Yes / In 1985, the serendipitous discovery of fullerene triggered the research of carbon structures into the world of symmetric nanomaterials. Consequently, Robert F. Curl, Harold W. Kroto and Richard E. Smalley were awarded the Noble prize in chemistry for their discovery of the buckminsterfullerene (C60 with a cage-like fused-ring structure). Fullerene, as the first symmetric nanostructure in carbon nanomaterials family, opened up new perspectives in nanomaterials field leading to discovery and research on other symmetric carbon nanomaterials like carbon nanotubes and two-dimensional graphene which put fullerenes in the shade, while fullerene as the most symmetrical molecule in the world with incredible properties deserves more attention in nanomaterials studies. Buckyball with its unique structure consisting of sp2 carbons which form a high symmetric cage with different sizes (C60, C70 and so on); however, the most abundant among them is C60 which possesses 60 carbon atoms. The combination of unique properties of this molecule extends its applications in divergent areas of science, especially those related to biomedical engineering. This review aims to be a comprehensive review with a broad interest to the biomedical engineering community, being a substantial overview of the most recent advances on fullerenes in biomedical applications that have not been exhaustively and critically reviewed in the past few years.

In recent years, the consequences of global warming have increased the discussion about the climate impact caused by humans and the fossil emissions. Sweden has decided to reduce the negative climate impact with a zero vision for the fossil carbon dioxide emissions in year 2045. In order to achieve this, great efforts and changes are needed both in the inhabitants' way of living but primarily in the base industry. The major cause is the use of fossil coal, which generates fossil carbon dioxide in the steel industry in particular. The fossil coal is added to the blast furnace in the steel process in forms of coke and coal, which reduces the iron and emits heat. The quality of the coke is important as it functions reducing agent, provides a mechanical support to the bed and enables the gas flow up through the blast furnace and enables dissolution of carbon in hot metal. Also, coke supplies energy from exothermic reactions between carbon and carbon dioxide that takes part in the blast furnace and the energy are further used for the heating and melting of the cold iron pellets. Due to these factors, the blast furnace process is dependent on coke for its function, which means that the entire process must be replaced if the steel production should work without fossil coal. However, there are many studies that have been done on how to replace some of the fossil coal with bio-coal, which is produced from biomass. If some of the fossil coal could be replaced by some bio-coal, this would mean that fossil carbon dioxide emissions would decrease and lead to a reduced climate impact. The process would still generate carbon dioxide, but on the other hand, a cycle would be formed because when biomass is grown, carbon dioxide is taken up, e.g. by the trees grown for this purpose. However, bio-coal does not have the same properties as fossil coal, which in turn affects the quality of the coke. Bio-coke is more reactive and more porous than fossil coke. In order to be able to replace fossil coke with bio-coke, it is likely necessary to pre-treat the biocoal before it replaces part of the fossil coal in the coke production. Bio-coal contains ash that acts as an internal catalyst. One theory is that if it is possible to produce a bio-coal with ash-free carbon structure, it can be used in the production of coke without having such a great effect on the coke quality. In this project, the ash's impact on the properties of bio-coal in coke was studied. Previous studies have shown that leaching is an effective method for removing ash from bio-coal. It can be leached in three different ways, either with water, weak acid or acid. However, it has been found that acid leaching has a certain impact on the carbon structure itself. For this reason, two types of bio-coal, torrefied Grot (forest residue) and torrefied sawdust were selected, which were leached both with water but also with weak acid in order to achieve an ash-reduced carbon structure. The acid selected was acetic acid, as it has been tested for similar purposes in previous studies. The leaching efficiency was evaluated by analysing the leachate with ICP-OES after leaching. According to the result, a significant part of the ash had been leached out, but the leaching with weak acid was much more effective than water leaching. To ensure that the carbon structure was not altered, light-optical microscopy was made which showed that the structure was intact. However, it was not possible to determine whether the pore sizes were changed after leaching and it is therefore relevant to investigate this further. Moreover, the leached II bio-coal replaced 5% of the fossil coal in the coal mixture for coke making. In addition to this, coke was also made with only the ash from the two bio-coals to see what effect the ash has on the coke quality. The result that was obtained from the TGA showed that the ash had a low impact on the reactivity of the coke. However, the coal structure of the coke had a great impact on the reactivity behaviour. Keywords: Bio-coke, bio-coal, leaching, ash, coke quality, carbon structures, torrefied sawdust

