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Ionogels (IGs) consisting of ionic liquids (ILs) confined in carbon and organic polymer matrices have recently emerged as promising materials for electrochemical systems. This perspective article explores how the structural, dynamic, and thermodynamic properties of ILs are modified by their confinement. It emphasizes the importance of combining various ILs and matrices to enhance IG properties through IL‐matrix interactions. Specifically, it highlights the significant downshift of IL melting point observed in certain porous carbons, as well as the enhanced ionic conductivity at sub‐ambient temperature in polymer networks. Accordingly, the suitability of these IGs for use in electrochemical systems operating at low temperature is discussed. Although significant progress has been made in the development and applications of carbon and polymer IGs, it is necessary to further explore the texture/structure of real host matrices, which may differ from model ones. Investigating the low‐temperature mobility of ions in IG‐based electrodes with micro/mesoporous carbons is an example of unexplored research area that may open new opportunities for increasing the energy and power density in energy storage applications. The suggested directions should facilitate innovative solutions to current and future challenges for electrochemical systems across a wide temperature range from −40 to 200 °C. [ABSTRACT FROM AUTHOR]

In this research, the microstructure of three melt‐spinning ribbons with a weight‐based composition of Fe–25Cr–5Ni and varying carbon contents (0.02, 0.10, and 0.38 wt%) is evaluated. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are used for microstructural characterization. SEM analyses consist of image acquisition and electron backscatter diffraction. TEM analyses consist of bright‐field image acquisition, selected area electron diffraction, high‐resolution TEM, and local chemical composition measurements by energy‐dispersive X‐ray spectrometry. According to the results, the ribbons show different microstructures resulting from different solidification paths. The ribbon containing 0.02%C presents a predominantly ferritic microstructure, and austenite solid‐state precipitation is not suppressed. It occurs as grain‐boundaries allotriomorphs and secondary Widmanstätten side plates. As a result of carbon additions, the ribbon containing 0.10%C shows a microstructure composed of nearly equal parts ferrite and austenite, along with M23C6 (M = Cr15.6Fe7.4) nanometric carbides. The cube‐on‐cube orientation relationship is found between M23C6 and austenite. Lastly, the ribbon containing 0.38%C exhibits austenitic microstructure with islands of ferrite surrounded by M7C3 (M = Cr4.14Fe2.86) carbides. [ABSTRACT FROM AUTHOR]

Given the pressing climate and sustainability challenges, shifting industrial processes towards environmentally friendly practices is imperative. Among various strategies, the generation of green, flexible materials combined with efficient reutilization of biomass stands out. This review provides a comprehensive analysis of the hydrothermal carbonization (HTC) process as a sustainable approach for developing carbonaceous materials from biomass. Key parameters influencing hydrochar preparation are examined, along with the mechanisms governing hydrochar formation and pore development. Then, this review explores the application of hydrochars in supercapacitors, offering a novel comparative analysis of the electrochemical performance of various biomass-based electrodes, considering parameters such as capacitance, stability, and textural properties. Biomass-based hydrochars emerge as a promising alternative to traditional carbonaceous materials, with potential for further enhancement through the incorporation of extrinsic nanoparticles like graphene, carbon nanotubes, nanodiamonds and metal oxides. Of particular interest is the relatively unexplored use of transition metal dichalcogenides (TMDCs), with preliminary findings demonstrating highly competitive capacitances of up to 360 F/g when combined with hydrochars. This exceptional electrochemical performance, coupled with unique material properties, positions these biomass-based hydrochars interesting candidates to advance the energy industry towards a greener and more sustainable future. [ABSTRACT FROM AUTHOR]

Tanned leather is a product of high intrinsic value and a sign of luxury. Chromium-tanned leather shavings are abundantly produced wastes which contain chromium that could be revalorized. The present research proposes the use of alkaline hydrolysis, aided by an inorganic anion, to promote the hydrolysis of the Cr–O bond. De-chromed solids were employed to synthesize carbon material, which subsequently was applied for dye removal from aqueous solution, while the chromium-rich solution was used as a re-tanning agent. The results demonstrated that it is possible to develop a method of chromium-protein separation, with a minimum degree of hydrolyzation. When an activating agent was employed, the prepared carbon had a surface area of 585 m2/g, with trace levels of chromium (< 0.1%), present mainly as Cr2O3 particles. The materials displayed an adsorption capacity of up to 47.60 mg/g and 27.58 mg/g for methylene blue and Congo red respectively. The chromium-rich solution contained proteins and amino acids that aid in its employment as a re-tanning agent. Leather that was re-tanned with this solution had a similar tear strength and a superior and tensile strength (38%), superior elongation at break (10%), and improved elongation at break (47%) than traditional Cr33-tanned leather. The present study represents a major step in the development of cleaner production of leather. [ABSTRACT FROM AUTHOR]

