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Aerosol-assisted chemical vapor deposition (AACVD) was used to deposit highly transparent and conductive titanium or fluorine-doped and titanium-fluorine co-doped ZnO thin films on glass substrate at 450 °C. All films were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), UV-Vis spectroscopy, scanning electron spectroscopy (SEM), and four-point probe. The films were 600-680â nm thick, crystalline, and highly transparent (80-87 %). The co-doped film consisted of 0.70â at % titanium and 1â at % fluorine, and displayed a charger carrier mobility, charge carrier concentration, and a minimum resistivity of 8.4â cm2â V-1 s-1, 3.97×1020â cm-3, and 1.69×10-3â Ω cm, respectively. A band gap of 3.6â eV was observed for the co-doped film. Compared to the undoped and singly doped films, the co-doped film displayed a notably higher structure morphology (more homogenous grains with well-defined boundaries) suitable for transparent conducting oxide applications.
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Solar power represents an abundant and readily available source of renewable energy. However, its intermittent nature necessitates external energy storage solutions, which can often be expensive, bulky, and associated with energy conversion losses. This study introduces the concept of a photo-accelerated battery that seamlessly integrates energy harvesting and storage functions within a single device. In this research, a novel approach for crafting photocathodes is presented using hydrogenated vanadium pentoxide (H:V2O5) nanofibers. This method enhances optical activity, electronic conductivity, and ion diffusion rates within photo-accelerated Li-ion batteries. This study findings reveal that H:V2O5 exhibits notable improvements in specific capacity under both dark and illuminated conditions. Furthermore, it demonstrates enhanced diffusion kinetics and charge storage performance when exposed to light, as compared to pristine counterparts. This strategy of defect engineering holds great promise for the development of high-performance photocathodes in future energy storage applications.
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Zinc metal is a promising candidate for anodes in zinc-ion batteries (ZIBs), but its widespread implementation is hindered by dendrite growth in aqueous electrolytes. Dendrites lead to undesirable side reactions, such as hydrogen evolution, passivation, and corrosion, causing reduced capacity during prolonged cycling. In this study, an approach is explored to address this challenge by directly growing 1D zinc oxide (ZnO) nanorods (NRs) and 2D ZnO nanoflakes (NFs) on Zn anodes, forming artificial layers to enhance ZIB performance. The incorporation of ZnO on the anode offers both chemical and thermal stability and leverages its n-type semiconductor nature to facilitate the formation of ohmic contacts. This results in efficient electron transport during Zn ion plating and stripping processes. Consequently, the ZnO NFs-coated Zn anodes demonstrate significantly improved charge storage performance, achieving 348 mAh g-1 , as compared to ZnO NRs (250 mAh g-1 ) and pristine Zn (160 mAh g-1 ) anodes when evaluated in full cells with V2 O5 cathodes. One significant advantage of ZnO NFs lies in their highly polar surfaces, promoting strong interactions with water molecules and rendering them exceptionally hydrophilic. This characteristic enhances the ability of ZnO NFs to desolvate Zn2+ ions, leading to improved charge storage performance.
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Herein, ammonium fluoride is reported as an additive within 1 M ZnSO4 aqueous electrolyte to improve zinc anodes. The as-formed electrostatic shielding layer and ZnF2-rich solid-state interphase layer can jointly inhibit side reactions and dendrite growth. Consequently, symmetric ZnâZn cells, asymmetric ZnâCu cells and ZnâMnO2 cells with the additives present dramatically enhanced performance in comparison to the ones with pure ZnSO4 electrolyte counterparts. This work proposes a facile but effective method to achieve highly reversible zinc anodes.
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The search for efficient materials for sustainable infrastructure is an urgent challenge toward potential negative emission technologies and the global environmental crisis. Pleasant, efficient sunlight-activated coatings for applications in self-cleaning windows are sought in the glass industry, particularly those produced from scalable technologies. The current work presents visible-light-active iodide-doped BiOBr thin films fabricated using aerosol-assisted chemical vapor deposition. The impact of dopant concentration on the structural, morphological, and optical properties was studied systematically. The photocatalytic properties of the parent materials and as-deposited doped films were evaluated using the smart ink test. An optimized material was identified as containing 2.7 atom % iodide dopant. Insight into the photocatalytic behavior of these coatings was gathered from photoluminescence and photoelectrochemical studies. The optimum photocatalytic performance could be explained from a balance between photon absorption, charge generation, carrier separation, and charge transport properties under 450 nm irradiation. This optimized iodide-doped BiOBr coating is an excellent candidate for the photodegradation of volatile organic pollutants, with potential applications in self-cleaning windows and other surfaces.