<p>Worldwide concern on fossil fuels depletion and adverse impact on environment pushed researchers to find an alternative energy source. Among various potential systems, electrochemical energy storage devices have attracted significant attraction due to short charge/discharge time, easy relocation, and relatively cheap cost compared to large storage systems. Much research has been reported to suggest a material for electrochemical storage systems. Carbon is a key part of human life in terms of energy source, building materials, daily clothing and foods. The extraordinary characteristics of carbon materials, including good conductivity, good structure stability, relatively low cost, and sustainability, draw interest to carbon application in energy storage systems. </p> <p>The introduction of lithium ion batteries (LIB), using graphite as an anode material, fulfilled the need of alternative energy source and elevated the technologies into next level high-performance applications such as portable devices. While the technology advancement in high performance electronics fosters the development of advanced lithium ion batteries, the introduction of electric vehicles and large intermittent systems seeks energy storage devices with high capacity, sustainability, and low cost. In this thesis, the impact of the characteristics of carbon material on energy storage system performance is studied. The work presented in this thesis not only suggests a cost-effective carbon synthesis for advanced LIB, but also addresses how the carbon structure impact and resolves the systematic issue associated with next generation energy storage systems.</p> <p>Chapter 3 describes a facile, one-step, solvent-free ‘dry autoclaving’ synthesis method utilizing coffee oil as the carbon precursor to obtain micrometer diameter spheroidal carbon particles for lithium ion battery anodes. The spheroidal morphology resulted from the evaporation of liquid oil into a liquid/gas phase interphase at elevated temperature (700 ^oC), followed by solid/gas sublimation interactions during cooling (below 350 ^oC) in a closed autoclave. A mechanism of spheroidal carbon formation is proposed considering the precursor’s composition and chemical interactions during autoclaving. The prepared carbon from dry autoclave has shown successful LIB performance and structure stability after 250 cycles.</p> <p>Chapter 4 illustrates the temperature effect on the structure of biomass derived carbon. In this study, due to its abundance and high porosity, pistachio shells were selected as the primary carbon source and carbonized at a range from 700 to 1500 °C. The temperature effect on carbon structure was analyzed by XRD, Raman, BET, and electron microscopy. To propose an advanced lithium ion battery, pistachio shell-derived carbon was applied as an anode material for a sodium ion battery (SIB). The correlation of carbon structure and SIB electrochemical performance is presented. Pistachio shell carbonized at 1000 °C resulted in highly amorphous structure with specific surface area (760.9 m²/g) and stable cycle performance (225 mAh g^-1 at 10 mA g^-1). With support from Raman, XRD, and BET, the storage mechanism has been studied as well.</p> <p> Chapter 5 describes the impact of carbon structure on resolving the polysulfide shuttling effect in lithium sulfur (Li-S) batteries. Lithium sulfur batteries have received tremendous attention due to its high theoretical capacity (1672 mAh g^-1), sulfur abundance, and low cost. However, main systemic issues, associated with polysulfide shuttling and low Coulombic efficiency, hinder the practical use of sulfur electrodes in commercial batteries. The work in this thesis demonstrated an effective strategy of decorating nano-MnO₂ (less than 10 wt. %) onto a sulfur reservoir in order to further capture the out-diffused polysulfides via chemical interaction, and thereby improve the electrochemical performance of sulfur electrodes without increasing the mass burden of the total battery configuration. Pistachio shell-derived sustainable carbon (PC) was employed as an effective sulfur container due to its structural characteristics (interconnected macro channels and micropores). With the aids of the structural benefits of PC scaffold and the uniform decoration of nano-MnO₂, the polysulfide shuttling effect was significantly suppressed and cycling performance of a sulfur cathode was dramatically improved over 250 cycles.</p> This thesis offers a new prospect in the study of carbon materials applications in various energy storage systems. This concept can be further extended to other applications, such as lithium metal batteries. The intercalation property of carbon structure can reduce the local current density, reducing the risk of lithium dendrite growth, which is the most critical issue of lithium metal battery.