Despite notable achievements in the development and application of the remediation of metal-contaminated soils, the search for and study of promising immobilizing agents continues. This article presents a new approach to using brown coal and activated carbon and their application for metal stabilization. An experiment was conducted to test Medicago falcata L. on soils from industrial areas contaminated with varying levels of lead (Pb), cadmium (Cd), chromium (Cr), zinc (Zn), copper (Cu), and nickel (Ni) with the addition of carbons. This plant is a stress-tolerant leguminous species. In this study, the total content of metals in soil and the available forms to plants (single extractions with 0.02 M ethylenediaminetetraacetic acid, EDTA) were determined, along with metal contents in the plant. The use of carbons lowered the phytoavailable forms of metals for plants and thus, resulted in a reduction in the phytotoxicity of the soils. The contents of the tested metals in the roots and shoots were lower than in the combinations of soils with no carbon added. The activated carbon had a stronger effect on limiting the availability of metals than brown coal in relation to plants growing on soils without added carbon; the percentage of reduction for the shoots was Cr (18.2%) > Zn (11.5%) > Ni (10.7%) > Cu (10.3%) > Cd (8.9%) > Pb (2.4%) and Cu (13.3%) > Cr (12.5%) > Zn (10.5%) > Pb (9.0%) > Ni (5.7%) > Cd (4.6%) for roots. Metals reduced the growth of Medicago falcata L. roots from 44 to 21%, while the growth of shoots was reduced from 25 to 2%. Adding carbons to soils in all combinations resulted in a decrease in the following pollution indices: pollution index (PI), pollution load index (PLI), and non-carcinogenic (HQ) and carcinogenic risk factors (ILCR). [ABSTRACT FROM AUTHOR]

The incorporation of carbon materials in batteries serves to enhance its performance by improving conductivity, achieving uniform active material distribution, increasing capacity, mitigating sulfation, extending cycle life, and considering potential environmental benefits. Even though several possible mechanisms were reported, how exactly carbon works is not fully understood. In the present study a new form of carbon black was prepared from Ageratina adenophora (CBAa) and investigated for its impact on the electrical conductivity of the negative active material in 2 V lead acid cell. The performance was compared with other commercially available carbons like Graphite PG-10, Carbon N550, Carbon N330 and Carbon Vulcan. The carbon was characterised by XRD, SEM and grain size analysis. The initial capacity of the cell was consistently higher and remained stable at 4.6 W∙h; in the life cycle analysis, the cells showed 290 cycles. The post-life cycle test analysis showed that only a white layer on multiple plates indicating the onset of sulfation and there is no corrosion. The performance of the CBAa prepared in the present work was found to be better when compared with the commercially available carbons.

Sodium-ion batteries (SIBs) are promising alternatives to replace lithium-ion batteries as future energy storage batteries because of their abundant sodium resources, low cost, and high charging efficiency. In order to match the high energy capacity and density, designing an atomically doped carbonous material as the anode is presently one of the important strategies to commercialize SIBs. In this work, we report the preparation of high-performance dual-atom-doped carbon (C) materials using low-cost corn starch and thiourea (CH4N2S) as the precursors. The electronegativity and radii of the doped atoms and C are different, which can vary the embedding properties of sodium ions (Na+) into/on C. As sulfur (S) can effectively expand the layer spacing, it provides more channels for embedding and de-embedding Na+. The synergistic effect of N and S co-doping can remarkably boost the performance of SIBs. The capacity is preserved at 400 mAh g −1 after 200 cycles at 500 mA g−1; more notably, the initial Coulombic efficiency is 81%. Even at a high rate of high current of 10 A g−1, the cell capacity can still reach 170 mAh g−1. More importantly, after 3000 cycles at 1 A g−1, the capacity decay is less than 0.003% per cycle, which demonstrates its excellent electrochemical performance. These results indicate that high-performance carbon materials can be prepared using low-cost corn starch and thiourea. [ABSTRACT FROM AUTHOR]

Despite notable achievements in the development and application of the remediation of metal-contaminated soils, the search for and study of promising immobilizing agents continues. This article presents a new approach to using brown coal and activated carbon and their application for metal stabilization. An experiment was conducted to test Medicago falcata L. on soils from industrial areas contaminated with varying levels of lead (Pb), cadmium (Cd), chromium (Cr), zinc (Zn), copper (Cu), and nickel (Ni) with the addition of carbons. This plant is a stress-tolerant leguminous species. In this study, the total content of metals in soil and the available forms to plants (single extractions with 0.02 M ethylenediaminetetraacetic acid, EDTA) were determined, along with metal contents in the plant. The use of carbons lowered the phytoavailable forms of metals for plants and thus, resulted in a reduction in the phytotoxicity of the soils. The contents of the tested metals in the roots and shoots were lower than in the combinations of soils with no carbon added. The activated carbon had a stronger effect on limiting the availability of metals than brown coal in relation to plants growing on soils without added carbon; the percentage of reduction for the shoots was Cr (18.2%) > Zn (11.5%) > Ni (10.7%) > Cu (10.3%) > Cd (8.9%) > Pb (2.4%) and Cu (13.3%) > Cr (12.5%) > Zn (10.5%) > Pb (9.0%) > Ni (5.7%) > Cd (4.6%) for roots. Metals reduced the growth of Medicago falcata L. roots from 44 to 21%, while the growth of shoots was reduced from 25 to 2%. Adding carbons to soils in all combinations resulted in a decrease in the following pollution indices: pollution index (PI), pollution load index (PLI), and non-carcinogenic (HQ) and carcinogenic risk factors (ILCR).