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INTRODUCTION AND OBJECTIVE: Individuals who are not professional and competitive athletes but who engage in regular (even daily) physical activity may experience a different body image in the context of physical activity compared with that in everyday life. The Contextual Body Image Questionnaire for Athletes (CBIQA) has been developed to assess aspects of body image within these two dimensions, but has not yet been validated in the Polish population. This study aimed to conduct a cross-cultural adaptation of the CBIQA for physically active Polish adults. MATERIAL AND METHODS: The study sample comprised 90 young Polish adults (49 women and 41 men). All respondents regularly participated in recreational sports. The average age of the sample was 21.4 years. All participants engaged in physical activity at least 3 times per week. The average training experience was 8.6 years. A 3-phase study was conducted: 1) translation of the CBIQA for use in a Polish sample, 2) pretesting and cognitive debriefing, and 3) evaluation of the test-retest reliability. The test-retest interval was 7 days. Interclass correlation coefficients were calculated. RESULTS: The 1-week test- retest results (ICC) ranged from 0.83-0.94 in the daily life subscales and from 0.86-0.95 in the athletic subscales among all participants. The reliability of the CBIQA was high. The alpha value for the internal consistency of the translated and adapted instrument was 0.91. After the translation and cognitive interview, 3 sentences were reworded to adapt the instrument to Polish culture. CONCLUSIONS: The CBIQA exhibited a high tes-retest reliability and good validity for assessing daily and physical activity-related body image in a Polish population.
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Imagem Corporal , Comparação Transcultural , Masculino , Humanos , Adulto , Feminino , Adulto Jovem , Polônia , Reprodutibilidade dos Testes , Inquéritos e Questionários , Atletas , PsicometriaRESUMO
The Body Appreciation Scale-2 (BAS-2) is a widely used measure of a core facet of the positive body image construct. However, extant research concerning measurement invariance of the BAS-2 across a large number of nations remains limited. Here, we utilised the Body Image in Nature (BINS) dataset - with data collected between 2020 and 2022 - to assess measurement invariance of the BAS-2 across 65 nations, 40 languages, gender identities, and age groups. Multi-group confirmatory factor analysis indicated that full scalar invariance was upheld across all nations, languages, gender identities, and age groups, suggesting that the unidimensional BAS-2 model has widespread applicability. There were large differences across nations and languages in latent body appreciation, while differences across gender identities and age groups were negligible-to-small. Additionally, greater body appreciation was significantly associated with higher life satisfaction, being single (versus being married or in a committed relationship), and greater rurality (versus urbanicity). Across a subset of nations where nation-level data were available, greater body appreciation was also significantly associated with greater cultural distance from the United States and greater relative income inequality. These findings suggest that the BAS-2 likely captures a near-universal conceptualisation of the body appreciation construct, which should facilitate further cross-cultural research.
