Search

Carbonaceous materials have gained significant attention in recent years for their various applications in the field of medicine and biotechnology. This comprehensive review explores the synthesis and characterization of carbon-based materials and their potentials in various medical applications. The paper delves into the methods of fabrication of carbon-based nanoparticles, such as carbon nanotubes, biochar, and graphene, while highlighting their unique properties. Characterization techniques, such as microscopy, spectroscopy, and surface analysis, are discussed to provide insights into the chemical and structural properties of these materials. Furthermore, the review examined their wide-ranging medical applications, encompassing tissue engineering, drug delivery, biosensing, and imaging, showcasing the versatility and promising contributions of carbonaceous materials in the healthcare industry. The review outlines the current challenges and prospects in the field, emphasizing the growing significance of carbon-based materials as valuable tools in advancing medical science and technology, as well as public health. [ABSTRACT FROM AUTHOR]

ABSTRACT Raman spectroscopy of carbonaceous materials (RSCM) was applied to 10 carbonaceous material (CM) ‐rich low‐ to medium‐grade metasedimentary rock samples of Western Himalaya, Pakistan to assess their optimum thermal evolution. The RSCM thermometry is based on the degree of graphitisation of CM as a function of peak metamorphic temperature. Petrographic observations of the studied samples revealed two dominant CM morphologies. Type‐I CM, represented by fine‐grained discontinuous dust‐like and scattered to thin sporadic layers, was more prevalent in low‐grade metamorphic samples. Type‐II CM, corresponding to continuous and extended thick fibres and elongated grain constellations, was dominant in medium‐ to high‐grade metamorphic samples. The degree of crystallinity of CM and subsequent metamorphic temperatures were quantified by considering the intensity‐based R1 and the area‐based R2 ratio parameters. Low‐grade samples from the Lesser Himalayan Sequence (LHS), having Type‐I CM, resulted in RSCM peak temperatures between 306°C and 403°C. Medium‐ to high‐grade samples from Higher Himalayan Crystalline (HHC), containing Type‐II CM, yielded peak temperatures in the 482°C–560°C range. The extremely deformed sample from a fault zone in the LHS produced relatively higher temperature of 403°C, thereby suggesting heat associated with shearing due to fault activities resulting in CM recrystallisation and elevated temperature values. The study revealed that the peak metamorphic temperatures increase from south towards north following a progressive path of metamorphism in the region. [ABSTRACT FROM AUTHOR]

This study examined the adsorption capacities of biochars derived from kenaf (KF‐BCs) for the removal of heavy metals such as Cu(II) and Pb(II). The thermal decomposition temperature (300–750°C) significantly influenced the morphology and composition of KF‐BCs, enhancing their surface area, pore structure, and alkalinity. Among them, kenaf pyrolyzed at 750°C (KF‐750) was the most effective in removing Cu(II) and Pb(II), as validated by kinetic, equilibrium, and isotherm model analyses. Adsorption kinetics revealed that equilibrium was attained after 24 h, with chemisorption governing the process rate. Equilibrium adsorption conformed to the Langmuir and Freundlich models for Cu(II) and Pb(II), respectively. KF‐750 exhibited midrange adsorption capacities for Cu(II) and Pb(II) (23.47 ± 0.3 mg/g and 50.07 ± 0.9 mg/g, respectively), compared with the literature. The thermodynamic assessment revealed an endothermic process with positive ∆H0, indicating that higher temperatures favor metal adsorption. At low pH, adsorption decreased due to electrostatic repulsion, particularly affecting Cu(II). More than 99.8% of Cu(II) and Pb(II) were removed with a 5.00 g/L KF‐750 dose. The cation effect order on KF‐750 was Ca2+ > Mg2+ > Na+ > K+. Overall, KF‐750 demonstrates promising potential as an adsorbent for the efficient heavy metal removal from aqueous solutions, presenting a viable option for environmental remediation. [ABSTRACT FROM AUTHOR]

The Huangjindong gold deposit in northeastern Hunan is one of the most representative gold deposits in the Jiangnan Orogenic Belt. The orebodies are mainly hosted in the Neoproterozoic Lengjiaxi Group, which comprises carbonaceous slates. Abundant carbonaceous material (CM) can be found in the host rocks and ore-bearing quartz veins, but its geological characteristics and genesis, as well as its association with gold mineralization, are still unclear. Systematic petrographic observation demonstrated two types of CM in host rocks and ores, i.e., CM1 and CM2. Among them, CM1 is the predominant type and mainly occurs in the layered carbonaceous slates, while CM2 is mostly present in quartz veins and mineralized host rocks. Laser Raman spectroscopic analyses of CM1 were performed at higher temperatures (376–504 °C), and CM2 was generated at similar temperatures (255–435 °C) to gold mineralization. Combined with previous studies, we can conclude that CM1 was produced by Neoproterozoic to early Paleozoic metamorphism before gold mineralization, while CM2 is of hydrothermal origin. Geochemical modeling indicates that CM1 could promote gold precipitation through reduction, as well as facilitate structure deformation and metal absorption as previously proposed. However, hydrothermal CM2 is favorable for gold mineralization because it triggers sulfidation, similar to other Fe-bearing minerals (such as siderite) in the host rocks. Consequently, both types of CM in the Huangjindong deposit are favorable for gold mineralization and carbonaceous slates could be important gold-bearing units for future ore prospecting in the Jiangnan Orogen as well as other places in South China. [ABSTRACT FROM AUTHOR]

Benzene is a toxic substance among the volatile organic compounds threatening public health even at low concentrations. Of the many volatiles, it is used in several solvent-based productions and can quickly turn into a gas phase at room temperature. The importance of benzene exposure may be a risk to humans if the amount increases indoors due to an identified carcinogen. However, traditional adsorbents play a lowly role in the purification and separation of benzene. In this paper, the performance of produced adsorbents (GR1-150AC) on benzene removal efficiencies from Gleditsia riacanthos L. has been evaluated by chemical activation treatment. Among the tested adsorbents, GR54AC and GR118AC are better than most adsorbents for removing benzene. Here, GR54AC and GR118AC were produced with 1:3 (w/v) H2SO4 and 1:4 (w/v) HCl activation at a setting carbonization temperature of 700 and 800 °C, respectively. The pore volumes also reflected the success of HCl and H2SO4 activation, which attained GR54AC (894 m2/g) and GR118AC (748 m2/g); the total pore volume was 0.43 and 0.24 cm3/g, while the micropore volume was 0.32 and 0.16 cm3/g. Moreover, the excellent amount adsorbed with GR54AC varies from 123 to 273 mg/g, and the amount adsorbed of GR118AC increased from 82 to 235 mg/g for 180-min retention time. Results are exciting to assist recent paths for optimizing air filtration systems under actual environmental conditions, particularly regarding its compatibility with the benzene molecular structure of GR54AC. [ABSTRACT FROM AUTHOR]

Parabens are a family of p-hydroxybenzoic acid esters used as preservatives in food, cosmetics, and pharmaceuticals products, parabens are pollutants that have been detected in the environment at low concentrations. Recent research describes that parabens can cause health alterations. Alternatives for contaminant removal include the adsorption process, which can use materials that are abundant, inexpensive and susceptible to modifications. In this sense, biochar can be an option for obtaining materials that can be used for pollutants removal.In this report, we present the use of biochar derived from fique bagasse as an adsorbent for the removal of butylparaben (BP) from water. This paper examines how pH variations influence the adsorption capacity of butylparaben onto fique bagasse biochar, it was determined that the highest adsorption capacity occurred at pH 6. Furthermore, pseudo-first order, pseudo-second order, Weber and Morris, and Boyd models were used to study the adsorption kinetics. As a result, the pseudo-first order model was favorable for six carbonaceous materials studied. Finally, Freundlich, Langmuir, and Sips adsorption isotherm models were investigated; the Langmuir model was the best for adsorption isotherm data. The maximum adsorption capacity of BP for FB-3Na was 20.9520 mg g−1.

