析证实了介孔球体的形成。在 KOH 电解液中加入氧化还原添加剂 KMnO4 提高了 La2CoCrO6/Co3O4/rGO 电极介孔球体中电化学位点的可及性,从而实现了出色的电荷存储。La2CoCrO6/Co3O4 的电化学分析表明,在氧化还原电解质(6 M KOH + 0.05 M KMnO4)中,2 A/g时的比电容为 633.2 F/g,5000 次循环后的电容保持率约为 81%。此外,添加 rGO 还提高了 La2CoCrO6/Co3O4/rGO 复合材料的整体性能(2 A/g 时为 763.9 F/g,电容保持率约为 86%)。混合 La2CoCrO6/Co3O4/rGO 复合材料的电化学分析表明,由于双过氧化物(La2CoCrO6)、氧化钴(Co3O4)和还原氧化石墨烯(rGO)的协同作用,其性能得到了提高。这些发现表明,这种材料在先进储能设备中的应用前景广阔。
{"title":"Electrochemical evaluation of hybrid La2CoCrO6/Co3O4/rGO composite for enhanced supercapacitor performance","authors":"Deeksha Nagpal , Anup Singh , Ajay Vasishth , Ranbir Singh , Ashok Kumar","doi":"10.1016/j.cartre.2024.100358","DOIUrl":"https://doi.org/10.1016/j.cartre.2024.100358","url":null,"abstract":"<div><p>The present work focuses on the synthesis of hybrid La<sub>2</sub>CoCrO<sub>6</sub>/Co<sub>3</sub>O<sub>4</sub>/rGO composite via solvothermal technique for supercapacitor application. X-ray diffraction, field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, Brunauer-Emmett-Teller (BET), and Barrett-Joyner-Halenda analyses are employed to assess phase structure, morphology, chemical state, surface area, and porosity of synthesized materials, respectively. The formation of mesoporous spheres is confirmed through FESEM and BET analysis. The inclusion of redox additive KMnO<sub>4</sub> in KOH electrolyte enhances the accessibility of electrochemical sites in the mesoporous spheres of the La<sub>2</sub>CoCrO<sub>6</sub>/Co<sub>3</sub>O<sub>4</sub>/rGO electrode, resulting in excellent charge storage. Electrochemical analysis of the La<sub>2</sub>CoCrO<sub>6</sub>/Co<sub>3</sub>O<sub>4</sub> exhibits specific capacitance of 633.2 F/g at 2 A/g in a redox electrolyte (6 M KOH + 0.05 M KMnO<sub>4</sub>) with capacitive retention of approximately 81 % over 5000 cycles. Furthermore, the addition of rGO improves the overall performance of La<sub>2</sub>CoCrO<sub>6</sub>/Co<sub>3</sub>O<sub>4</sub>/rGO composite (763.9 F/g at 2 A/g with capacitive retention of approximately 86 %). The electrochemical analysis of hybrid La<sub>2</sub>CoCrO<sub>6</sub>/Co<sub>3</sub>O<sub>4</sub>/rGO composite showed improved performance, owing to the synergy of double perovskite (La<sub>2</sub>CoCrO<sub>6</sub>), cobalt oxide (Co<sub>3</sub>O<sub>4</sub>), and reduced graphene oxide (rGO). These findings suggest promising applications for the material in advanced energy storage devices.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667056924000397/pdfft?md5=47f22b67660b774f7edb08b0e629ba00&pid=1-s2.0-S2667056924000397-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140816990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}