Neste trabalho foi desenvolvido um procedimento experimental para a fabricação de estruturas 3D de nanotubos de carbono crescidos sobre substrato de cobre e decorados com partículas de óxido de titânio. Foram relacionados os três tipos diferentes de NTCs nesta estrutura (simples, dopados com nitrogênio e tratados com plasma) com a deposição do TiO2 por ALD. Foram igualmente propostas três aplicações para esta estrutura. A síntese dos NTCs verticalmente orientados, dopados e não dopados, foi otimizada dentre alguns parâmetros de síntese como temperatura, agente oxidante e principalmente, o filme catalisador. A introdução de defeitos nos NTCP através do tratamento a plasma oxidativo foi avaliada frente a variáveis como pressão, potência e tempo de exposição. A relação entre os defeitos destes três tipos de NTCs e a deposição de TiO2 por ALD foi avaliada por microscopia eletrônica de transmissão, Raman, XPS e TGA. O procedimento experimental para confecção da estrutura 3D foi desenvolvido etapa por etapa via diversas técnicas experimentais, desde caracterização química, imagem, até testes empíricos. Na estrutura final, foram avaliadas as propriedades fotocatalíticas pela decomposição de corante orgânico em meio aquoso, propriedades capacitivas por voltametria cíclica e propriedades de emissão por campo através de curvas de campo elétrico por corrente de emissão e diagramas F-N. Foram obtidas florestas de NTCs de boa qualidade com até 0.5mm de altura, de diâmetros e número de paredes regulares. Nestes foi possível introduzir defeitos de maneira controlável, mantendo o arranjo da floresta. As florestas de NTCNx alcançam uma altura de até 0,3mm com concentração de nitrogênio de 2% tendo os nanotubos uma estrutura típica “bamboo-like”. Os resultados mostram a relação entre o tipo de defeito e a deposição de TiO2 por ALD, obtendo-se partículas cristalinas para os NTCP e NTCNx, sendo neste ultimo as partículas homogeneamente distribuídas e com tamanho uniforme, enquanto nos NTCOx forma-se uma densa camada de TiO2 composta por grandes grãos monocristalinos A partir de processo como tratamentos térmicos e transferência dos NTC de substrato foi possível obter uma estrutura 3D composta de uma camada carbono grafítico e NTC-VAs sobre um substrato de cobre, sem alterar o arranjo inicial das florestas. As amostras mostraram efeito de emissão de elétrons por campo elétrico, porém estas requerem uma análise mais quantitativa. Os ensaios de fotocatálise mostraram que a imobilização do TiO2 em um suporte denso inviabiliza a degradação do corante em meio aquoso. Os NTCNx apresentaram maior capacitância que as mostras de NTCP, e o TiO2 foi aparentemente ineficaz para a melhoria desta propriedade. / In this work, we propose an experimental procedure for fabrication of 3D carbon nanotubes structures anchored with titanium oxide particles, on a copper substrate. We correlate three different types of CNTs from this structure (pristine, doped with nitrogen and treated with plasma) with the deposition of TiO2 by ALD. It was yet suggested, three applications for this structure. The synthesis of vertically aligned CNTs, doped and undoped, was optimized among several synthesis parameters such as temperature, oxidizing agent and specially, the catalyst film. The introduction of defects in NTCP by oxidative plasma treatment was evaluated against variables such as pressure, power and exposure time. The association between the defects from these three types of CNTs and the deposition of TiO2 by ALD was assessed by transmission microscopy, Raman, XPS and TGA. The experimental procedure for assembling the 3D structure had been studied step by step by various techniques, from chemical and imaging, up to empirical testing. In the final structure, the photocatalytic properties were evaluated by the organic dye decomposition in an aqueous medium, capacitive properties by cyclic voltammetry and field emission properties through electric field versus emission current curves and F-N diagram. Was obtained high quality NTCs with a height up to 0.5mm with regular diameters and number of walls. On these, it was introduced, in a controllable way, a high amount of defects without jeopardizing the forest structure. The NTCNx forest reach a 0,3nm height with a 2% nitrogen concentration in its typical structure “bamboo-like”. The results show the relation between the type of defect and the deposition of TiO2 by ALD, forming crystalline particles over the NTCP and NTCNx, in this last evenly distributed with uniform size, while on the NTCOx is is formed a dense TiO2 layer shaped by large monocrystalline grains. By process such as heat treatments and CNT transferring was achieved a 3d structure composed by a graphitic carbon layer and VACNTs over a cupper substrate, without disturb the forest assembly. The samples showed electron field emission effect, but its assessment for quantitative analysis was limited to technical issues. The photocatalysis tests showed that immobilization of TiO2 on a dense support prevents the dye degradation in an aqueous medium. The NTCNx shown higher capacitance than NTCP, and the TiO2 was apparently ineffective for improvement of this property.