Abstract Carbonaceous material (CM) undergoes progressive changes that reflect its thermal history. These changes are in general irreversible and provide valuable information for understanding diagenetic and metamorphic processes of crustal rocks. Among various approaches to quantify these changes, the R2 ratio, area ratio of specific peaks in CM Raman spectra, is widely used to estimate the maximum temperature of intermediate- to moderately high-grade metamorphism. The calculation of the R2 ratio requires peak deconvolution of the original spectrum, and the results depend on the details of how this is carried out. However, a clear protocol for selecting appropriate initial conditions has not been established and obtaining a reliable temperature estimate depends at least in part on the experience and skill of the operator. In this study, we developed a Python code that automatically calculates the R2 ratio from CM Raman spectra. Our code produces R2 ratios that are generally in good agreement with those of Aoya et al. (J Metamorph Geol 28:895–914, 2010, https://doi.org/10.1111/j.1525-1314.2010.00896.x ) for the same Raman data, with much less time and effort than was the case in the previous studies. We have confirmed that the code is also applicable to other previous datasets from both contact and regional metamorphic regions. The overall trend of the recalculated data indicates that samples with R2 greater than ~ 0.7 are not sensitive to the changes in CM maturity and thus should not be used for the calibration of an R2-based geothermometer. We propose a modified geothermometer for contact metamorphism that is strictly applicable to samples with R2 from 0.023 to 0.516, with the proviso that a laser with a wavelength of 532 nm should be used. A slight extrapolation of the newly proposed geothermometer up to R2 of 0.57 provides a temperature estimate that is consistent with the geothermometer of Kaneki and Kouketsu (Island Arc 31:e12467, 2022; https://doi.org/10.1111/iar.12467 ); the boundary between the two geothermometers corresponds to a temperature of 391 °C.

Unsustainable pig breeding is a great threat to the environment. Ammonia is one of the main pollutants emitted in piggery vent air. This work is a comparative survey that presents the findings on the effectiveness of ammonia adsorption from air using various activated carbons (ACs). Detailed consideration is given to the effects of (i) type of raw material (wood char, wood pellet, and commercial lignite-based char), (ii) preparation method (CO2, steam, and KOH activation), and (iii) activation conditions (temperature and KOH/char ratio), on the porous structure of ACs and their ammonia sorption capacity and reversibility. Response surface methodology and genetic algorithm were used to find optimum KOH activation conditions. Economic analyses of AC production were performed using process modeling in Aspen software. It was found that ACs obtained from wood char in KOH activation show a maximum ammonia capacity of 397 g/kg, which is at least 2.5-fold higher than that reached on ACs from physical activation. A lower activation temperature (<750 °C) and a higher KOH/char ratio (>3) were preferred for effective adsorption, regardless of the type of feedstock. High sorption reversibility was achieved (87–96%). This makes the obtained sorbents promising sorbents for ammonia removal from piggery vent air with potential subsequent application as nitrogen-enriched biochar for crop fertilization. Thus, it facilitates sustainable pig breeding. [ABSTRACT FROM AUTHOR]

Carbonaceous materials hydrothermally produced using waste biomass have small specific surface areas (SSA) and poor porosity properties. In this study, we prepare a novel carbonaceous material with excellent porosity properties by suppressing the formation of a secondary char phase (spheres) and promoting biomass hydrolysis by controlling the hydrothermal conditions. Rice husk powders, as the starting material, are hydrothermally treated using acidic solvents of different types and concentrations at 180 °C. The surfaces of the samples hydrothermally prepared using the acidic solvents have no spheres. In the case of 0.1–0.2 mol L−1 hydrochloric acid (HA), the amorphous carbonaceous materials contain numerous mesopores and exhibit a larger SSA (approximately 100 m2 g−1) than those prepared using acetic acid and distilled water. An increase in the hydrothermal temperature reduces the porosity properties of the materials. Finally, the high-porosity amorphous carbonaceous material showed excellent trimethylamine adsorption ability. [ABSTRACT FROM AUTHOR]

Carbonaceous material (CM) undergoes progressive changes that reflect its thermal history. These changes are in general irreversible and provide valuable information for understanding diagenetic and metamorphic processes of crustal rocks. Among various approaches to quantify these changes, the R2 ratio, area ratio of specific peaks in CM Raman spectra, is widely used to estimate the maximum temperature of intermediate- to moderately high-grade metamorphism. The calculation of the R2 ratio requires peak deconvolution of the original spectrum, and the results depend on the details of how this is carried out. However, a clear protocol for selecting appropriate initial conditions has not been established and obtaining a reliable temperature estimate depends at least in part on the experience and skill of the operator. In this study, we developed a Python code that automatically calculates the R2 ratio from CM Raman spectra. Our code produces R2 ratios that are generally in good agreement with those of Aoya et al. (J Metamorph Geol 28:895–914, 2010, https://doi.org/10.1111/j.1525-1314.2010.00896.x) for the same Raman data, with much less time and effort than was the case in the previous studies. We have confirmed that the code is also applicable to other previous datasets from both contact and regional metamorphic regions. The overall trend of the recalculated data indicates that samples with R2 greater than ~ 0.7 are not sensitive to the changes in CM maturity and thus should not be used for the calibration of an R2-based geothermometer. We propose a modified geothermometer for contact metamorphism that is strictly applicable to samples with R2 from 0.023 to 0.516, with the proviso that a laser with a wavelength of 532 nm should be used. A slight extrapolation of the newly proposed geothermometer up to R2 of 0.57 provides a temperature estimate that is consistent with the geothermometer of Kaneki and Kouketsu (Island Arc 31:e12467, 2022; https://doi.org/10.1111/iar.12467); the boundary between the two geothermometers corresponds to a temperature of 391 °C. [ABSTRACT FROM AUTHOR]

Mobile herbicides have a high potential for groundwater contamination. An alternative to decrease the mobility of herbicides is to apply materials with high sorbent capacity to the soil, such as biochars. The objective of this research was to evaluate the effect of eucalyptus, rice hull, and native bamboo biochar amendments on sorption and desorption of hexazinone, metribuzin, and quinclorac in a tropical soil. The sorption–desorption was evaluated using the batch equilibrium method at five concentrations of hexazinone, metribuzin, and quinclorac. Soil was amended with eucalyptus, rice hull, and native bamboo biochar at a rate of 0 (control—unamended) and 1% (w w−1), corresponding to 0 and 12 t ha−1, respectively. The amount of sorbed herbicides in the unamended soil followed the decreasing order: quinclorac (65.9%) > metribuzin (21.4%) > hexazinone (16.0%). Native bamboo biochar provided the highest sorption compared to rice hull and eucalyptus biochar–amended soils for the three herbicides. The amount of desorbed herbicides in the unamended soil followed the decreasing order: metribuzin (18.35%) > hexazinone (15.9%) > quinclorac (15.1%). Addition of native bamboo biochar provided the lowest desorption among the biochar amendments for the three herbicides. In conclusion, the biochars differently affect the sorption and desorption of hexazinone, metribuzin, and quinclorac mobile herbicides in a tropical soil. The addition of eucalyptus, rice hull, and native bamboo biochars is a good alternative to increase the sorption of hexazinone, metribuzin, and quinclorac, thus, reducing mobility and availability of these herbicides to nontarget organisms in soil. [ABSTRACT FROM AUTHOR]