Synthesis and characterization of structure magnetic properties of Fe3O4@ZnO- C nanocomposite have been done through the precipitation method. This study aimed to discover the effect of concentrations/thickness of carbon layer on crystal structure and magnetic properties of Fe3O4@ZnO-C nanocomposites. Fe3O4 and Fe3O4@ZnO were the samples used in the study, and variations in the amount of carbon were 0.2, 0.1, and 0.05 g. Nanocomposites were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and vibrating sample magnetometer (VSM). Based on the results of XRD, it has been found that the crystal structure for Fe3O4 was cubic, while ZnO was hexagonal wurtzite. The addition of carbons to Fe3O4@ZnO caused a broadening of the diffraction peaks and a decrease in the degree of crystallinity. The bonds formed on Fe3O4@ZnO-C nanocomposites, i.e. Fe-O bonds indicated the formation of Fe3O4, Zn-O bonds showed the formation of ZnO and C-O, C-H, and O-H bonds revealed the presence of a carbon layer originated from glucose. The VSM results showed that the magnetic saturation decreased with increasing carbon mass. Overall, the carbon-coated nanocomposite material with a carbon mass variation of 0.2, 0.1, and 0.05 g showed superparamagnetic properties with a magnetic saturation of 18.23 emu/g, 19.33 emu/g and 22.05 emu/g, while for the coercive field of 92.29 Oe, 92.90 Oe and 89.60 Oe, respectively. Based on these characterization results, Fe3O4@ZnO-C nanocomposite materials can potentially be developed as biomedical materials, such as the materials for photothermal therapy for cancer cells.

In the current state of the art, textile products and materials generate a significant environmental impact since they are not managed under a circular economy paradigm. It is urgent to define new sustainable paths in the textiles industry by setting up materials, technologies, processes, and business models to reuse and recycle textiles production waste and End-of-Life textiles. In this direction, taking advantage of textile-related materials, especially from renewable and waste resources, for depollution purposes appears very promising since it enables re-use, but it also supports secondary applications with a high sustainability impact. This review collects and describes possible adsorption, filtration and purification capabilities of (i) various functionalized textiles, (ii) biopolymers constituting the natural fibers (cellulose, keratin, fibroin) and (iii) textile-derived active carbons and biochar, in order to provide a structured framework for the systemic exploitation of the depollution potential of waste textiles. The correlations among the type of textile materials, the physical-chemical treatments, and the characteristics influencing the performances of such materials as decontaminating tools will be underlined. [ABSTRACT FROM AUTHOR]

Carbon materials produced by solution plasma process (SPP) typically exhibit insufficient surface area and deficient microporosity, limiting their application in supercapacitor electrodes. Thus, post-engineering strategies are necessary to overcome this limitation. In this study, carbon nanoparticles (CNPs) were synthesized from benzene by SPP and subsequently subjected to thermal air treatment (TAT) under mild conditions (300 and 400 °C in an air atmosphere). The resulting CNPs had uniform morphology and an amorphous structure. With increasing TAT temperature, the specific surface area of CNPs increased from 171 to 575 m2 g−1 through the development of micropores and mesopores. TAT also enriched the acidic oxygen functional groups on the surfaces of the CNPs. The electrochemical charge storage properties of the CNPs were investigated using a three-electrode system in a 1 M H2SO4 electrolyte. The CNPs with TAT at 400 °C demonstrated the highest specific capacitance of 130 F g−1 at a current density of 1 A g−1, which was 5.4 times higher than that of the untreated CNPs (24 F g−1). It also exhibited stable cycling performance after 5000 charge–discharge cycles. This study demonstrates that TAT is a simple and effective post-engineering strategy for increasing the specific surface area and micro–mesoporosity of SPP-derived CNPs, as well as modifying their surface chemistry. These improvements enable the practical application of CNPs produced by SPP in the field of supercapacitors.

After being undervalued for a long-time, the potential use of lignins have gained interest as a source of wealth from waste. Despite the complexity of lignins chemical structure, its high carbon content compared to cellulose and sugars makes lignin a very promising precursor for the development of nanocarbons for broad range applications, including supercapacitors for energy storage. High performing supercapacitors have been made using dimensionally different nanocarbon entities (zero-to three), such as carbon nanoparticles, carbon nanodots, carbon fibers, and carbon nanosheets with modular and interconnected pore structures, which are prepared from lignins of various types with and without use of templates, porogens and chemical agents. Control of physicochemical and electrochemical properties in such nanocarbons remains the key for their high energy density, flexibility, and long-term stability. To this end, nanocarbons conductivity, porosity and surface areas are controlled by various synthesis approaches while detailed adjustment of pore structure, pore width and pore distribution have been made to improve electrolyte access, ions confinement, and transportation. To compare performances of nanocarbons made from different lignin types, we must do meaningful investigations on the lignin's structure, composition, and purity to understand how their structure-property relationships are influenced by pyrolysis, carbonization and activation methods/conditions used. In this review, a clear overview of the lignins structure, classification, and properties is presented, wherein we compared the structure-property-performance relationships of nanostructured carbons from lignins for improvement of supercapacitor device performances with recent advances. Separation processes of lignin from wood, steps involved in preparing dimensionally different nanocarbon entities (zero -to three), and electrolytes for the fabrication of sustainable and flexible supercapacitor devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Soil quality in urban areas in India is degraded due to multiple anthropogenic activities. The objectives of this work are to determine the concentration variations, toxicity, and sources of carbons, metals, and ions in the surface soil of Raipur, the industrialized capital city of Chhattisgarh state, India. High concentrations of Al, K, Ca, Ti, Fe, and elemental carbon (EC) were registered. Relatively lower concentrations of V, Cr, Mn, Ni, Cu, Zn, Sr, Ba, Pb, organic carbon (OC), and carbonate carbon (CC), as well as ions (viz. F–, Cl–, NO3–, SO42–, Na+, K+, Mg2+, and Ca2+), were also recorded. EC was found to be one of the major pollutants, although enrichment factors pointed to high contamination with SO42–, K+, Mg2+, Cr, Mn, and Pb; and extreme contamination with NO3– and Ca2+. The spatial and temporal variations, enrichment factors, toxicity, and sources of the chemical species detected in the soil are discussed. [ABSTRACT FROM AUTHOR]

