Pub Date : 2024-07-09DOI: 10.1007/s42823-024-00756-8
Kyeong Nan Kim, Seok Chang Kang, Sang Wan Seo, Deok Jae Seo, Ji Sun Im, Soo Hong Lee, Jong Yeul Seog
Si-based anodes are promising alternatives to graphite owing to their high capacities. However, their practical application is hindered by severe volume expansion during cycling. Herein, we propose employing a carbon support to address this challenge and utilize Si-based anode materials for lithium-ion batteries (LIBs). Specifically, carbon supports with various pore structures were prepared through KOH and NaOH activation of the pitch. In addition, Si was deposited into the carbon support pores via SiH4 chemical vapor deposition (CVD), and to enhance the conductivity and mechanical stability, a carbon coating was applied via CH4 CVD. The electrochemical performance of the C/Si/C composites was assessed, providing insights into their capacity retention rates, cycling stability, rate capability, and lithium-ion diffusion coefficients. Notably, the macrostructure of the carbon support differed significantly depending on the activation agent used. More importantly, the macrostructure of the carbon support significantly affected the Si deposition behavior and enhanced the stability by mitigating the volume expansion of the Si particles. This study elucidated the crucial role of the macrostructure of carbon supports in optimizing Si-based anode materials for LIBs, providing valuable guidance for the design and development of high-performance energy-storage systems.
{"title":"Effects of macrostructure of carbon support in preparation of C/Six/C anode materials for lithium-ion batteries via silane decomposition","authors":"Kyeong Nan Kim, Seok Chang Kang, Sang Wan Seo, Deok Jae Seo, Ji Sun Im, Soo Hong Lee, Jong Yeul Seog","doi":"10.1007/s42823-024-00756-8","DOIUrl":"https://doi.org/10.1007/s42823-024-00756-8","url":null,"abstract":"<p>Si-based anodes are promising alternatives to graphite owing to their high capacities. However, their practical application is hindered by severe volume expansion during cycling. Herein, we propose employing a carbon support to address this challenge and utilize Si-based anode materials for lithium-ion batteries (LIBs). Specifically, carbon supports with various pore structures were prepared through KOH and NaOH activation of the pitch. In addition, Si was deposited into the carbon support pores via SiH<sub>4</sub> chemical vapor deposition (CVD), and to enhance the conductivity and mechanical stability, a carbon coating was applied via CH<sub>4</sub> CVD. The electrochemical performance of the C/Si/C composites was assessed, providing insights into their capacity retention rates, cycling stability, rate capability, and lithium-ion diffusion coefficients. Notably, the macrostructure of the carbon support differed significantly depending on the activation agent used. More importantly, the macrostructure of the carbon support significantly affected the Si deposition behavior and enhanced the stability by mitigating the volume expansion of the Si particles. This study elucidated the crucial role of the macrostructure of carbon supports in optimizing Si-based anode materials for LIBs, providing valuable guidance for the design and development of high-performance energy-storage systems.</p>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141575211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 : 2024-07-07DOI: 10.1007/s42823-024-00774-6
Yasser Zare, Muhammad Tajammal Munir, Kyong Yop Rhee, Soo-Jin Park
In this work, the depth of the interphase in graphene polymer systems is determined by the properties of graphene and interfacial parameters. Furthermore, the actual volume fraction and percolation onset of the nanosheets are characterized by the actual inverse aspect ratio, interphase depth, and tunneling distance. In addition, the dimensions of graphene, along with interfacial/interphase properties and tunneling characteristics, are utilized to develop the power-law equation for the conductivity of graphene-filled composites. Using the derived equations, the interphase depth, percolation onset, and nanocomposite conductivity are graphed against various ranges of the aforementioned factors. Moreover, numerous experimental data points for percolation onset and conductivity are presented to validate the equations. The optimal levels for interphase depth, percolation onset, and conductivity are achieved through high interfacial conductivity and large graphene nanosheets. In addition, increased nanocomposite conductivity can be attained with thinner nanosheets, a larger tunneling distance, and a thicker interphase. The calculations highlight the considerable impacts of interfacial/interphase factors and tunneling distance on the percolation onset. The highest nanocomposite conductivity of 0.008 S/m is acquired by the highest interfacial conduction of 900 S/m and graphene length (D) of 5 μm, while an insulated sample is observed at D < 1.2 μm. Therefore, higher interfacial conduction and larger nanosheets cause the higher nanocomposite conductivity, but the short nanosheets cannot promote the conductivity.