The purpose of this work is to study the influence of the activation temperature on the porous structure characteristics of carbonaceous materials (CMs) prepared from long-flame coal under thermoprogrammed activation at the KОН/coal ratio RKOH = 1.0 g/g. The CMs were obtained in argon in three stages: 1) heating (4 grad/min) to the specified temperature t in the range of 350–825 °С; 2) isothermal exposure 1 h; 3) cooling, washing from alkali and drying. Samples are denoted as CM(t). The CM yield (Y, %) and CMs elemental composition are determined. Based on low-temperature (77 K) nitrogen adsorption-desorption isotherms, integral and differential dependences of the specific surface area SDFT (m² /g) and pore volume V (cm³ /g) on the average pore diameter (D, nm) were calculated by 2D-NLDFT-НS method (SAIEUS program). They were used to define volumes of ultramicropores (Vumi), supermicropores (Vsmi) and micropores (Vmi). The total pore volume V was calculated from the nitrogen amount adsorbed at a relative pressure p/p0 ~ 1.0. The S values of ultramicropores (Sumi), supermicropores (Ssmi) and micropores (Smi) were similarly determined. The CM yield was established to decrease linearly (R² = 0.979) from 70.2 to 45.3 % with an increase in temperature from 350 to 825 °С. The carbon content decreases to a minimum value at 500 °С (72.6 %), and then increases to a maximum value (87.5 %) at 825 °С; the oxygen content changes antibatically. Two temperature regions were identified: region I (≤ 500 °С) of increasing the oxygen content due to reactions in which KOH acts as a donor of O atoms; region II (≥ 500 °C) of dominating the thermal destruction of functional groups (carboxyl, lactone, ester) with the release of CO and CO2, and condensation increasing the size of polyarenes of the CM secondary framework and formsng single Сar-Саr bonds between them. The CM(350) sample was found to contain only mesopores (D ≥ 10 nm) and macropores. An activation temperature increase to 400 °C initiates the additional formation of small-diameter micropores and mesopores. In samples CM(400) - CM(825), the main portion of newly formed pores falls on pores with D ≤ 5 nm. With increasing temperature, the micropores volume increases almost linearly (R² = 0.992). The Vumi and Vsmi volumes increase up to 600 °C. At higher temperatures the ultramicropores volume decreases due to transforming ultramicropores (D ≤ 0.7 nm) into supermicropores (D = 0.7–2.0 nm). Portion of the ultramicropores volume changes with a maximum (23.9 %) in the CM(600) sample. The SBET specific surface area linearly (R² = 0.992) increases with temperature up to 1729 m² /g. The SDFT values are close to SBET, but noticeably lower (1514–1530 m² /g) for CM(785)-CM(825). The micropores specific surface area increases to 1415 m² /g, and ultramicropore surface Sumi changes extremely with a maximum (526 m² /g) for the CM(600) sample, which should be expected based on the temperature dependence of the Vumi parameter. The decrease in Sumi values after the maximum is compensated by an increase in the supermicropore surface. Such an effect - the redistribution of pores by size in the microporous range (D ≤ 2 nm) with an increase in the alkaline activation temperature is not described in the literature. The portion of the micropores surface is dominant (92.6–97.0 %) in samples prepared at t ≥ 450 °C. The portion of the ultramicropore surface is maximum (56.3 %) in CM(500). Pores are revealed that do not form at all at 450–750 °C. These are supermicropores (D = 0.96–2.00 nm) and mesopores of small diameters (D = 2.0–2.82 nm). This effect was assumed to be due to the properties of the CM supramolecular framework, which is formed from polyarene fragments of the initial and activated coals having polyarenes with diameters of the same order (1.68–2.54 nm). [ABSTRACT FROM AUTHOR]

Asbestos is a term that includes six fibrous mineral phases related to different lung diseases, including asbestosis, lung cancer, and Malignant Pleural Mesothelioma (MPM). Since the last century, these minerals have been widely studied under their mineralogical/chemical and physical aspects with in vivo and in vitro studies to understand the mechanisms of their carcinogenicity. There are several techniques described in the literature, as optical and electron microscopies, for the identification of coated (asbestos bodies, ABs) and uncoated fibers, but only micro-Raman spectroscopy permits a sure characterization of these minerals—and of the related phases—directly in the histological sections of pulmonary parenchyma without any manipulation. In this case, the risk of the loss of associated inorganic phases from asbestos bodies (ABs) and fibers (e.g.: iron or carbonaceous micro-particles) is avoided. Asbestos bodies are produced by the activity of alveolar macrophages with degradation/inactivation of asbestos fibers. Inside the alveolar macrophages, organic and inorganic material settles on the foreign fibers forming an iron-rich proteic and carbonaceous coating. In this study, Variable Pressure Scanning Electron Microscopy with annexed Electron Dispersive Spectroscopy (VP-SEM/EDS) and micro-Raman spectroscopy were applied to the characterization of the phases in the ABs. Characterization of carbonaceous materials (CMs), observed in pristine asbestos phases in previous works, was therefore performed, addressing the micro-Raman laser beam on different points of the asbestos bodies, and Raman mappings on ABs were carried out for the first time. Coupling the data obtained by VP-SEM/EDS and micro-Raman spectroscopy, it was possible to collect information about the iron and carbonaceous phases adhered to the fibers, probably lost during the classical tissue digestion procedures. Information about both mineral and carbonaceous components might be useful to understand the whole structure of "asbestos bodies" and the inflammogenic and carcinogenic effects of the asbestos phases coupled to CMs, that might derive from cigarette smoke or from environmental pollution; this study might be useful to deepen also the possible detrimental role of ABs in the tissues. [ABSTRACT FROM AUTHOR]

New geothermometry using laser‐Raman data on carbonaceous material from low and intermediate grade rocks on Santa Catalina Island, California, together with existing thermobarometric data, show that there is a quasi‐continuous increase in peak metamorphic temperature from 327 ± 8°C in lawsonite blueschist facies rocks at the lowest structural levels, through ∼433°C in overlying epidote blueschists, 546 ± 20°C in albite‐epidote amphibolite facies rocks, to 650–730°C in amphibolite facies rocks at the top of the sequence. Rocks of different metamorphic grade are separated from one another by tectonic contacts across which temperature increases by ∼100°C in each case. Previously published geochronological data indicate that peak metamorphism in the highest grade rocks at 115 Ma preceded deposition of blueschist facies metasediments by ∼15 million years, so that the present inverted grade sequence does not represent an original inverted temperature gradient. The present structure results from progressive underplating of oceanic rocks in a cooling subduction zone following a high‐T metamorphic event at 115 Ma. An inverted temperature gradient of ≥100°C/km across the subduction channel likely existed during the high‐T event, decreased during underplating, and reached zero by ∼90 Ma. Key Points: New geothermometry shows that high‐pressure rocks on Catalina define an inverted metamorphic temperature zonationThe zonation is disrupted, and the present structure does not represent an original inverted thermal gradientThe zonation formed by progressive underplating in a cooling subduction zone following a high‐T metamorphic event [ABSTRACT FROM AUTHOR]

Industrial recovery of valuable elements in copper slag is the key to treat copper slag and protect the environment. However, the results of the industrial reduction of copper slag are not ideal at present, mainly because the oxidation problem caused by excess oxygen is not considered. In this study, the properties of three carbonaceous materials and the coupling reaction behavior of copper slag + C under CO2 atmosphere were investigated by thermogravimetric and thermokinetic analyses. The results showed the activity of the three carbonaceous materials to be in the order of coke > anthracite > coal. Coke was more conducive to the reduction of copper slag under Ar atmosphere, whereas anthracite was more conducive under CO2 atmosphere. The reduction amount and rate of copper slag under CO2 atmosphere were higher than those under Ar atmosphere within a certain temperature range. Moreover, the carbon burning loss increased significantly so that CO2 could re-oxidize the reduced metal elements after heating to 1300 ℃. The limiting steps of the reduction reaction of copper slag under Ar atmosphere mainly followed the three-dimensional diffusion (ZLT) model. On the other hand, under CO2 atmosphere, the limiting steps of some of the reactions changed due to the influence of the coupling reaction. Overall, we observed that the activation energies of the reduction and oxidation reactions under coupling conditions were higher.