Pollution associated with polycyclic aromatic hydrocarbons (PAHs) and carbon emissions, resulting from fossil fuel combustion, is a matter of major concern in India. In this work, the distribution, variations, sources and fate of twelve PAHs (phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene, benzo[ghi]perylene and indeno[1,2,3-cd]pyrene) and carbonaceous particulate matter (elemental/black carbon (EC/BC), organic carbon (OC) and inorganic/carbonate carbon (CC)) in the air, road dust and sediments of three cities in the most industrialized area of Central India (Chhattisgarh state) are reported. The PM and road dust/sediment samples were collected by using a low volume air sampler and a stainless–steel scoop, respectively. PAHs were extracted into organic solvents and the dried residue was dissolved into acetonitrile for analysis. Carbons and PAHs were analyzed by thermal and chromatographic methods. Concentrations of particulate matter (PM10), total carbon (TC = EC + OC + CC) and total polycyclic aromatic hydrocarbons (∑12PAHs) of 116–523 µg m−3, 22.1–179.6 µg m−3 and 37.7–164.9 ng m−3, respectively, were found in air at the beginning of the study (2007/08). Concentrations of 6.02 − 9.87% (TC) and 8689 − 87458 ng g−1 (Σ12PAHs) were detected in road dust, while relatively lower concentrations were observed in sediments, in the 4.99–10.78% and 4721–11768 ng g−1 range, respectively. Regarding monthly and seasonal variations, the highest PAHs and TC concentrations occurred in December/January and in the winter season. Spatial (residential, commercial, and industrial areas) and temporal (2008-2015) variations of these pollutants are also discussed, together with their source apportionment based on factor analysis. Given that benzo[a]pyrene and ∑12PAHs concentrations clearly exceed the permissible limits, and that the concentration of PAHs in dust for one of the three cities under study (Bhilai) is the highest reported in the literature, this study shows the urgent need for continuous monitoring of organic aerosol constituents in the ambient air of the cities in this region. [ABSTRACT FROM AUTHOR]

[Display omitted] • Recent developments on Pd-based electrocatalysts towards ethanol oxidation reaction (EOR) have been reviewed. • High-entropy and single-atom catalysts are viable integrants with Pd nanoparticles for enhanced EOR. • New carbons, onion-like carbons, and MXenes are emerging alternative supporting platforms for Pd-based catalysts for EOR. Alkaline direct ethanol fuel cells (ADEFCs) offer a promising solution to reduce reliance on fossil fuels. Despite their advantages over hydrogen and methanol fuel cells, the anodic ethanol oxidation reaction (EOR) in ADEFCs faces challenges such as sluggish kinetics and high overpotentials, leading to reduced efficiency. To address these issues, highly active electrocatalysts are essential. This review highlights recent advancements in Pd-based high-entropy materials (HEMs) and single-atom catalysts (SACs) for EOR. Additionally, MXenes, a novel family of two-dimensional materials, have shown promise as supports for these electrocatalysts. We discuss the fundamental principles of EOR, the unique properties of these emerging materials, and their applications in EOR electrocatalysis. Finally, we provide an outlook on future research directions to enhance the commercialization of Pd-based electrocatalysts for ADEFC technologies. [ABSTRACT FROM AUTHOR]

The search for room-temperature superconductivity in carbons is gathering momentum because it has a long history, impressive track record, clear advancement route, and theoretical backup. The report of a suspected Josephson current in Al-C-Al sandwiches at room temperature, published in Nature 50 years ago, led to the report of a voltage in nano-graphite films believed to mark the reverse Josephson effect. The report on oxygen-doped diamonds led to full-blown superconductivity in boron-doped diamonds. The reports on highly oriented pyrolytic graphite (HOPG) and water-treated graphite powder led to the claim of a current running by itself for 50 days in a ring of HOPG soaked with alkane at room temperature. It also led to a claim of a current running for 1,000 seconds in a ring of graphene soaked in hexane. The carbons are amicable to intercalation chemistry, electrostatic carrier doping, and surface-proving techniques to promote an increase in carrier density, metallization, and applicability of the Ashcroft proposal. Consequently, the high Debye temperatures (1,670, 2,230 and 2,500 K in graphene, diamond and HOPG) may be sufficient to underwrite superconductivity at T ∼ 300 K in carbons, provided the phonon-exchange factor, λ , is around 3 to mark strong enough interactions between electrons and phonons. • The long history of the pursuit. • Early reports and impressive track record. • Clear advancement route of pursuit. • The theoretical backup. [ABSTRACT FROM AUTHOR]