Neste trabalho foi desenvolvido um procedimento experimental para a fabricação de estruturas 3D de nanotubos de carbono crescidos sobre substrato de cobre e decorados com partículas de óxido de titânio. Foram relacionados os três tipos diferentes de NTCs nesta estrutura (simples, dopados com nitrogênio e tratados com plasma) com a deposição do TiO2 por ALD. Foram igualmente propostas três aplicações para esta estrutura. A síntese dos NTCs verticalmente orientados, dopados e não dopados, foi otimizada dentre alguns parâmetros de síntese como temperatura, agente oxidante e principalmente, o filme catalisador. A introdução de defeitos nos NTCP através do tratamento a plasma oxidativo foi avaliada frente a variáveis como pressão, potência e tempo de exposição. A relação entre os defeitos destes três tipos de NTCs e a deposição de TiO2 por ALD foi avaliada por microscopia eletrônica de transmissão, Raman, XPS e TGA. O procedimento experimental para confecção da estrutura 3D foi desenvolvido etapa por etapa via diversas técnicas experimentais, desde caracterização química, imagem, até testes empíricos. Na estrutura final, foram avaliadas as propriedades fotocatalíticas pela decomposição de corante orgânico em meio aquoso, propriedades capacitivas por voltametria cíclica e propriedades de emissão por campo através de curvas de campo elétrico por corrente de emissão e diagramas F-N. Foram obtidas florestas de NTCs de boa qualidade com até 0.5mm de altura, de diâmetros e número de paredes regulares. Nestes foi possível introduzir defeitos de maneira controlável, mantendo o arranjo da floresta. As florestas de NTCNx alcançam uma altura de até 0,3mm com concentração de nitrogênio de 2% tendo os nanotubos uma estrutura típica “bamboo-like”. Os resultados mostram a relação entre o tipo de defeito e a deposição de TiO2 por ALD, obtendo-se partículas cristalinas para os NTCP e NTCNx, sendo neste ultimo as partículas homogeneamente distribuídas e com tamanho uniforme, enquanto nos NTCOx forma-se uma densa camada de TiO2 composta por grandes grãos monocristalinos A partir de processo como tratamentos térmicos e transferência dos NTC de substrato foi possível obter uma estrutura 3D composta de uma camada carbono grafítico e NTC-VAs sobre um substrato de cobre, sem alterar o arranjo inicial das florestas. As amostras mostraram efeito de emissão de elétrons por campo elétrico, porém estas requerem uma análise mais quantitativa. Os ensaios de fotocatálise mostraram que a imobilização do TiO2 em um suporte denso inviabiliza a degradação do corante em meio aquoso. Os NTCNx apresentaram maior capacitância que as mostras de NTCP, e o TiO2 foi aparentemente ineficaz para a melhoria desta propriedade. / In this work, we propose an experimental procedure for fabrication of 3D carbon nanotubes structures anchored with titanium oxide particles, on a copper substrate. We correlate three different types of CNTs from this structure (pristine, doped with nitrogen and treated with plasma) with the deposition of TiO2 by ALD. It was yet suggested, three applications for this structure. The synthesis of vertically aligned CNTs, doped and undoped, was optimized among several synthesis parameters such as temperature, oxidizing agent and specially, the catalyst film. The introduction of defects in NTCP by oxidative plasma treatment was evaluated against variables such as pressure, power and exposure time. The association between the defects from these three types of CNTs and the deposition of TiO2 by ALD was assessed by transmission microscopy, Raman, XPS and TGA. The experimental procedure for assembling the 3D structure had been studied step by step by various techniques, from chemical and imaging, up to empirical testing. In the final structure, the photocatalytic properties were evaluated by the organic dye decomposition in an aqueous medium, capacitive properties by cyclic voltammetry and field emission properties through electric field versus emission current curves and F-N diagram. Was obtained high quality NTCs with a height up to 0.5mm with regular diameters and number of walls. On these, it was introduced, in a controllable way, a high amount of defects without jeopardizing the forest structure. The NTCNx forest reach a 0,3nm height with a 2% nitrogen concentration in its typical structure “bamboo-like”. The results show the relation between the type of defect and the deposition of TiO2 by ALD, forming crystalline particles over the NTCP and NTCNx, in this last evenly distributed with uniform size, while on the NTCOx is is formed a dense TiO2 layer shaped by large monocrystalline grains. By process such as heat treatments and CNT transferring was achieved a 3d structure composed by a graphitic carbon layer and VACNTs over a cupper substrate, without disturb the forest assembly. The samples showed electron field emission effect, but its assessment for quantitative analysis was limited to technical issues. The photocatalysis tests showed that immobilization of TiO2 on a dense support prevents the dye degradation in an aqueous medium. The NTCNx shown higher capacitance than NTCP, and the TiO2 was apparently ineffective for improvement of this property.