{"title":"Advanced modeling of conductivity in graphene–polymer nanocomposites: insights into interface and tunneling characteristics","authors":"Yasser Zare, Muhammad Tajammal Munir, Kyong Yop Rhee, Soo-Jin Park","doi":"10.1007/s42823-024-00774-6","DOIUrl":"https://doi.org/10.1007/s42823-024-00774-6","url":null,"abstract":"<p>In this work, the depth of the interphase in graphene polymer systems is determined by the properties of graphene and interfacial parameters. Furthermore, the actual volume fraction and percolation onset of the nanosheets are characterized by the actual inverse aspect ratio, interphase depth, and tunneling distance. In addition, the dimensions of graphene, along with interfacial/interphase properties and tunneling characteristics, are utilized to develop the power-law equation for the conductivity of graphene-filled composites. Using the derived equations, the interphase depth, percolation onset, and nanocomposite conductivity are graphed against various ranges of the aforementioned factors. Moreover, numerous experimental data points for percolation onset and conductivity are presented to validate the equations. The optimal levels for interphase depth, percolation onset, and conductivity are achieved through high interfacial conductivity and large graphene nanosheets. In addition, increased nanocomposite conductivity can be attained with thinner nanosheets, a larger tunneling distance, and a thicker interphase. The calculations highlight the considerable impacts of interfacial/interphase factors and tunneling distance on the percolation onset. The highest nanocomposite conductivity of 0.008 S/m is acquired by the highest interfacial conduction of 900 S/m and graphene length (D) of 5 μm, while an insulated sample is observed at <i>D</i> < 1.2 μm. Therefore, higher interfacial conduction and larger nanosheets cause the higher nanocomposite conductivity, but the short nanosheets cannot promote the conductivity.</p>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141575055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 : 2024-07-06DOI: 10.1007/s42823-024-00775-5
Jeong-A Kim, Dong-Kyu Kim, Hyeung-Keun Shin, Sang-Won Jeong, Young-Hyun Hong, Byeong-Jun Kang, Wook Ahn, Jagadeesh Sure, Hyun-Kyung Kim
Graphene has been extensively investigated as a host material for Li metal anodes owing to its light weight, high electrical conductivity, high surface area, and exceptional mechanical rigidity. Many studies have focused on assembling two-dimensional (2D) graphene sheets into three-dimensional (3D) forms, such as lamination, spheres, and carbon nanotubes; however, little attention has been paid to the technology of modifying 2D graphene sheets. Herein, nanoperforated graphene (NPG) was fabricated through a relatively straightforward process employing metal oxide catalysts based on aqueous solutions. Nanoperforations exhibited a size of approximately 5 nm and were introduced on the graphene sheet and lithiophilic carbonyl groups (C = O) at the edges, facilitating the rapid diffusion of Li+ and lowering the Li nucleation overpotential. In comparison to the reduced graphene oxide (RGO) host, the NPG host exhibited a lower lithium nucleation overpotential and a stable overpotential of ~ 30 mV for over 150 cycles as a stable host structure as a Li metal anode for Li metal batteries.