We compare the electrochemical response and intrinsic limitations of symmetric carbon-based supercapacitors using two 3D-printing techniques, vat polymerization (Vat-P) and fused deposition modelling (FDM). Two cell types were made in this study, one with metallized Vat-P-printed current collectors, the other with PLA (polylactic acid) FDM-printed current collectors in a similarly designed printed coin cell. Carbon-based electrode slurry (various combinations of SWCNT, GNP, Super-P, PVDF) and aqueous 6 M KOH electrolyte were used in these cells. We demonstrate the influence of internal resistance of each 3D-printing method by direct comparison of cyclic voltammetry and galvanostatic charge-discharge tests. The metallized conductive Vat-P cells display better conductivity and more ideal rectangular cyclic voltammetry response but suffer from poor cycle life in initial experiments (∼5,000 charge-discharge cycles before losing all specific capacitance). The FDM current collector cells using graphite-containing PLA materials have poorer conductivity, less ideal cyclic voltammetry curves, and are structurally less robust and partially porous, but offer very stable cycle life for supercapacitor cells retaining most of their specific capacitance after 100,000 charge-discharge cycles. The cycle life of the metallized Vat-P cells are improved by reducing the voltage window to 0.2–0.7 V to limit metal delamination and using Super-P and PVDF additives.

Abstract Hard carbons are widely studied as anode materials for sodium‐ion batteries (SIBs) due to their high Na‐storage capacity, long cycle life, and low cost. However, the low initial coulombic efficiency (ICE) and poor cycle performance remain bottleneck concerns that necessitate a comprehensive material engineering solution. Herein, we propose a facile strategy to synthesize amorphous carbons with pseudo‐graphitic dominated crystalline, expanded interlayer spacing, and reduced surface defects via carbonization of the cross‐linking network of phenolic resin and sucrose. An elaborate structural and electrochemical characteristics analysis has been investigated against different sucrose contents and carbonization temperatures. The representative PF‐S‐55‐1200 with the optimum cross‐linking degree as well as carbonization temperature realizes a high reversible Na‐storage capacity of 323.0 mAh g−1 with an ICE as high as 86.4%, much superior to the pristine phenolic resin pyrolytic carbon with a capacity of 267.1 mAh g−1 and an ICE of 46.3%. The hybrid hard carbons also exhibit robust structural stability with a prolonged cycle lifespan evidenced by a retained capacity of 238.3 mAh g−1 at a current density of 200 mA g−1 over 1500 cycles. The proposed route promises low‐cost and high‐performance hybrid hard carbons with optimized structural configuration for advanced SIBs.

Magnetosensitive biochars were prepared with mechanochemical ball-milling of lignin and blast furnace dust with further pyrolysis at 800 °C under an inert gas atmosphere. The physicochemical and sorption characteristics of the materials were analyzed using several techniques: low-temperature nitrogen adsorption–desorption, X-ray powder diffraction, Raman spectroscopy, elemental analysis, potentiometric titration, and thermal analysis. All the synthesized biocarbons were characterized by their specific surface areas (SBET) in the range of 290–330 m2/g and microporous structures with certain contribution of mesopores in the total porosity. Equilibrium adsorption studies revealed the potential applicability of the materials in water remediation from hazardous organic substances modelled with methylene blue (MB) dye. Generally, this study illustrates the effective conversion of sustainable waste into a functional carbon material. [ABSTRACT FROM AUTHOR]

Particle therapy is a developing area of radiotherapy, mostly involving the use of protons, neutrons and carbon ions for cancer treatment. The reduction of side effects on healthy tissues in the peritumoral area is an important advantage of particle therapy. In this review, we analyze state-of-the-art particle therapy, as compared to conventional photon therapy, to identify clinical benefits and specify the mechanisms of action on tumor cells. Systematization of published data on particle therapy confirms its successful application in a wide range of cancers and reveals a variety of biological effects which manifest at the molecular level and produce the particle therapy-specific molecular signatures. Given the rapid progress in the field, the use of particle therapy holds great promise for the near future. [ABSTRACT FROM AUTHOR]

Oxygen reduction reaction (ORR) is the key reaction for the development of clean and sustainable fuel cells. However, the ORR reaction is sluggish kinetics, thereby it remains a grand challenge to develop high-activity, low-cost, and long-durability electrocatalysts to facilitate the ORR process for practical application. The introduction of dopants into/on the carbon skeleton is known as an efficient route to obtain a novel metal-free electrocatalyst for ORR. Tremendous studies have been performed on the synthesis, structural characterization, catalytic performance and mechanism of the doped carbons as electrocatalysts for ORR in the last decade. In this review, progress in doping engineering on carbons including the types of doping (heteroatom doping, charge-transfer doping, and defective doping) and configurations of heteroatom-doped carbons with corresponding catalytic mechanism will be mainly focused. And the challenges and perspectives on the future development of metal-free doped carbons as electrocatalysts for ORR are given.

Sodium-ion batteries (SIBs) are promising alternatives to replace lithium-ion batteries as future energy storage batteries because of their abundant sodium resources, low cost, and high charging efficiency. In order to match the high energy capacity and density, designing an atomically doped carbonous material as the anode is presently one of the important strategies to commercialize SIBs. In this work, we report the preparation of high-performance dual-atom-doped carbon (C) materials using low-cost corn starch and thiourea (CH4N2S) as the precursors. The electronegativity and radii of the doped atoms and C are different, which can vary the embedding properties of sodium ions (Na+) into/on C. As sulfur (S) can effectively expand the layer spacing, it provides more channels for embedding and de-embedding Na+. The synergistic effect of N and S co-doping can remarkably boost the performance of SIBs. The capacity is preserved at 400 mAh g −1 after 200 cycles at 500 mA g−1; more notably, the initial Coulombic efficiency is 81%. Even at a high rate of high current of 10 A g−1, the cell capacity can still reach 170 mAh g−1. More importantly, after 3000 cycles at 1 A g−1, the capacity decay is less than 0.003% per cycle, which demonstrates its excellent electrochemical performance. These results indicate that high-performance carbon materials can be prepared using low-cost corn starch and thiourea.