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Imagem Corporal , Identidade de Gênero , Humanos , Imagem Corporal/psicologia , Psicometria , Reprodutibilidade dos Testes , Análise Fatorial , Idioma , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Eating disorders negatively influence athletes' health and performance. To achieve a high level of performance and conform to cultural expectations regarding an athletic body type, female athletes often restrict their diets, which can lead to eating disorders. In addition to factors related to the sports environment, adolescent athletes are subject to changes caused by the maturation process. Therefore, the same factors may have different effects on eating disorder risk among adolescent and adult athletes. This study examined the relationship between eating disorder risk, specific aspects of the sports environment (sport type, level of competition [national and international], and training background), and individual aspects (body satisfaction and body mass index) in two groups of athletes: adolescents and adults. METHODS: The sample included 241 highly trained female athletes aged 12-30 years (M = 20.68, SD = 4.45) recruited from different sports clubs in Poland. The subgroup of adolescents consisted of 82 athletes, while the number of adult athletes was 159. The Eating Attitudes Test questionnaire was used to assess the eating disorder risk among the athletes. Body satisfaction was measured using the Feelings and Attitudes Toward Body Scale incorporated into the Body Investment Scale. RESULTS: Eating disorder risk was prevalent among 14.6% of the adolescent and 6.9% of the adult athletes. Significant associations between eating disorder risk and the studied variables were noted only among adolescent athletes. Univariate logistic regression analysis revealed that the occurrence of eating disorder risk was associated with participation in lean non-aesthetic sports (OR = 11.50, 95% CI: 3.58-37.09). Moreover, eating disorder risk was associated with athletes' lower body satisfaction (OR = 0.80, 95% CI: 0.70-0.92). Body mass index was not included in the final regression model. CONCLUSIONS: The study indicated that eating disorder risk in adolescent female athletes was related to sport type and body satisfaction. The findings showed that, in adolescent athletes, eating disorder risk was the most associated with practicing lean non-aesthetic sports. Coaches and athletes should be aware that eating disorder risk increases among individuals with a lower body image.
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Detecting low dose rates of X-rays is critical for making safer radiology instruments, but is limited by the absorber materials available. Here, we develop bismuth oxyiodide (BiOI) single crystals into effective X-ray detectors. BiOI features complex lattice dynamics, owing to the ionic character of the lattice and weak van der Waals interactions between layers. Through use of ultrafast spectroscopy, first-principles computations and detailed optical and structural characterisation, we show that photoexcited charge-carriers in BiOI couple to intralayer breathing phonon modes, forming large polarons, thus enabling longer drift lengths for the photoexcited carriers than would be expected if self-trapping occurred. This, combined with the low and stable dark currents and high linear X-ray attenuation coefficients, leads to strong detector performance. High sensitivities reaching 1.1 × 103 µC Gyair-1 cm-2 are achieved, and the lowest dose rate directly measured by the detectors was 22 nGyair s-1. The photophysical principles discussed herein offer new design avenues for novel materials with heavy elements and low-dimensional electronic structures for (opto)electronic applications.
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The development of photo-enhanced lithium-ion batteries, where exposing the electrodes to light results in higher capacities, higher rate performance or self-charging, has recently gained substantial traction. The challenge in these devices lies in the realisation of photo-electrodes with good optical and electrochemical properties. Herein, we propose copper-hexahydroxybenzene as the active photo-electrode material which both harvests light and stores energy. This material was mixed with reduced graphene oxide as a conductive additive and charge transfer medium to create photo-active electrodes. Under illumination, these electrodes show improved charge storage kinetics resulting in the photo-accelerated charging and discharging performance (i.e. specific capacities improvement from 107 mA h g-1 to 126 mA h g-1 at 200 mA g-1 and 79 mA h g-1 to 97 mA h g-1 at 2000 mA g-1 under 1 sun illumination as compared to dark).
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Physical education is a space in which adolescents may become the victims or perpetrators of bullying. The aim of this study was to evaluate the relationship between being a victim or perpetrator of physical, verbal, or social bullying in physical education, and peer support, gender, weight status, and age. The sample consisted of 2, 848 adolescents (1, 512 girls and 1, 336 boys) aged 14-16 from Poland. The participants' body mass index was determined based on their measured height and weight. The Health Behaviour in School-Aged Children questionnaire was used to assess whether the participants were victims or perpetrators of bullying. Peer support during physical education was assessed using the modified Teacher and Classmate Support Scale. The analysis of logistic regressions revealed that low peer support increased the probability of being the victim of physical, verbal, and social bullying (odds ratio [OR], 1.58-2.91) and becoming a perpetrator of bullying (OR, 1.14-1.37) in physical education. Additionally, being overweight increased the likelihood of being a verbal victim (OR, 1.39) and being obese raised the probability of becoming social victim (OR, 1.60). Boys more often experienced (OR, 1.12-2.06) and caused bullying (OR, 1.25-1.89) than girls. Moreover, victims were mainly younger (14-year-old) students (OR, 1.16-1.21), while perpetrators were more often older (15- and 16-year-old) adolescents (OR, 1.12-1.20). This research indicated that peer support can play a key role in preventing bullying in physical education. Physical education teachers should pay special attention to unpopular and rejected students because they most often become the victims and perpetrators of bullying. Creating a climate that fosters the development of high peer support might protect adolescents from becoming a victim-and a perpetrator-of bullying in physical education.