{"title":"Nanoperforated graphene hosts for stable lithium metal anodes","authors":"Jeong-A Kim, Dong-Kyu Kim, Hyeung-Keun Shin, Sang-Won Jeong, Young-Hyun Hong, Byeong-Jun Kang, Wook Ahn, Jagadeesh Sure, Hyun-Kyung Kim","doi":"10.1007/s42823-024-00775-5","DOIUrl":"https://doi.org/10.1007/s42823-024-00775-5","url":null,"abstract":"<p>Graphene has been extensively investigated as a host material for Li metal anodes owing to its light weight, high electrical conductivity, high surface area, and exceptional mechanical rigidity. Many studies have focused on assembling two-dimensional (2D) graphene sheets into three-dimensional (3D) forms, such as lamination, spheres, and carbon nanotubes; however, little attention has been paid to the technology of modifying 2D graphene sheets. Herein, nanoperforated graphene (NPG) was fabricated through a relatively straightforward process employing metal oxide catalysts based on aqueous solutions. Nanoperforations exhibited a size of approximately 5 nm and were introduced on the graphene sheet and lithiophilic carbonyl groups (C = O) at the edges, facilitating the rapid diffusion of Li<sup>+</sup> and lowering the Li nucleation overpotential. In comparison to the reduced graphene oxide (RGO) host, the NPG host exhibited a lower lithium nucleation overpotential and a stable overpotential of ~ 30 mV for over 150 cycles as a stable host structure as a Li metal anode for Li metal batteries.</p>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141575056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 : 2024-07-05DOI: 10.1007/s42823-024-00771-9
Junmei Luo, Shufeng Bo, Seohyun Park, Beom-Kyeong Park, Oi Lun Li
Iron selenides with high capacity and excellent chemical properties have been considered as outstanding anodes for alkali metal-ion batteries. However, its further development is hindered by sluggish kinetics and fading capacity caused by volume expansion. Herein, a series of FeSe2 nanoparticles (NPs)-encapsulated carbon composites were successfully synthesized by tailoring the amount of Fe species through facile plasma engineering and followed by a simple selenization transformation process. Such a stable structure can effectively mitigate volume changes and accelerate kinetics, leading to excellent electrochemical performance. The optimized electrode (FeSe2@C2) exhibits outstanding reversible capacity of 853.1 mAh g−1 after 150 cycles and exceptional rate capacity of 444.9 mAh g−1 at 5.0 A g−1 for Li+ storage. In Na+ batteries, it possesses a relatively high capacity of 433.7 mAh g−1 at 0.1 A g−1 as well as good cycle stability. The plasma-engineered FeSe2@C2 composite, which profits from synergistic effect of small FeSe2 NPs and carbon framework with large specific surface area, exhibits remarkable ions/electrons transportation abilities during various kinetic analyses and unveils the energy storage mechanism dominated by surface-mediated capacitive behavior. This novel cost-efficient synthesis strategy might offer valuable guidance for developing transition metal-based composites towards energy storage materials.
Graphical abstract
硒化铁具有高容量和优异的化学特性,一直被认为是碱金属离子电池的理想阳极。然而,由于体积膨胀导致的动力学迟钝和容量衰减,阻碍了其进一步发展。在此,通过简便的等离子体工程技术调整铁物种的数量,再经过简单的硒化转化过程,成功合成了一系列 FeSe2 纳米粒子(NPs)-封装碳复合材料。这种稳定的结构可有效缓解体积变化并加速动力学过程,从而实现优异的电化学性能。优化后的电极(FeSe2@C2)在 150 次循环后显示出出色的可逆容量(853.1 mAh g-1),在 5.0 A g-1 的锂+存储条件下显示出卓越的速率容量(444.9 mAh g-1)。在 Na+ 电池中,它在 0.1 A g-1 时具有相对较高的 433.7 mAh g-1 容量和良好的循环稳定性。等离子体工程化的 FeSe2@C2 复合材料得益于小尺寸 FeSe2 NPs 和大比表面积碳骨架的协同效应,在各种动力学分析中表现出卓越的离子/电子传输能力,并揭示了以表面介导的电容行为为主导的储能机制。这种新型低成本合成策略可为开发过渡金属基复合材料储能材料提供有价值的指导。