Predicting adsorption on nanoporous carbonaceous materials is important for developing various adsorption and membrane separations, as well as for oil and gas recovery from shale reservoirs. Here, we explore the capabilities of 3D molecular models of disordered carbon structures to reproduce the morphological and adsorption features of practical adsorbents. Using grand canonical Monte Carlo simulations, we construct a series of adsorption isotherms of simple fluids (N 2 , Ar, CO 2 , and SO 2) and a series of alkanes from methane to hexane on two model 3D structures, purely microporous structure A and micro-mesoporous structure B. We show that structure A reproduces the morphological properties of commercial Norit R1 Extra activated carbon and demonstrates outstanding agreement between the simulated and experimental adsorption isotherms reported in the literature for all adsorbates considered. Good agreement is also found for simulated and measured isosteric heats. Taking into account inherent variability of structural properties of commercial carbons and experimental adsorption data from different literature sources, the correlations with experiments are truly amazing. This work provides a new insight into the specifics of structural and adsorption properties of nanoporous carbons and demonstrates the advantages of using 3D molecular models for predicting adsorption hydrocarbons and other chemicals by MC simulations. [Display omitted] • 3D molecular models replicate morphological specifics of nanoporous carbons characterized by geometric and adsorption methods. • Monte Carlo generated isotherms of adsorption of simple fluids and hydrocarbons are in good agreement with experimental data on Norit R1 Extra. • Monte Carlo simulations on 3D models reveal the mechanisms of gas adsorption on micro-mesoporous carbons not seen with standard adsorption models. [ABSTRACT FROM AUTHOR]

Carbon materials have shown great promise as cost‐effective electrocatalysts for H2O2 electrochemical production. In this work, we prepare a series of well‐defined pyridinium‐conjugated graphite sheets via nucleophilic substitution reaction of graphite with pyridine derivatives in anodic oxidation process. A combination of experimental and computational investigations confirm that the pyridine derivatives are electrochemically grafted onto the armchair‐type edges of graphitic layers, where the adjacent carbon atoms show the positively charged state by the intramolecular charge transfer. The strong charge delocalization on pyridinium‐conjugated graphite sheets leads to the enhanced electrocatalytic performance for oxygen reduction in terms of both activity and selectivity (above 97 %) for H2O2 production. Moreover, we find that the yield of H2O2 is also affected by the H2O2 decomposing capabilities of functional groups on pyridinium. As one kind of pyrolysis‐free strategies, the proposed electrochemical grafting can serve as a molecularly precise regulation to develop nitrogen doped carbon materials for more applications. [ABSTRACT FROM AUTHOR]

For various adsorbents, especially nanoporous, there is an applicability problem of the Brunauer-Emmett-Teller (BET) method using nitrogen as a probe adsorbate. Therefore, the nitrogen adsorption (a(p/p0)) isotherms in several pressure ranges of the BET method at p/p0 = 0.05–0.3, 0.06–0.22, and narrower are analyzed for a large set (about 200 samples) of essentially different adsorbents such as fumed oxides (individual, binary and ternary, initial and modified), porous silicas, activated carbons and porous polymers. Graphitized carbon black ENVI–Carb composed of nonporous nanoparticles aggregated into microparticles is used as a standard adsorbent characterized by the standard area occupied by nitrogen molecule σm(N2) = 0.162 nm². For initial nanooxides composed of nonporous nanoparticles, the standard value of σm = 0.162 nm2 results in the overestimation of the SBET values by ca. 10 % because of nonparallel-to-surface orientation of slightly polarized N2 molecules interacting with polar surface functionalities (e.g., various hydroxyls). For nanooxides modified by low- and high-molecular (linear, 2D and 3D polymers and proteins) compounds, the overestimation of SBET at σm = 0.162 nm² could reach 30 %, as well as for some activated carbons. For adsorbents possessing nanopores (at half-width x or radius R < 1 nm) and narrow mesopores (1 nm < R < 3 nm), an overlap of monolayer and multilayer sorption (giving apparent underestimation of SBET at σm = 0.162 nm²) and non-parallel-to-surface orientation of the N2 molecules (causing σm lower than 0.162 nm²) could lead to various location of the normalized nitrogen adsorption isotherms (in the BET range) with respect to that for ENVI–Carb. It could be characterized by positive or negative values of the BET constant cBET. Two main criteria showing the inapplicability or applicability of the BET method (with nitrogen as a probe) related to the cBET values and a course of reduced adsorption a×(1- p/p0) vs. p/p0 in the BET range could not be in agreement for adsorbents, which are not pure nanoporous, but they are in agreement for pure nanoporous or meso/macroporous adsorbents. [ABSTRACT FROM AUTHOR]