Biochar is a carbonaceous material, which can be decorated with metals, that has been garnering attention to be used in the treatment of water due to its contribution to waste management and circular economy. This study presents the life cycle assessment (LCA) regarding the generation of Pinus patula raw biochar and its modification with iron (Fe-modified biochar). SimaPro 9.3.0.3 software was used to simulate the environmental impacts of both carbonaceous materials. The potential environmental effects obtained from the production of Pinus patula raw biochar were mainly ascribed to the source of energy utilized during this process. The potential impacts demonstrated that the generation of gases and polycyclic aromatic hydrocarbons are the main concern. In the case of Fe-modified biochar, the potential environmental effects differed only in the stage of the biomass modification with the metal. These effects are associated with the extraction of Fe and the generation of wastewater. These findings provide an insight into the environmental effects linked to the production of raw and Fe-modified biochar. However, further LCA research should be performed concerning other materials and compounds than can be generated during the biomass thermochemical conversion. [ABSTRACT FROM AUTHOR]

Biochar-amended soils influence the degradation of herbicides depending on the pyrolysis temperature, application rate, and feedstock used. The objective of this study was to evaluate the influence of sugarcane straw biochar (BC) produced at different pyrolysis temperatures (350 °C, 550 °C, and 750 °C) and application rates in soil (0, 0.1, 0.5, 1, 1.5, 5, and 10% w/w) on metribuzin degradation and soil microbiota. Detection analysis of metribuzin in the soil to find time for 50% and 90% metribuzin degradation (DT50 and DT90) was performed using high-performance liquid chromatography (HPLC). Soil microbiota was analyzed by respiration rate (C-CO2), microbial biomass carbon (MBC), and metabolic quotient (qCO2). BC350 °C-amended soil at 10% increased the DT50 of metribuzin from 7.35 days to 17.32 days compared to the unamended soil. Lower application rates (0.1% to 1.5%) of BC550 °C and BC750 °C decreased the DT50 of metribuzin to ~4.05 and ~5.41 days, respectively. BC350 °C-amended soil at high application rates (5% and 10%) provided high C-CO2, low MBC fixation, and high qCO2. The addition of low application rates (0.1% to 1.5%) of sugarcane straw biochar produced at high temperatures (BC550 °C and BC750 °C) resulted in increased metribuzin degradation and may influence the residual effect of the herbicide and weed control efficiency. [ABSTRACT FROM AUTHOR]

Carbonaceous materials are a highly appealing class of adsorbents, owing to their exceptional properties, such as high surface area and thermal and chemical stability. These materials have found successful applications in water purification. Sweet chestnut (Castanea sativa) cupules are disposed of as waste. Valorization of these residues is a step forward in terms of circular economy and sustainability. Meanwhile, per- and poly-fluoroalkyl substances (PFASs) pose significant concerns due to their persistence, bioaccumulation, and toxicity, emerging as contaminants of concern for human health and the environment. This study focuses on preparing carbonaceous material by hydrothermal carbonization from chestnut cupules, followed by their use as adsorbents for PFAS removal from polluted water. The cupule waste material was crushed, ground, sieved, and subjected to hydrothermal treatment at temperatures ranging from 180–200 °C to produce hydrothermal carbons. The adsorbents obtained were characterized by various techniques such as nitrogen adsorption isotherm, porosimetry, point of zero charge, Fourier-transform infrared, scanning electron microscopy, and thermal, elemental, and energy dispersive X-ray analyses. Surface area (SBET) values of 42.3–53.2 m2·g−1 were obtained; pHPZC ranged from 3.8 to 4.8. This study also determined the adsorption kinetics and isotherms for removing perfluorooctanoate-contaminated water. The equilibrium was established at 72 h and qe = 1029.47 mg·g−1. To summarize, this research successfully valorized a biomass residue by transforming it into hydrothermal carbon, which was then utilized as an adsorbent for water decontamination. [ABSTRACT FROM AUTHOR]

Asbestos is a term that includes six fibrous mineral phases related to different lung diseases, including asbestosis, lung cancer, and Malignant Pleural Mesothelioma (MPM). Since the last century, these minerals have been widely studied under their mineralogical/chemical and physical aspects with in vivo and in vitro studies to understand the mechanisms of their carcinogenicity. There are several techniques described in the literature, as optical and electron microscopies, for the identification of coated (asbestos bodies, ABs) and uncoated fibers, but only micro-Raman spectroscopy permits a sure characterization of these minerals—and of the related phases—directly in the histological sections of pulmonary parenchyma without any manipulation. In this case, the risk of the loss of associated inorganic phases from asbestos bodies (ABs) and fibers (e.g.: iron or carbonaceous micro-particles) is avoided. Asbestos bodies are produced by the activity of alveolar macrophages with degradation/inactivation of asbestos fibers. Inside the alveolar macrophages, organic and inorganic material settles on the foreign fibers forming an iron-rich proteic and carbonaceous coating. In this study, Variable Pressure Scanning Electron Microscopy with annexed Electron Dispersive Spectroscopy (VP-SEM/EDS) and micro-Raman spectroscopy were applied to the characterization of the phases in the ABs. Characterization of carbonaceous materials (CMs), observed in pristine asbestos phases in previous works, was therefore performed, addressing the micro-Raman laser beam on different points of the asbestos bodies, and Raman mappings on ABs were carried out for the first time. Coupling the data obtained by VP-SEM/EDS and micro-Raman spectroscopy, it was possible to collect information about the iron and carbonaceous phases adhered to the fibers, probably lost during the classical tissue digestion procedures. Information about both mineral and carbonaceous components might be useful to understand the whole structure of “asbestos bodies” and the inflammogenic and carcinogenic effects of the asbestos phases coupled to CMs, that might derive from cigarette smoke or from environmental pollution; this study might be useful to deepen also the possible detrimental role of ABs in the tissues.