{"title":"Plasma-engineered FeSe2-encapsulated carbon composites with enhanced kinetics for high-performance lithium and sodium ion batteries","authors":"Junmei Luo, Shufeng Bo, Seohyun Park, Beom-Kyeong Park, Oi Lun Li","doi":"10.1007/s42823-024-00771-9","DOIUrl":"https://doi.org/10.1007/s42823-024-00771-9","url":null,"abstract":"<p>Iron selenides with high capacity and excellent chemical properties have been considered as outstanding anodes for alkali metal-ion batteries. However, its further development is hindered by sluggish kinetics and fading capacity caused by volume expansion. Herein, a series of FeSe<sub>2</sub> nanoparticles (NPs)-encapsulated carbon composites were successfully synthesized by tailoring the amount of Fe species through facile plasma engineering and followed by a simple selenization transformation process. Such a stable structure can effectively mitigate volume changes and accelerate kinetics, leading to excellent electrochemical performance. The optimized electrode (FeSe<sub>2</sub>@C<sub><i>2</i></sub>) exhibits outstanding reversible capacity of 853.1 mAh g<sup>−1</sup> after 150 cycles and exceptional rate capacity of 444.9 mAh g<sup>−1</sup> at 5.0 A g<sup>−1</sup> for Li<sup>+</sup> storage. In Na<sup>+</sup> batteries, it possesses a relatively high capacity of 433.7 mAh g<sup>−1</sup> at 0.1 A g<sup>−1</sup> as well as good cycle stability. The plasma-engineered FeSe<sub>2</sub>@C<sub><i>2</i></sub> composite, which profits from synergistic effect of small FeSe<sub>2</sub> NPs and carbon framework with large specific surface area, exhibits remarkable ions/electrons transportation abilities during various kinetic analyses and unveils the energy storage mechanism dominated by surface-mediated capacitive behavior. This novel cost-efficient synthesis strategy might offer valuable guidance for developing transition metal-based composites towards energy storage materials.</p><h3 data-test=\"abstract-sub-heading\">Graphical abstract</h3>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141547159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Activated carbon is generally recognized as an applicable material for gas or liquid adsorption and electrochemical devices, such as electric double-layer capacitors (EDLCs). Owing to the continuous increase in its price, research aimed at discovering alternative materials and improving its fabrication yield is important. Herein, organic pigments were ingeniously employed to enhance the fabrication of high-surface-area activated carbon with remarkable efficiency. Moreover, the focus was centered on the assessment of activated carbon derived from 2,9-dimethylquinacridone, also known as CI Pigment Red 122 for its capacity to adsorb tetracycline (TC) and its applicability as an electrode material for EDLCs. Activating these organic pigments with varying potassium hydroxide ratios allowed the fabrication of activated carbon with a higher yield than that for conventional activated carbon. Furthermore, it was confirmed that activated carbon with a very high specific surface area can be efficiently fabricated, demonstrating a remarkable potential in various application fields. Notably, this activated carbon exhibited an impressive maximum specific surface area and a total pore volume of 3,935 m2/g and 2.324 cm3/g, respectively, showcasing its substantial surface area and distinctive porous characteristics. Additionally, the Langmuir and Freundlich isotherm models were employed to examine the TC adsorption on the activated carbon, with the Langmuir model demonstrating superior suitability than the Freundlich model. Furthermore, the electrochemical performance of an activated carbon-based electrode for EDLCs was rigorously evaluated through cyclic voltammetry. The specific capacitance exhibited a considerable increase in proportion to the expanding specific surface area of the activated carbon.