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Bullying , Vítimas de Crime , Adolescente , Criança , Feminino , Humanos , Masculino , Educação Física e Treinamento , Polônia , EstudantesRESUMO
INTRODUCTION AND OBJECTIVE: Systematic monitoring of physical activity of young populations from different regions may be useful for making international comparisons, better understanding trends in physical activity and designing public health interventions to increase physical activity. Thus, the aim of the study was to comprehensively review studies examining the level of physical activity of children and adolescents from the Visegrád countries, and indicate the percentage of children and adolescents meeting the recommended level of physical activity. MATERIAL AND METHODS: A systematic search of the published literature was conducted. Included were reports with original research that consisted of the proportion of children and adolescents who met physical activity recommendations or guidelines. To provide a current picture of physical activity of children and adolescents, the review was restricted to studies published between January 2015 - November 2018. RESULTS: Moderate-to-vigorous physical activity recommendations were met by between 7.5% - 69.4% of children and adolescents. Vigorous physical activity recommendations were met by between 33.6% - 64.5% of children and adolescents. Daily recommendations for the number of steps taken were fulfilled by between 11.6% - 69.0% of children and adolescents. Differences between age categories, genders and countries were observed. CONCLUSIONS: Public health interventions to increase physical activity are required to decrease insufficient levels of physical activity in children and adolescents, especially in girls. The review also highlights the need for studies with representative random samples that use validated measurement methods.
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Exercício Físico , Adolescente , Saúde do Adolescente , Criança , Saúde da Criança , Pré-Escolar , República Tcheca , Feminino , Humanos , Hungria , Masculino , Polônia , EslováquiaRESUMO
Diodes fabricated using a blend of poly(3-hexylthiophene) and phenyl-C61-butyric acid methyl ester (6-80 µm thick) as an organic semiconductor component achieved consistent 4 MeV α particle detection. Current-voltage characteristics and current-time measurements were obtained under α irradiation and in its absence. Steady-state and transient (time-of-flight) photoconduction measurements were additionally performed. Low-bias (<20 V) α particle detection gain-efficiency products of order 10-2 were measured. The α particle detection was achieved reproducibly, reversibly, and repeatably in different devices of varying organic semiconductor layer thicknesses using both the steady-state and time-dependent (dynamic) diode responses. Conductive gain, due to trapped electrons, increased the α particle gain-efficiency product in both forward and reverse bias conditions as well as increasing steady-state photoconduction. The device thickness was optimized to maximize the gain-efficiency product by matching the penetration depth of the α particle, obtained by modeling, to the organic semiconductor layer thickness. Very high confidence α particle detection was achieved (with signal-to-noise ratios exceeding 20) under optimized device dimensions and drive conditions. Hecht function fitting of the gain-efficiency product versus electric field data returns mobility-lifetime products of order 10-6-10-7 cm2 V-1. This work demonstrates that solution-processed organic semiconductor diodes are viable for low-voltage α particle detection.
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In this study, both memcapacitive and memristive characteristics in the composite material based on the rhenium disulfide (ReS2) rich in rhenium (VI) oxide (ReO3) surface overlayer (ReO3@ReS2) and in the indium tin oxide (ITO)/ReO3@ReS2/aluminum (Al) device configuration is presented. Comprehensive experimental analysis of the ReO3@ReS2 material properties' dependence on the memcapacitor electrical characteristics was carried out by standard as well as frequency-dependent current-voltage, capacitance-voltage, and conductance-voltage studies. Furthermore, determination of the charge carrier conduction model, charge carrier mobility, density of the trap states, density of the available charge carrier, free-carrier concentration, effective density of states in the conduction band, activation energy of the carrier transport, as well as ion hopping was successfully conducted for the ReO3@ReS2 based on the experimental data. The ITO/ReO3@ReS2/Al charge carrier conduction was found to rely on the mixed electronic-ionic processes, involving electrochemical metallization and lattice oxygen atoms migration in response to the externally modulated electric field strength. The chemical potential generated by the electronic-ionic ITO/ReO3@ReS2/Al resistive memory cell non-equlibrium processes leads to the occurrence of the nanobattery effect. This finding supports the possibility of a nonvolatile memory cell with a new operation principle based on the potential read function.