Phenolic compounds (PhCs) are ubiquitously distributed phytochemicals found in many plants, body fluids, food items, medicines, pesticides, dyes, etc. Many PhCs are priority pollutants that are highly toxic, teratogenic, and carcinogenic. Some of these are present in body fluids and affect metabolism, while others possess numerous bioactive properties such as retaining antioxidant and antimicrobial activity in plants and food products. Therefore, there is an urgency for developing an effective, rapid, sensitive, and reliable tool for the analysis of these PhCs to address their environmental and health concern. In this context, carbonaceous nanomaterials have emerged as a promising material for the fabrication of electrochemical biosensors as they provide remarkable characteristics such as lightweight, high surface: volume, excellent conductivity, extraordinary tensile strength, and biocompatibility. This review outlines the current status of the applications of carbonaceous nanomaterials (CNTs, graphene, etc.) based enzymatic electrochemical biosensors for the detection of PhCs. Efforts have also been made to discuss the mechanism of action of the laccase enzyme for the detection of PhCs. The limitations, advanced emerging carbon-based material, current state of artificial intelligence in PhCs detection, and future scopes have also been summarized. [ABSTRACT FROM AUTHOR]

Bonechar presents high sorption capacity for mobile herbicides retained in soil and water. However, its use in a granulated and/or powder form makes it difficult to remove water. The objective of this study was to produce a cellulose acetate film with bonechar as a viable alternative to remove metribuzin from water. The treatments were composed of 2 and 3 g of bonechar fixed on a cellulose acetate film, pure bonechar, and a control (no bonechar). The sorption and desorption study was carried out in the equilibrium batch mode with five concentrations of metribuzin (0.25, 0.33, 0.5, 1, and 2 mg L−1). The water used in the experiment was potable water. Herbicide analysis was performed by High-Performance Liquid Chromatography (HPLC). The addition of 2 and 3 g of the bonechar fixed on the acetate film sorbed 40% and 60%, respectively, of the metribuzin at the lowest concentrations (0.25, 0.33, and 0.5 mg L−1). For both additions, desorption was low, being 7% and 2.5% at 24 and 120 h, respectively. There are still no reports of the production of cellulose acetate film with bonechar for herbicide removal in water, considered an alternative of easy handling and indicated for water treatment plants. [ABSTRACT FROM AUTHOR]

The carbonaceous material (CM) prepared by refinery oily sludge was proposed to remove flotation collectors, butyl xanthate (BX), and diethyldithiocarbamate (DDTC) in synthetic wastewater. The effects of the CM on removal efficiency, adsorption kinetics, and isotherms were experimentally carried out. The surface structure and composition of CM were characterized by BET isotherm, XRD, and SEM-EDS, and the concentration of BX and DDTC was tested by UV-VIS spectrometer. The adsorption behavior and removal mechanism were investigated by zeta potential, ToF-SIMS, FTIR, etc. The removal efficiencies of BX and DDTC were both more than 99%, and the maximum adsorption capacity peaked when the pH of the solution was neutral. The two collectors were heterogeneous adsorption on the surface of CM. BX, DDTC, and related metal compounds were found on the surface of carbonaceous material, confirming the existence of both physical and chemical adsorption, and physical adsorption accounted for the main mechanism. It is proved that BX and DDTC can be removed by carbonaceous material and realize the high-effective utilization of refinery oily sludge. [ABSTRACT FROM AUTHOR]

Parabens are a family of p-hydroxybenzoic acid esters used as preservatives in food, cosmetics, and pharmaceuticals products, parabens are pollutants that have been detected in the environment at low concentrations. Recent research describes that parabens can cause health alterations. Alternatives for contaminant removal include the adsorption process, which can use materials that are abundant, inexpensive and susceptible to modifications. In this sense, biochar can be an option for obtaining materials that can be used for pollutants removal. In this report, we present the use of biochar derived from fique bagasse as an adsorbent for the removal of butylparaben (BP) from water. This paper examines how pH variations influence the adsorption capacity of butylparaben onto fique bagasse biochar, it was determined that the highest adsorption capacity occurred at pH 6. Furthermore, pseudo-first order, pseudo-second order, Weber and Morris, and Boyd models were used to study the adsorption kinetics. As a result, the pseudo-first order model was favorable for six carbonaceous materials studied. Finally, Freundlich, Langmuir, and Sips adsorption isotherm models were investigated; the Langmuir model was the best for adsorption isotherm data. The maximum adsorption capacity of BP for FB-3Na was 20.9520 mg g -1 ., (© 2024 The Author(s).)

Summary: Hydrogen being abundant, eco‐friendly, is a promising alternative energy source to fossil fuels. Its practical application is limited because of difficulty in storage due to low energy density and safety issues. Solid‐state electrochemical hydrogen storage is a promising method among several approaches of hydrogen storage to meet the U.S. Department of Energy's (DOE) targets. Till 2020, no hydrogen storage material has achieved targets due to lack of proper strategies. In view of meeting targets decided by U.S. DOE, a detailed review of whole progress made in electrochemical hydrogen storage approaches and materials is presented. The reported hydrogen storage capacities of Graphene (1.21 wt.%), reduced Graphene Oxide (2.7 wt.%), Mg‐based alloys (up to 7.6 wt.%), hydrogen clathrates (up to 4.2 wt.%), Pervoskite oxides (up to 4 wt.%), and Nd2Sn2O7 (up to 14.86 wt.%) are consolidated at one place and disclosed. The shortcomings hindering current hydrogen storage technologies are summarized and the scope of future improvement in hydrogen storage is outlined. Emerging materials and technologies are mentioned which can progress towards achieving U.S. DOE targets. This review can assist researchers in choosing an appropriate strategy or potential material for electrochemical hydrogen storage. Highlights: Achievements in electrochemical hydrogen storage are reviewed.Improvement techniques in conventional electrochemical hydrogen storage are presented in tabular form.Emergences in hydrogen storage materials are listed.Future perspective to meet US DOE targets is decided on basis of review. [ABSTRACT FROM AUTHOR]

Pyrolysis temperature and application rate of biochar to soil can influence herbicide behavior and soil fertility. The objective was to investigate the effect of soil amendments with application rates of sugarcane straw biochar, produced at different pyrolysis temperatures, on the sorption–desorption of metribuzin in soil. The analysis was performed using high-performance liquid chromatography (HPLC). The treatments were three pyrolysis temperatures (BC350, BC550 and BC750 °C) and seven application rates (0, 0.1, 0.5, 1, 1.5, 5 and 10% w w−1). Amended soil with different application rates decreased H + Al and increased pH, OC, P, K, Ca, Mg, Fe, Mn, CEC and BS contents. Kf values of sorption and desorption of metribuzin were 1.42 and 0.78 mg(1−1/n) L1/n Kg−1, respectively, in the unamended soil. Application rates < 1% of biochar sorbed ~23% and desorbed ~15% of metribuzin, similar to unamended soil, for all pyrolysis temperatures. Amended soil with 10% of BC350, BC550 and BC750 sorbed 63.8, 75.5 and 89.4% and desorbed 8.3, 5.8 and 3.7% of metribuzin, respectively. High pyrolysis temperature and application rates of sugarcane straw biochar show an ability to immobilize metribuzin and improve soil fertility, which may influence the effectiveness in weed control. [ABSTRACT FROM AUTHOR]

We developed a flexible electrode based on a bismuth molybdate/graphene (BiM/GR) nanocomposite for electrochemical detection of mercury (Hg2+). The formation of the BiM/GR nanocomposite was systematically examined with suitable characterization studies. The BiM/GR-modified electrodes exhibit a high electrocatalytic performance toward Hg2+ detection comparable to other electrodes. The excellent electrocatalytic activity of the BiM/GR nanocomposite can be attributed to its good conductivity, synergistic effect, and abundant active site. Notably, the BiM/GR sensor showed good electrochemical sensing performance for Hg2+ in the wide detection range from 0.02 to 149 μM with a good sensitivity of 9.5 μA μM–1 cm2 and an ultralow detection limit of 5.0 nM, which is well below the threshold value set by the World Health Organization (30 nM) and the United States Environmental Protection Agency. More importantly, the BiM/GR nanocomposite-modified electrode was used successfully to detect Hg2+ in river water, corn, and fish samples with satisfactory recovery values. [ABSTRACT FROM AUTHOR]