{"title":"Electrochemical and physical adsorption properties of activated carbon with ultrahigh specific surface area using 2,9-dimethyl quinacridone (2,9-DMQA)","authors":"Taemin Ahn, Woong Kwon, Byong Chol Bai, Euigyung Jeong","doi":"10.1007/s42823-024-00772-8","DOIUrl":"https://doi.org/10.1007/s42823-024-00772-8","url":null,"abstract":"<p>Activated carbon is generally recognized as an applicable material for gas or liquid adsorption and electrochemical devices, such as electric double-layer capacitors (EDLCs). Owing to the continuous increase in its price, research aimed at discovering alternative materials and improving its fabrication yield is important. Herein, organic pigments were ingeniously employed to enhance the fabrication of high-surface-area activated carbon with remarkable efficiency. Moreover, the focus was centered on the assessment of activated carbon derived from 2,9-dimethylquinacridone, also known as CI Pigment Red 122 for its capacity to adsorb tetracycline (TC) and its applicability as an electrode material for EDLCs. Activating these organic pigments with varying potassium hydroxide ratios allowed the fabrication of activated carbon with a higher yield than that for conventional activated carbon. Furthermore, it was confirmed that activated carbon with a very high specific surface area can be efficiently fabricated, demonstrating a remarkable potential in various application fields. Notably, this activated carbon exhibited an impressive maximum specific surface area and a total pore volume of 3,935 m<sup>2</sup>/g and 2.324 cm<sup>3</sup>/g, respectively, showcasing its substantial surface area and distinctive porous characteristics. Additionally, the Langmuir and Freundlich isotherm models were employed to examine the TC adsorption on the activated carbon, with the Langmuir model demonstrating superior suitability than the Freundlich model. Furthermore, the electrochemical performance of an activated carbon-based electrode for EDLCs was rigorously evaluated through cyclic voltammetry. The specific capacitance exhibited a considerable increase in proportion to the expanding specific surface area of the activated carbon.</p>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141547160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 : 2024-07-02DOI: 10.1007/s42823-024-00770-w
Gyumin Kim, Hong Jun Park, Sung Tae Jang, Bong Gill Choi
Despite the widespread use of polyaniline as a pseudocapacitor material, the cycling stability and rate capability of polyaniline-based electrodes are of concern because of the structural instability caused by repeated volumetric swelling and shrinking during the charge/discharge process. Herein, nanofiber-structured polyaniline was synthesized onto activated carbon textiles to ensure the long-term stability and high-rate capability of pseudocapacitors. The nanoporous structures of polyaniline nanofibers and activated textile substrate enhanced the ion and electron transfer during charge/discharge cycles. The resulting pseudocapacitor electrodes showed high gravimetric, areal, and volumetric capacitance of 769 F g−1, 2638 mF cm−2, and 845.9 F cm−3, respectively; fast charge/discharge capability of 92.6% capacitance retention at 55 mA cm−2; and good long-term stability of 97.6% capacitance retention over 2000 cycles. Moreover, a symmetric supercapacitor based on polyaniline nanofibers exhibited a high energy of 21.45 Wh cm−3 at a power density of 341.2 mW cm−3 in an aqueous electrolyte.