Most of the biomass‐derived carbon‐based supercapacitors using organic electrolytes exhibit very low energy density due to their low operating potential range between 2.7 and 3.0 V. A novel insight into the concept of the different porous architecture of electrode materials that is employed to extend a device's operating potential up to 3.4 V using TEABF4 in acetonitrile, is reported. The combination of two high surface area activated carbons derived from abundant natural resources such as industrial waste cotton and wheat flour as sustainable and green carbon precursors is explored as an economical and efficient supercapacitor carbon electrode. Benefitting from the simultaneous achievement of the higher potential window (3.4 V) with higher volumetric capacitance (101 F cm–3), the supercapacitor electrodes exhibit higher volumetric energy density (42.85 Wh L–1). Bimodal pore size distribution of carbon with a tuned pore size and high specific surface area of the electrode can promote the fast transport of cations and anions. Hence, it exhibits a high rate capability even at 30 A g–1. In addition, the electrodes remain stable during operation cell voltage at 3.4 V upon 15 000 charging–discharging cycles with 90% capacitance retention. [ABSTRACT FROM AUTHOR]

The CO2 capture using adsorption can reduce the carbon footprint, increasing the sustainability of the process without the production of wastes present in commonly used industrial operations. The present research work analyses the effect of the doping-agents incorporation in carbon materials upon adsorption and separation of gases, specifically for carbon dioxide and nitrogen. The carbons precursor was polyacrylonitrile (PAN), which enabled the incorporation of nitrogen atoms in the structure, whereas sulphur doping was reached using pure sulphur after the carbonisation step. The influence of several variables (such as temperature or pressure) and characteristics of synthesised materials (mainly corresponding to surface characteristics) on carbon dioxide separation has been evaluated. Adsorption isotherms were determined for each gas (CO2 and N2) at different temperatures and pressures. Different adsorption models were evaluated to fit the experimental data. In general, the Toth isotherm described better the adsorption for both gases. Important parameters such as CO2/N2 selectivity and heat of adsorption were determined using the IAS theory and the experimental isotherms at different temperatures, respectively. Non-activated carbons generated from PAN carbonisation without sulphur addition showed the highest values of selectivity (up to 400) and adsorption heat (up to 40 kJ mol−1), mainly at low pressures and at low carbon dioxide uptakes, respectively. Furthermore, thanks to their high adsorption capacity, these carbons can be applied for carbon dioxide separation from mixtures with nitrogen. [ABSTRACT FROM AUTHOR]

Abstract Most of the biomass‐derived carbon‐based supercapacitors using organic electrolytes exhibit very low energy density due to their low operating potential range between 2.7 and 3.0 V. A novel insight into the concept of the different porous architecture of electrode materials that is employed to extend a device's operating potential up to 3.4 V using TEABF4 in acetonitrile, is reported. The combination of two high surface area activated carbons derived from abundant natural resources such as industrial waste cotton and wheat flour as sustainable and green carbon precursors is explored as an economical and efficient supercapacitor carbon electrode. Benefitting from the simultaneous achievement of the higher potential window (3.4 V) with higher volumetric capacitance (101 F cm–3), the supercapacitor electrodes exhibit higher volumetric energy density (42.85 Wh L–1). Bimodal pore size distribution of carbon with a tuned pore size and high specific surface area of the electrode can promote the fast transport of cations and anions. Hence, it exhibits a high rate capability even at 30 A g–1. In addition, the electrodes remain stable during operation cell voltage at 3.4 V upon 15 000 charging–discharging cycles with 90% capacitance retention.

Abstract The quest for more efficient ways to store electrical energy prompted the development of different storage devices over the last decades. This includes but is not limited to different battery concepts and supercapacitors. However, modern batteries rely on electrochemical principles that often involve transition metals which can for instance suffer from toxicity or limited availability. More sustainable alternatives are needed. This sparked the search for organic electrode materials. Nevertheless, compared to their inorganic counterparts, organic electrode materials remain less intensely investigated. Besides the often more complicated electrochemical principles, one likely reason for that are the complex synthetic skills required to develop novel organic materials. Here we review materials synthesized by an old and comparably simple reaction from the field of organic chemistry, namely Schiff‐base formation. This reaction can often yield materials under relatively mild conditions, making them especially interesting for the formation of sustainable electrodes. The main weakness of Schiff‐base materials, susceptibility to hydrolysis, is of limited concern in most of the battery systems as they mostly anyways require water‐free conditions. This review gives an overview of some selected nanomaterials obtained from Schiff‐base formation as well as their carbonized derivatives which are of interest for energy storage. Firstly, the general chemistry of Schiff‐bases is introduced, followed by an in‐depth survey of the most important breakthroughs in the formation of organic battery electrodes that involve materials based on Schiff‐base reaction. Lastly, an outlook considering the main hurdles as well as future perspectives of this research area is given.

Particle therapy is a developing area of radiotherapy, mostly involving the use of protons, neutrons and carbon ions for cancer treatment. The reduction of side effects on healthy tissues in the peritumoral area is an important advantage of particle therapy. In this review, we analyze state-of-the-art particle therapy, as compared to conventional photon therapy, to identify clinical benefits and specify the mechanisms of action on tumor cells. Systematization of published data on particle therapy confirms its successful application in a wide range of cancers and reveals a variety of biological effects which manifest at the molecular level and produce the particle therapy-specific molecular signatures. Given the rapid progress in the field, the use of particle therapy holds great promise for the near future.