Exposure to BTEX concentrations may have a remarkable influence on human health because of their existence in indoor air. It is the only solution to remove BTEX from the environment by either ventilation or filtering. Activated carbon is the primary carbon-rich material for the BTEX pollution control strategy. In this study, Digitalis purpurea L. biomass as lignocellulosic materials was selected as a common substance in nature and carbonization-appropriate processing. The activated carbons (DPAC1-60) were prepared from the pyrolysis of Digitalis purpurea L. biomass at 500–900 °C by chemical activation with Zinc chloride (ZnCl2), Potassium carbonate (K2CO3), Sulfuric acid (H2SO4), and Phosphoric acid (H3PO4), respectively. The DPACs structure enrichment was targeted with several conditions (temperature, chemical reagents, etc.). Under the same conditions, the order in which the compared chemicals increased the surface area of DPACs was as follows H3PO4 > H2SO4 > ZnCl2 > K2CO3. The large surface area was contrived with DpAC58 (1753.5 m2/g) at 700 °C by H3PO4 activation. The adsorption capacity of BTEX was reached 162 mg/g at 25 °C and 1500 ppm. Consequently, the study revealed that the prepared DpAC58 from Digitalis purpurea L. biomass is suitable for the removal of BTEX from indoor air. The suggestions and prospects for future research were proposed carbon-based materials for indoor air pollutant-removal applications. [ABSTRACT FROM AUTHOR]

Hydrochars are an alternative form of biochar produced by hydrothermal carbonisation (HTC), a potentially cheaper and greener method. In this paper, the effect of multiple variables on hydrochar properties was investigated. Waste biomass was converted to hydrochar via microwave-assisted hydrothermal carbonisation. The variables were temperature, solution ratio (water-biomass ratio), time, particle size, pH and acetone washing. The measured properties were yield, carbon, oxygen and ash content, higher heating value (HHV), carbon and energy recovery and dye and water adsorption. Feedstock significance was investigated using apple, wheat, barley, oat and pea straw. The investigation into this specific combination of variables and feedstock has not been done before. HTC increased carbon content (~60%), HHV (~24 MJ/kg) and water adsorption and reduced oxygen content and dye adsorption. Thermal analysis suggested hydrochars were not suitable for sequestration. Decreasing the solution ratio was the most significant factor in increasing yield, carbon recovery and energy yield. Increasing the temperature was the most significant factor in increasing carbon and decreasing oxygen content. This affected HHV, with higher temperatures producing a higher energy material, surpassing brown coal. Hydrochars produced at a high solution ratio, temperature and times showed the best carbonisation. Smaller particle size increased yield and carbonisation but increased ash content. Low solution pH increased carbon content, HHV and water adsorption but lowered yield, carbon recovery, energy yield, dye adsorption and oxygen and ash content. High pH increased ash content and dye adsorption but lowered yield, carbon recovery, energy yield and dye adsorption. Acetone decreased yield, carbon recovery, energy yield, carbon content and HHV but increased oxygen, ash content and dye and water adsorption. Barley biomass showed the highest yield and carbon recovery, and pea showed the highest energy yield and HHV. Apple showed the highest carbon content. All the hydrochars showed promise as solid fuels, a soil additive and a precursor for activated carbon but lacked high adsorption for pollutant adsorbents and stability for carbon sequestration. [ABSTRACT FROM AUTHOR]

Carbonaceous materials are a highly appealing class of adsorbents, owing to their exceptional properties, such as high surface area and thermal and chemical stability. These materials have found successful applications in water purification. Sweet chestnut (Castanea sativa) cupules are disposed of as waste. Valorization of these residues is a step forward in terms of circular economy and sustainability. Meanwhile, per- and poly-fluoroalkyl substances (PFASs) pose significant concerns due to their persistence, bioaccumulation, and toxicity, emerging as contaminants of concern for human health and the environment. This study focuses on preparing carbonaceous material by hydrothermal carbonization from chestnut cupules, followed by their use as adsorbents for PFAS removal from polluted water. The cupule waste material was crushed, ground, sieved, and subjected to hydrothermal treatment at temperatures ranging from 180–200 °C to produce hydrothermal carbons. The adsorbents obtained were characterized by various techniques such as nitrogen adsorption isotherm, porosimetry, point of zero charge, Fourier-transform infrared, scanning electron microscopy, and thermal, elemental, and energy dispersive X-ray analyses. Surface area (SBET) values of 42.3–53.2 m2·g−1 were obtained; pHPZC ranged from 3.8 to 4.8. This study also determined the adsorption kinetics and isotherms for removing perfluorooctanoate-contaminated water. The equilibrium was established at 72 h and qe = 1029.47 mg·g−1. To summarize, this research successfully valorized a biomass residue by transforming it into hydrothermal carbon, which was then utilized as an adsorbent for water decontamination.

Reutilization of spent adsorbent by converting the adsorbed organic pollutants into carbon matrix has attracted more attention in recent years, which delivers a greener way for the preparation of catalysis and environment remediation. In this work, CuBi 2 O 4 after adsorption of pollutant sulfamethazine was further transformed to a photocatalyst CBO-WC500 with high catalytic efficiency for degradation of typical pharmaceuticals. The XAFS analysis proved that Cu-C chemical bond was constructed during the preparation process. The obtained CBO-WC500 was applied to remove sulfamethoxazole (SMX) through photocatalytic Fenton-like reaction, and removal efficiency reached 88.9 % after 60 minutes with the initial 5 mg•L−1 SMX and 0.2 g•L−1 catalyst in peroxymonosulfate (PMS) system. The results showed that the introduction of carbon stem from waste improved separation of photo-generated carriers and electron transfer capability, thus more photo-induced electrons could participate in reaction with PMS. Moreover, Cu(I) and Cu(II) in CBO-WC500 with Cu-Bi-spinel structure played a vital role in PMS activation. Led by electron transportation, reactive species (1O 2 , •OH, SO 4 •-) originated from PMS contributed to degradation of SMX, and degradation pathway of target pollutant was proposed based on analysis of intermediates. Removal efficiency of CBO-WC500 for SMX kept stable after several cycles' utilization, and it also showed decent eliminating performance of mixed pollutants in different water matrix. This study has provided a potential way for resource reuse of adsorbed pollutant and realizing reutilization of spent adsorbent as photocatalyst with higher efficiency. [Display omitted] • A novel CBO-WC500 catalyst regenerated from sulfamethazine-adsorbed CuBi 2 O 4 adsorbent. • The CBO-WC500 material exhibited high photocatalytic activating PMS capability. • Electron transfer was dominant mechanism in catalysis degradation reaction of SMX. • Mixed pollutants of four pharmaceuticals in natural water were efficiently removed. [ABSTRACT FROM AUTHOR]

A novel electrochemical sensor was developed for the determination of tyramine. The sensor was constructed by modifying the surface of a glassy carbon electrode (GCE) with a film composed of exfoliated graphite nanoplatelets (xGnPs) dispersed in a natural deep eutectic solvent (NADES). The NADES was prepared by simply mixing equimolar amounts of caprylic acid and menthol and heating at 80 °C for 30 minutes. Characterization studies confirmed the formation of a NADES through the attenuated total reflectance-Fourier transform infrared spectroscopy technique, while transmission electron microscopy demonstrated the ability of the NADES to disperse the xGnPs. Electrochemical impedance spectroscopy data showed that the modified sensor exhibited lower resistivity than the unmodified electrode. By optimizing the parameters of square wave voltammetry and experimental conditions to obtain the highest peak current values for tyramine oxidation, a calibration curve was constructed in a 0.1 mol L−1 phosphate buffer (pH 7.0), obtaining detection and quantification limits of 0.06 and 0.20 mg L−1, respectively. Finally, the sensor was successfully applied to the determination of tyramine in fermented milk, beer, and non-alcoholic beer samples, with satisfactory recovery data. [Display omitted] • NADES was prepared by a mixture of caprylic acid and menthol. • NADES acted as a dispersing agent for exfoliated graphite nanoplatelets (xGnPs). • The xGnP-NADES reduced resistance to charge transfer compared to a bare GCE. • The sensor demonstrated satisfactory results in the determination of tyramine. [ABSTRACT FROM AUTHOR]