尽管聚苯胺作为一种伪电容器材料已被广泛使用,但由于在充放电过程中反复的体积膨胀和收缩会导致结构不稳定,因此聚苯胺基电极的循环稳定性和速率能力令人担忧。在此,我们在活性碳纺织品上合成了纳米纤维结构的聚苯胺,以确保伪电容器的长期稳定性和高速率能力。聚苯胺纳米纤维和活性纺织品基底的纳米多孔结构增强了充放电循环过程中的离子和电子转移。所制备的伪电容器电极具有较高的重力电容、面积电容和体积电容,分别为 769 F g-1、2638 mF cm-2 和 845.9 F cm-3;具有快速充放电能力,在 55 mA cm-2 时电容保持率为 92.6%;具有良好的长期稳定性,在 2000 次循环中电容保持率为 97.6%。此外,基于聚苯胺纳米纤维的对称超级电容器在水性电解液中的功率密度为 341.2 mW cm-3 时,能量高达 21.45 Wh cm-3。
{"title":"Deposition of polyaniline nanofibers on activated carbon textile for high-performance pseudocapacitors","authors":"Gyumin Kim, Hong Jun Park, Sung Tae Jang, Bong Gill Choi","doi":"10.1007/s42823-024-00770-w","DOIUrl":"https://doi.org/10.1007/s42823-024-00770-w","url":null,"abstract":"<p>Despite the widespread use of polyaniline as a pseudocapacitor material, the cycling stability and rate capability of polyaniline-based electrodes are of concern because of the structural instability caused by repeated volumetric swelling and shrinking during the charge/discharge process. Herein, nanofiber-structured polyaniline was synthesized onto activated carbon textiles to ensure the long-term stability and high-rate capability of pseudocapacitors. The nanoporous structures of polyaniline nanofibers and activated textile substrate enhanced the ion and electron transfer during charge/discharge cycles. The resulting pseudocapacitor electrodes showed high gravimetric, areal, and volumetric capacitance of 769 F g<sup>−1</sup>, 2638 mF cm<sup>−2</sup>, and 845.9 F cm<sup>−3</sup>, respectively; fast charge/discharge capability of 92.6% capacitance retention at 55 mA cm<sup>−2</sup>; and good long-term stability of 97.6% capacitance retention over 2000 cycles. Moreover, a symmetric supercapacitor based on polyaniline nanofibers exhibited a high energy of 21.45 Wh cm<sup>−3</sup> at a power density of 341.2 mW cm<sup>−3</sup> in an aqueous electrolyte.</p>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141522498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Volatile organic compounds (VOCs) are commonly produced in the combustion of fossil fuels and in chemical industries such as detergents and paints. VOCs in atmosphere cause different degrees of harm to human bodies and environments. Adsorption has become one of the most concerned methods to remove VOCs in atmosphere due to its high efficiency, simple operation and low energy consumption. Biomass-based porous carbon (BPC) has been considered as the most promising adsorption material because of the low cost and high absorption rate. In this paper, the key characteristic (e.g., specific surface area, pore structure, surface functional groups and basic composition) of BPC affecting the adsorption of VOCs in atmosphere were analyzed. The improvement of adsorption capacity of BPC by common modification methods, such as surface oxidation, surface reduction, surface loading and other modification methods, were discussed. Examples of BPC adsorption on different types of VOCs including aldehydes, ketones, aromatic VOCs, and halogenated hydrocarbons, were also reviewed. The specific adsorption mechanism was discussed. Finally, some unsolved problems and future research directions about BPC for adsorbing VOCs were propounded. This review can serve as a valuable reference for future developing effective biomass-based porous carbon VOCs adsorption technology.
{"title":"A review on the adsorption of volatile organic compounds by biomass-based porous carbon (BPC) and its mechanism","authors":"Haifan Yang, Guannan Liang, Xinyang Sun, Simiao Wu","doi":"10.1007/s42823-024-00766-6","DOIUrl":"https://doi.org/10.1007/s42823-024-00766-6","url":null,"abstract":"<p>Volatile organic compounds (VOCs) are commonly produced in the combustion of fossil fuels and in chemical industries such as detergents and paints. VOCs in atmosphere cause different degrees of harm to human bodies and environments. Adsorption has become one of the most concerned methods to remove VOCs in atmosphere due to its high efficiency, simple operation and low energy consumption. Biomass-based porous carbon (BPC) has been considered as the most promising adsorption material because of the low cost and high absorption rate. In this paper, the key characteristic (e.g., specific surface area, pore structure, surface functional groups and basic composition) of BPC affecting the adsorption of VOCs in atmosphere were analyzed. The improvement of adsorption capacity of BPC by common modification methods, such as surface oxidation, surface reduction, surface loading and other modification methods, were discussed. Examples of BPC adsorption on different types of VOCs including aldehydes, ketones, aromatic VOCs, and halogenated hydrocarbons, were also reviewed. The specific adsorption mechanism was discussed. Finally, some unsolved problems and future research directions about BPC for adsorbing VOCs were propounded. This review can serve as a valuable reference for future developing effective biomass-based porous carbon VOCs adsorption technology.</p>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141509305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Diamond/SiC composites were prepared by vacuum silica vapor-phase infiltration of in situ silicon–carbon reaction, and the thermophysical properties of the composites were modulated by controlling diamond graphitizing. The effects of diamond surface state and vacuum silicon infiltration temperature on diamond graphitization were investigated, and the micro-morphology, phase composition, and properties of the composites were observed and characterized. The results show that diamond pretreatment can reduce the probability of graphitizing; when the penetration temperature is greater than 1600 °C, the diamond undergoes a graphitizing phase transition and the micro-morphology presents a lamellar shape. The thermal conductivity, density, and flexural strength of the composites increased and then decreased with the increase of penetration temperature in the experimentally designed range of penetration temperature. The variation of thermal expansion coefficients of composites prepared with different penetration temperatures ranged from 0.8 to 3.0 ppm/K when the temperature was between 50 and 400 °C.