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The Breast Size Satisfaction Survey (BSSS) was established to assess women's breast size dissatisfaction and breasted experiences from a cross-national perspective. A total of 18,541 women were recruited from 61 research sites across 40 nations and completed measures of current-ideal breast size discrepancy, as well as measures of theorised antecedents (personality, Western and local media exposure, and proxies of socioeconomic status) and outcomes (weight and appearance dissatisfaction, breast awareness, and psychological well-being). In the total dataset, 47.5 % of women wanted larger breasts than they currently had, 23.2 % wanted smaller breasts, and 29.3 % were satisfied with their current breast size. There were significant cross-national differences in mean ideal breast size and absolute breast size dissatisfaction, but effect sizes were small (η2â¯=â¯.02-.03). The results of multilevel modelling showed that greater Neuroticism, lower Conscientiousness, lower Western media exposure, greater local media exposure, lower financial security, and younger age were associated with greater breast size dissatisfaction across nations. In addition, greater absolute breast size dissatisfaction was associated with greater weight and appearance dissatisfaction, poorer breast awareness, and poorer psychological well-being across nations. These results indicate that breast size dissatisfaction is a global public health concern linked to women's psychological and physical well-being.
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Insatisfação Corporal/psicologia , Mama , Saúde Global , Satisfação Pessoal , Adulto , Feminino , Humanos , Tamanho do ÓrgãoRESUMO
Nanoparticles (NPs) have had increasingly successful applications including in emissive or photovoltaic devices; however, trap states associated with the surface of NPs often drastically reduce the efficiency of devices and are difficult to detect spectroscopically. We show the applicability of photoconduction as the means of detecting and quantifying trap states in NPs. We performed time-of-flight (ToF) photoconduction measurements, using semiconducting poly[bis(4-phenyl)(4-butyphenyl)amine] (P-TPD) doped with either core/shell CdSeS/CdS quantum dots (QDs) or perovskite CsPbBr3 NPs, both of which are carefully designed to be energetically matched. In the case of the QDs, a drop in the hole mobility from â¼10-3 to â¼10-4 cm2 V-1 s-1 was observed when compared to a control sample, suggesting the presence of a hole trapping. These trap states were found to be around -5.0 to -4.9 eV from the vacuum level. The presence of the trap states was further supported by a coincident reduction in the photoluminescence (PL), quantum yield (QY), and lifetime of the core/shell QDs after purification. Using the measured reductions in the PL, QY, and lifetime, the surface trap state density was estimated to increase by between 20 and 40%, most likely due to a ligand detachment. In the case of the perovskite NP-doped samples, a mobility of â¼10-3 cm2 V-1 s-1 was measured. Thus, doping with perovskite NPs did not generate any obvious hole trapping from the P-TPD matrix. The absence of a trapping may be related to the reduced surface-to-volume ratio and NP number density of the perovskite NPs compared to the core/shell QDs, since the perovskite NPs are approximately 10 times larger in radius than that of the core/shell QDs. Our results suggest that to minimize the presence of trap states with a view to improving device performance, large-size perovskite NPs appear to be better than small-size QDs.
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The recent emergence of nanotechnology has provided a new therapeutic modality in case of silver nanoparticles. Dressings containing silver form the basis for the treatment of burns and wounds, either acute or chronic ones. The aim of the study was to examine silver release from the different wound dressings: commercially available (Atrauman Ag, Aquacel Ag) and experimental (FKDP-AgNPs) using MEKC. In order to characterize prepared keratin based wound dressing before and after its modification with AgNPs, a compositional analysis was conducted using energy dispersive X-ray spectroscopy. Nanosilver toxicity was evaluated with the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4 sulfophenyl)-2H-tetrazolium test. Silver release from wound dressings was assessed using MEKC. The best separation was observed for MEKC in 20 mM borate buffer at pH 9 with 20 mM SDS addition. In vitro studies showed silver at higher concentration than 10 ppm exerted a toxic effect on fibroblasts isolated from diabetic mice versus. NIH/3T3 and BJ cell lines (p < 0.05). We observed silver was released more gradually from experimental FKDP-AgNPs wound dressing, in compare to commercially available wound dressings. The fast and low-cost method utilizing MEKC can be used in clinical practice to detect silver release from the wound dressings.