Nowadays, global warming is mainly caused by increase in CO2 concentration in the environment; to mitigate this problem, an attractive strategy for efficient CO2 emission reduction was applied: carbon capture. Therefore, this work had as main objective to measure the capture of CO2, through two carbonaceous materials produced from sugar cane bagasse; this biochar was activated chemically with KOH, by two different processes: the impregnated biochar (CA-1) was taken to pyrolysis process at 350 °C and another sugarcane bagasse sample was also impregnated, but directly in dry biomass (CA-2), obtaining two carbonaceous material (CA-1 and CA-2), respectively. The prepared carbons were characterized by thermal analysis with heating rate of 10 °C min−1 in N2 atmosphere, showing two main stages: the first one close to 150 °C for biochar samples and the second one in the range of 150–600 °C for the same biochar samples, X-ray diffraction (XRD, peaks at 2θ = 28.41°; 40.50°; 44.52°; 50.29° and 58.61° for CA-1 and 2θ = 28.27°; 40.45°; 44.60°; 50.15° and 58.63° for CA-2), scanning electron microscopy (SEM) with energy-dispersive X-ray (EDX) and Fourier transform infrared spectroscopy (FTIR, showing peaks at 3675, 2926, 1559, 1364, 1026 and 916 cm−1 for the biochar samples). CO2 capture was performed by thermogravimetric running test. The samples showed similar physico-chemical characteristics, but the CA-2 sample showed better adsorption performance (1.22 mmol CO2 g−1). Heat treatment in an inert atmosphere and chemical activation of biomass are recommended for obtaining carbonaceous material for use in carbon dioxide adsorption processes. [ABSTRACT FROM AUTHOR]

The developed simple mesoporous Ar-G-CM/SiO 2 composite with multiple hydrogen bond donor groups presented good to excellent catalytic activity to the CO 2 cycloaddition with various epoxides under metal-absent and solvent-free conditions. [Display omitted] • TAr-G-CM/SiO 2 catalyst presented efficient catalysis for CO 2 cycloaddition. • The efficient catalysis was originated from HBD groups and mesoporous structure. • The synthesis for catalyst was a green route without toxic solvent use. In this paper, a novel arginine-glucose derived carbonaceous-material-loaded SiO 2 composite catalyst (Ar-G-CM/SiO 2) was synthesized from non-toxic and harmless reagents (arginine, glucose and tetraethylorthosilicate) by simple hydrothermal process. Mesoporous SiO 2 with high specific area served as support for carbonaceous material and provided extra hydrogen bond donor (HBD) groups. Ar-G-CM/SiO 2 with acid-base dual functional groups (COOH, NH 2) and HBD group (OH) presented 62% yield and 99% selectivity to product of propylene carbonate in CO 2 cycloaddition reaction with propylene oxide even at 40 °C, 2 MPa under metal-absent and solvent-free conditions. For some less active epoxides with steric hindrance, Ar-G-CM/SiO 2 also showed good yield and selectivity over 90% by raising temperature to 120 °C. Furthermore, the Ar-G-CM/SiO 2 catalyst could be reused for six successive cycles without significant decrease in catalytic activity or structural deterioration, because the carbon deposition was restrained owing to the mesoporous structure of the catalyst. [ABSTRACT FROM AUTHOR]

Summary: This study introduces a simple and eco‐friendly synthetic strategy for yolk‐shell nanospheres that consist of manganese selenide yolks and carbon shells (MnSe@C) by reacting manganese salt impregnated in the porous hollow carbon nanospheres (HCNS) with H2O vapor. First, manganese salt dissolved in ethanol was impregnated into the spacious pores of the HCNS by capillary force. Then, heat treatment of the powder in the presence of H2O triggered the nucleation and crystal growth of manganese hydroxide, resulting in the formation of HCNS whose central voids are filled with multiple nanoparticles. Subsequent selenization yielded yolk‐shell nanospheres with MnSe@void@carbon configuration. MnSe@C was applied as the anode for sodium‐ion batteries (SIBs), and the following electrochemical reaction was confirmed from various analytical techniques: MnSe +2Na+ + 2e− ↔ Mn + Na2Se. MnSe@C nanospheres exhibited stable cycle performance up to 1000 cycles at 0.5 A g−1, wherein a reversible capacity of 222 mA h g−1 was delivered in the 1000th cycle. Furthermore, MnSe@C nanospheres exhibited a fair rate performance (209 mA h g−1 at 2.0 A g−1). [ABSTRACT FROM AUTHOR]

A unique "integrated hard-templating strategy" is developed for facile synthesis of a carbonaceous material with a novel three-dimensional (3D) branched hollow architecture. The controlled complexity of hollow structures can provide exceptional performance and unconventional advantages. [Display omitted] A unique "integrated hard-templating strategy" is described for facile synthesis of a carbonaceous material with a novel three-dimensional (3D) branched hollow architecture. A set of steps, including template formation, surface coating and template removal, all occur in a spontaneous and orderly manner in the one-pot hydrothermal process. Investigations on structural evolution during the process reveal that pre-synthesized zeolitic imidazolate framework-8 (ZIF-8) nanoparticles are first dissociated and then self-assembled into 3D branched superstructures of ZnO as templates. Initial self-assembly is followed by coating of the glucose-derived carbonaceous materials and etching of interior ZnO by organic acids released in situ by hydrolysis of glucose. The 3D-branched hollow architecture is shown to greatly enhance supercapacitor performance. The research described here provides guidance into the development of strategies for complex hollow carbonaceous architectures for a variety of potential applications. [ABSTRACT FROM AUTHOR]

Phenolic compounds (PhCs) are ubiquitously distributed phytochemicals found in many plants, body fluids, food items, medicines, pesticides, dyes, etc. Many PhCs are priority pollutants that are highly toxic, teratogenic, and carcinogenic. Some of these are present in body fluids and affect metabolism, while others possess numerous bioactive properties such as retaining antioxidant and antimicrobial activity in plants and food products. Therefore, there is an urgency for developing an effective, rapid, sensitive, and reliable tool for the analysis of these PhCs to address their environmental and health concern. In this context, carbonaceous nanomaterials have emerged as a promising material for the fabrication of electrochemical biosensors as they provide remarkable characteristics such as lightweight, high surface: volume, excellent conductivity, extraordinary tensile strength, and biocompatibility. This review outlines the current status of the applications of carbonaceous nanomaterials (CNTs, graphene, etc.) based enzymatic electrochemical biosensors for the detection of PhCs. Efforts have also been made to discuss the mechanism of action of the laccase enzyme for the detection of PhCs. The limitations, advanced emerging carbon-based material, current state of artificial intelligence in PhCs detection, and future scopes have also been summarized.