Neste trabalho foi desenvolvido um procedimento experimental para a fabricação de estruturas 3D de nanotubos de carbono crescidos sobre substrato de cobre e decorados com partículas de óxido de titânio. Foram relacionados os três tipos diferentes de NTCs nesta estrutura (simples, dopados com nitrogênio e tratados com plasma) com a deposição do TiO2 por ALD. Foram igualmente propostas três aplicações para esta estrutura. A síntese dos NTCs verticalmente orientados, dopados e não dopados, foi otimizada dentre alguns parâmetros de síntese como temperatura, agente oxidante e principalmente, o filme catalisador. A introdução de defeitos nos NTCP através do tratamento a plasma oxidativo foi avaliada frente a variáveis como pressão, potência e tempo de exposição. A relação entre os defeitos destes três tipos de NTCs e a deposição de TiO2 por ALD foi avaliada por microscopia eletrônica de transmissão, Raman, XPS e TGA. O procedimento experimental para confecção da estrutura 3D foi desenvolvido etapa por etapa via diversas técnicas experimentais, desde caracterização química, imagem, até testes empíricos. Na estrutura final, foram avaliadas as propriedades fotocatalíticas pela decomposição de corante orgânico em meio aquoso, propriedades capacitivas por voltametria cíclica e propriedades de emissão por campo através de curvas de campo elétrico por corrente de emissão e diagramas F-N. Foram obtidas florestas de NTCs de boa qualidade com até 0.5mm de altura, de diâmetros e número de paredes regulares. Nestes foi possível introduzir defeitos de maneira controlável, mantendo o arranjo da floresta. As florestas de NTCNx alcançam uma altura de até 0,3mm com concentração de nitrogênio de 2% tendo os nanotubos uma estrutura típica “bamboo-like”. Os resultados mostram a relação entre o tipo de defeito e a deposição de TiO2 por ALD, obtendo-se partículas cristalinas para os NTCP e NTCNx, sendo neste ultimo as partículas homogeneamente distribuídas e com tamanho uniforme, enquanto nos NTCOx forma-se uma densa camada de TiO2 composta por grandes grãos monocristalinos A partir de processo como tratamentos térmicos e transferência dos NTC de substrato foi possível obter uma estrutura 3D composta de uma camada carbono grafítico e NTC-VAs sobre um substrato de cobre, sem alterar o arranjo inicial das florestas. As amostras mostraram efeito de emissão de elétrons por campo elétrico, porém estas requerem uma análise mais quantitativa. Os ensaios de fotocatálise mostraram que a imobilização do TiO2 em um suporte denso inviabiliza a degradação do corante em meio aquoso. Os NTCNx apresentaram maior capacitância que as mostras de NTCP, e o TiO2 foi aparentemente ineficaz para a melhoria desta propriedade. / In this work, we propose an experimental procedure for fabrication of 3D carbon nanotubes structures anchored with titanium oxide particles, on a copper substrate. We correlate three different types of CNTs from this structure (pristine, doped with nitrogen and treated with plasma) with the deposition of TiO2 by ALD. It was yet suggested, three applications for this structure. The synthesis of vertically aligned CNTs, doped and undoped, was optimized among several synthesis parameters such as temperature, oxidizing agent and specially, the catalyst film. The introduction of defects in NTCP by oxidative plasma treatment was evaluated against variables such as pressure, power and exposure time. The association between the defects from these three types of CNTs and the deposition of TiO2 by ALD was assessed by transmission microscopy, Raman, XPS and TGA. The experimental procedure for assembling the 3D structure had been studied step by step by various techniques, from chemical and imaging, up to empirical testing. In the final structure, the photocatalytic properties were evaluated by the organic dye decomposition in an aqueous medium, capacitive properties by cyclic voltammetry and field emission properties through electric field versus emission current curves and F-N diagram. Was obtained high quality NTCs with a height up to 0.5mm with regular diameters and number of walls. On these, it was introduced, in a controllable way, a high amount of defects without jeopardizing the forest structure. The NTCNx forest reach a 0,3nm height with a 2% nitrogen concentration in its typical structure “bamboo-like”. The results show the relation between the type of defect and the deposition of TiO2 by ALD, forming crystalline particles over the NTCP and NTCNx, in this last evenly distributed with uniform size, while on the NTCOx is is formed a dense TiO2 layer shaped by large monocrystalline grains. By process such as heat treatments and CNT transferring was achieved a 3d structure composed by a graphitic carbon layer and VACNTs over a cupper substrate, without disturb the forest assembly. The samples showed electron field emission effect, but its assessment for quantitative analysis was limited to technical issues. The photocatalysis tests showed that immobilization of TiO2 on a dense support prevents the dye degradation in an aqueous medium. The NTCNx shown higher capacitance than NTCP, and the TiO2 was apparently ineffective for improvement of this property.

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