{"title":"Modulating the thermophysical properties of diamond/SiC composites via controlling the diamond graphitization","authors":"Xulei Wang, Yikang Li, Yabo Huang, Yalong Zhang, Pei Wang, Li Guan, Xinbo He, Rongjun Liu, Xuanhui Qu, Xiaoge Wu","doi":"10.1007/s42823-024-00767-5","DOIUrl":"https://doi.org/10.1007/s42823-024-00767-5","url":null,"abstract":"<p>Diamond/SiC composites were prepared by vacuum silica vapor-phase infiltration of in situ silicon–carbon reaction, and the thermophysical properties of the composites were modulated by controlling diamond graphitizing. The effects of diamond surface state and vacuum silicon infiltration temperature on diamond graphitization were investigated, and the micro-morphology, phase composition, and properties of the composites were observed and characterized. The results show that diamond pretreatment can reduce the probability of graphitizing; when the penetration temperature is greater than 1600 °C, the diamond undergoes a graphitizing phase transition and the micro-morphology presents a lamellar shape. The thermal conductivity, density, and flexural strength of the composites increased and then decreased with the increase of penetration temperature in the experimentally designed range of penetration temperature. The variation of thermal expansion coefficients of composites prepared with different penetration temperatures ranged from 0.8 to 3.0 ppm/K when the temperature was between 50 and 400 °C.</p>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141509307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nitrogen-doped carbon nanomaterials (N-CNMs) were prepared using Ni(NO3)2 as a catalyst in the laminar diffusion flame. Doping the structure of carbon nanomaterials (CNMs) with nitrogen can significantly change the characteristics of CNMs. The purpose of this research is to study the effect of adding ammonia (NH3) on the evolution of CNMs structure in the laminar flame of ethylene. Raman analysis shows that the intensity ratio (ID/IG) of the D-band and G-band of N-CNMs increases and then decreases after the addition of NH3. The intensity ratio is a maximum of 0.99, which has a good degree of disorder and defect density. The binding distribution of nitrogen was analyzed by X-ray photoelectron spectroscopy (XPS), and a correlation was found between the amount of nitrogen and the morphology of N-CNMs. Nitrogen atoms predominantly present in the forms of pyrrolic-N, pyridinic-N, graphitized-N and oxidized-N, with a doping ratio of nitrogen atoms reaching up to 2.44 at.%. This study found that smaller nickel (Ni) nanoparticles were the main catalysts for carbon nanotubes (CNTs), and their synthesis followed the ‘hollow growth mechanism’ and carbon nanofibers (CNFs) were synthesized from larger Ni nanoparticles according to the ‘solid growth mechanism’. Furthermore, a growth mechanism for the synthesis of bamboo-like CNTs using a specific particle size of the Ni catalyst is proposed. It is noteworthy that the synthesis and modulation of high-performance N-CNMs by flame method represents a simple and efficient approach.