Carbonaceous material undergoes changes in its maturity mainly in response to its thermal history. Among the various geothermometers based on Raman spectra of carbonaceous material, those proposed by Kouketsu et al. (2014) have been employed to investigate the temperatures experienced by terrestrial rocks that undergo low‐ to medium‐grade metamorphism. Although their geothermometers use spectral parameters that can be determined only by peak deconvolution, criteria for setting the initial conditions for nonlinear least‐squares fitting have not been specified, which may generate unnecessary errors in the estimated temperatures owing to differences in fitting results among data analysts. To address this issue, we developed a code that automatically calculates the parameters required for the geothermometers of Kouketsu et al. (2014); that is, the widths of the D1‐ and D2‐bands. Our code yields parameter values consistent with those of Kouketsu et al. (2014) for the same Raman data and is applicable to datasets other than those used to develop it. The geothermometers based on the obtained results show a comparable performance to Kouketsu et al. (2014). Errors in the estimated temperatures caused by variation in Raman systems and the subjective selection of the fitting method are smaller than the uncertainties of the geothermometer itself, so long as the temperature is calculated by following the procedures of the present study. Although this study focused only on geothermometers that require peak deconvolution, the development of those based on fitting‐free Raman parameters and on the reaction kinetics of carbonaceous material should be investigated in future studies. [ABSTRACT FROM AUTHOR]

This work focuses on the natural graphitic carbonaceous material (GCM) distributed in metasedimentary and crystalline rocks in and around Larji–Rampur tectonic window, Himachal Himalaya. The GCM, associated with the ore mineralization, is mostly flaky, however, it is also granular and amorphous. The micro Raman spectroscopy of representative samples confirms that the studied GCM is mostly disordered graphite and rarely poorly ordered graphite, but well crystalline ordered graphite is also present. The carbon isotope compositions reflecting the source of carbon in GCM at various locations attribute that the carbon was mostly sedimentary organic carbon which has been metamorphosed to disordered graphite, however, the δ13C of the inorganic carbon contents in metabasalts from Bhallan signify the involvement of fluid possibly derived from the mantle. Limited δ13Cinorganic data in a range from 0 to −11‰, points to the heavier carbon probably derived from the diagenetic carbonates or dissolved organic matter. Overall, the carbon isotope compositions of GCM from the Larji–Rampur window reflect diversity in carbon source and mixing of carbon reservoirs, which can adequately be explained by the Proterozoic marine carbon cycling. A close linkage in the depositional processes of GCM with ore mineralization in the area is also invoked. Research Highlights: The graphitic carbonaceous material (GCM) is present in and around Larji–Rampur tectonic window, Himachal Himalaya, at places associated with ore mineralization. Micro Raman spectroscopy confirms the presence that this GCM is mostly disordered graphite though the ordered graphite is also present uncommonly. The δ13C values vary widely from –1.5‰ to –33.5‰. The δ13C compositions are heterogeneous and complex carbon systematics is apparent. In addition to the predominant sedimentary organic carbon form Proterozoic marine carbon, it was also derived from carbonate source, carbon from the fluids, and rarely but possibly from the mantle source. A close linkage in the formation and evolution processes of the GCM with the ore mineralization is also invoked. [ABSTRACT FROM AUTHOR]

Since the observation that carbon materials can facilitate electron transfer between reactants, there is growing literature on the abiotic reductive removal of organic contaminants catalyzed by them. Most of the interest in these processes arises from the participation of carbon materials in the natural transformation of contaminants and the possibility of developing new strategies for environmental treatment and remediation. The combinations of various carbon materials and reductants have been investigated for the reduction of nitro‐organic compounds, halogenated organics, and azo dyes. The reduction rates of a certain compound in carbon‐reductant systems vary with the surface properties of carbon materials, although there are controversial conclusions on the properties governing the catalytic performance. This review scrutinizes the contributions of quinone moieties, electron conductivity, and other carbon properties to the activity of carbon materials. It also discusses the contaminant‐dependent reduction pathways, that is, electron transfer through conductive carbon and intermediates formed during the reaction, along with possibly additional activation of contaminant molecules by carbon. Moreover, modification strategies to improve the catalytic activity for reduction are summarized. Future research needs are proposed to advance the understanding of reaction mechanisms and improve the practical utility of carbon material for water treatment. Practitioner points: Reduction rates of contaminants in carbon‐reductant systems and modification strategies for carbon materials are summarized.Mechanisms for the catalytic activity of carbon materials are discussed.Research needs for new insights into carbon‐catalyzed reduction are proposed. [ABSTRACT FROM AUTHOR]

This study investigates the microwave absorption properties of polyaniline (PAni) with varying carbonaceous material, CM (Fullerene,C60) contents. PAni nanocomposites were prepared with varying contents of C60 ranging from 5 to 40% through a chemical oxidation method by using carboxylic acid as the dopant. The functional groups of PAni nanocomposites were validated by Fourier Transform Infrared Spectroscopy (FTIR) and Ultraviolet–visible (UV–Vis) Spectroscopy analyses. The surface morphology of nanocomposites and the presence of titanium dioxide (TiO2) and C60 were confirmed by Field Emission Scanning Electron Microscopy (FESEM) and X-ray Diffractometry (XRD), respectively. Microwave absorption studies were carried out using Microwave Vector Network Analyzer (MVNA) from 0.5 to 18.0 GHz. The study showed that PAni nanocomposites with 10% of C60 formed the nanorods/nanotubes with the biggest diameter of 200 nm as compared to other PAni nanocomposites. It was found that PAni nanocomposites with 10% C60 also recorded the highest electrical conductivity and relative permittivity of 1.708 × 10–1 S/cm and 9.97, respectively. The nanocomposite that was formulated with 10% of C60 showed an improvement of interchain and intrachain charge transfer as well as molecular polarization along the PAni backbone. Hence, it eventually reduces the electrical energy dissipated by PAni, and finally enhances the microwave absorption properties with the highest reflection loss (RL) of −61.3 dB at 9 GHz. [ABSTRACT FROM AUTHOR]

Hydrochar is a carbonaceous material that is generated through the process of hydrothermal carbonization (HTC) from biomass, which has garnered considerable attention in recent years owing to its potential applications in a diverse range of fields, such as environmental remediation and agriculture. Hydrochar is produced from a diverse range of biomass waste materials and retains exceptional properties, including high carbon content, stability, and surface area, making it an optimal candidate for various enviro-agricultural applications. Moreover, it delves into the production process of hydrochar, with explicit emphasis on the optimization of certain properties during the production of hydrochar from bio-waste. Furthermore, the potential of hydrochar as an adsorbent and catalyst support for heavy metals and dyes was extensively explored, along with a soil remediation potential that can improve the physical, chemical and biological properties of soil. This comprehensive review aims to provide a thorough overview of hydrochar with a particular focus on its production, properties, and prospective applications. The significance of hydrochar is accentuated and the growing need for alternative sources of energy and materials that are environmentally sustainable is highlighted in this paper. Besides, the consequence of hydrochar on soil properties such as water-holding capacity, nutrient retention, and total soil porosity, as well as its influence on soil chemical properties such as cation exchange capacity, electrical conductivity, and surface functionality is scrutinized. [Display omitted] [ABSTRACT FROM AUTHOR]

Carbonaceous materials as well as its form functionalized with metallic silver have been prepared by hydrothermal carbonization of fructose. Results are presented to show that nanostructured silver was obtained through the functionalization process. The carbonaceous materials were characterized by: nitrogen adsorption/desorption measurement, XRD, SEM/EDS and FTIR. Samples functionalized with silver were analyzed by: XRD and SEM/EDS. The XRD analysis showed that the carbonaceous materials functionalized with silver by hydrothermal carbonization process were successfully performed. Size of silver particles was found to be approximately 32 nm, indicating formation of nanostructure. All samples were tested as an antimicrobial agent for water disinfection. Presence of nanostructured silver in the sample containing 1 mg/mL carbonaceous materials significantly decreased the number of CFU (dCFU = 97.33 %) if compared to the same sample containing the same amount of carbonaceous materials but without of silver (dCFU 65.33 %). [Projects of the Serbian Ministry of Education, Science and Technological Development, Grant no. III45005, Grant no. 173049 and Grant no. 172015]