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Bandagens/normas , Cromatografia Capilar Eletrocinética Micelar/métodos , Nanopartículas Metálicas/análise , Prata/análise , Animais , Queimaduras/terapia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Camundongos , Prata/toxicidade , Ferimentos e Lesões/terapiaRESUMO
BACKGROUND: The aim of this study was to evaluate the relationship between the motives for undertaking physical activity (PA) and the intensity of PA in Polish adolescents. METHODS: The study included 1,231 students, 515 boys (age 16.2 ± 0.7 years) and 716 girls (age 16.3 ± 0.6 years). The participants were recruited from secondary schools in 20 conurbations throughout Poland. The International Physical Activity Questionnaire-Long Form and the Motives for Physical Activity Measure-Revised were used. RESULTS: In boys, all motives predicted a 10.4% variance in vigorous intensity of PA (F(5, 509) = 11.822, p < .001). Higher scores on competence and appearance motives for PA were found to be predictors of higher level of vigorous intensity of PA. In girls, all motives explained a 7.4% variance in vigorous intensity of PA (F(5, 710) = 11.292, p < .001). Higher scores on competence and appearance motives for PA were found to be predictors of higher level of vigorous intensity of PA. CONCLUSIONS: This study shows that competence and appearance related motives for PA are important motivations for Polish adolescent girls and boys in undertaking vigorous intensity PA.
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Exercício Físico/psicologia , Motivação , Caracteres Sexuais , Inquéritos e Questionários , Adolescente , Feminino , Humanos , Masculino , PolôniaRESUMO
In this study, a direct sulfidation reaction of ammonium perrhenate (NH4ReO4) leading to a synthesis of rhenium disulfide (ReS2) is demonstrated. These findings reveal the first example of a simplistic bottom-up approach to the chemical synthesis of crystalline ReS2. The reaction presented here takes place at room temperature, in an ambient and solvent-free environment and without the necessity of a catalyst. The atomic composition and structure of the as-synthesized product were characterized using several analysis techniques including energy dispersive x-ray spectroscopy, x-ray photoelectron spectroscopy, x-ray diffraction, transmission electron microscopy, Raman spectroscopy, thermogravimetric analysis and differential scanning calorimetry. The results indicated the formation of a lower symmetry (1T') ReS2 with a low degree of layer stacking.
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We show a novel chemical vapour deposition (CVD) approach, in which the large-scale fabrication of ferromagnetically-filled cm-scale buckypapers is achieved through the deposition of a mesoporous supported catalyst (SBA-16) on a silicon substrate. We demonstrate that SBA-16 has the crucial role of promoting the growth of carbon nanotubes (CNTs) on a horizontal plane with random orientation rather than in a vertical direction, therefore allowing a facile fabrication of cm-scale CNTs buckypapers free from the onion-crust by-product observed on the buckypaper-surface in previous reports. The morphology and composition of the obtained CNTs-buckypapers are analyzed in detail by scanning electron microscopy (SEM), Energy Dispersive X-ray (EDX), transmission electron microscopy (TEM), high resolution TEM (HRTEM), and thermogravimetric analysis (TGA), while structural analysis is performed by Rietveld Refinement of XRD data. The room temperature magnetic properties of the produced buckypapers are also investigated and reveal the presence of a high coercivity of 650 Oe. Additionally, the electrochemical performances of these buckypapers are demonstrated and reveal a behavior that is compatible with that of a pseudo-capacitor (resistive-capacitor) with better performances than those presented in other previously studied layered-buckypapers of Fe-filled CNTs, obtained by pyrolysis of dichlorobenzene-ferrocene mixtures. These measurements indicate that these materials show promise for applications in energy storage systems as flexible electrodes.