• The mechanism of ORR on FeN 4 -doped carbon nanotubes and graphene is studied. • As a support, single-walled (6,6)-armchair and (12,0)-zigzag nanotubes were chosen. • C 2 site becomes catalytically active on the metal CO-poisoned catalysts. • The effect of the support and relative orientation of the FeN 4 motif is discussed. Theoretical calculations at the revPBE0-D3(PCM)/def2-TZVP level were performed to investigate the mechanism of the oxygen reduction reaction (ORR) on the FeN 4 -doped NCMs (graphene, single-walled (6,6)-armchair and (12,0)-zigzag carbon nanotubes) as catalysts. The effect of the support and relative orientation of FeN 4 fragment in the catalyst structure on the ORR activity and stability of the differently adsorbed successive intermediates (O 2 *, HO 2 *, O*, HO*, H 2 O 2 *, H 2 O*) is discussed. Special attention is given to the possible poisoning effect of CO. The relative catalytic activity of the metal center and the adjacent C 2 site of the carbon support are analyzed depending on the structure of the support. The metal catalytic center on the armchair nanotube and graphene supports is prone to deactivation by poisoning with CO, whereas in the zigzag nanotube supported catalyst the metal center is tolerant to CO. The four-electron mechanism of ORR is shown to be preferable over the two-electron mechanism in both acidic and alkaline media, both on the metal and C 2 centers. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • By tunning preparation conditions of porous carbons, efficient textural features and CO 2 uptakes were achieved. • CM1-900-2 sample exhibit ultra-high specific surface area (3019 m2 g−1) and large micropore volume (1.13 cm3 g−1). • Excellent CO 2 adsorption capacity with value 297. 05 mg g−1 (6.75 mmol g−1) at 273 K and 1 bar were recorded. In this work, we developed a simple methodology for producing highly porous carbons. Herein, we combined the hydrothermal method with chemical activation to fabricate cellulose-based, melamine modified porous carbons, using acetic acid as an additive. The preparation conditions including activation temperature, activation time, and melamine ratio were varied to obtain an optimized adsorbent exhibiting efficient textural features and maximized carbon dioxide (CO 2) adsorption uptake. By varying the preparation conditions, high specific surface area (SSA) (1260–3019 m2 g−1), microporosity in the range of 0.21–1.13 cm3 g−1, and a well-developed porous structure was obtained. The optimized adsorbent exhibits an excellent CO 2 adsorption uptake of 297.05 mg g−1 (6.75 mmol g−1) and 174.4 mg g−1 (3.96 mmol g−1) at 273 K and 298 K at 1 bar, respectively, due to the existence of ultra-micropores (<0.68 nm, < 0.81 nm), high SSA (3019 m2 g−1), and high nitrogen content (8%). Furthermore, the role of micropores in the CO 2 adsorption process suggests that micropores between 0.68 nm and 1 nm exhibit high CO 2 adsorption potential. Additionally, all synthesized carbons exhibited a high isosteric heat of adsorption (45 kJ mol−1) and a greater affinity for adsorbed CO 2 species than nitrogen (N 2) molecules. Thus, as-fabricated porous carbon adsorbents are an effective competitor for CO 2 uptake applications to mitigate global warming. [ABSTRACT FROM AUTHOR]

Pore structure characterization plays a crucial role in the optimization of adsorption properties of nanoporous carbons employed for water purification, gas and liquid phase separations, carbon dioxide reduction, energy storage, and other applications. Here, we present an original methodology for evaluating the pore size distribution in carbons in a wide range of micro- and mesopores from 0.385 to 10 nm from a single isotherm of high-pressure adsorption of CO 2 at 273 K. The proposed method is based on the reference theoretical isotherms calculated by Monte Carlo simulations in model pores of slit-shaped and cylindrical geometry. The relationship between the pore size and the pore filling pressure is established. Special attention is given to the predicting of the capillary condensation transitions in mesopores by using the meso-canonical ensemble (gauge cell) Monte Carlo simulations. The proposed technique is demonstrated and verified against the conventional N 2 and Ar low temperature adsorption methods drawing on the example of micro-mesoporous carbons of the CMK family. Advantages and limitations of CO 2 adsorption characterization of nanoporous materials are discussed and further improvements are proposed. Image 1 [ABSTRACT FROM AUTHOR]

Medicinal and aromatic plants have been used by mankind since ancient times. This is primarily due to their healing effects associated with their specific secondary metabolites (some of which are also used as drugs in modern medicine), or their structures, served as a basis for the development of new effective synthetic drugs. One way to increase the production of these secondary metabolites is to use nanoparticles that act as elicitors. However, depending on the specific particle size, composition, concentration, and route of application, nanoparticles may have several other benefits on medicinal and aromatic plants (e.g., increased plant growth, improved photosynthesis, and overall performance). On the other hand, particularly at applications of high concentrations, they are able to damage plants mechanically, adversely affect morphological and biochemical characteristics of plants, and show cytotoxic and genotoxic effects. This paper provides a comprehensive overview of the beneficial and adverse effects of metal-, metalloid-, and carbon-based nanoparticles on the germination, growth, and biochemical characteristics of a wide range of medicinal and aromatic plants, including the corresponding mechanisms of action. The positive impact of nanopriming and application of nanosized fertilizers on medicinal and aromatic plants is emphasized. Special attention is paid to the effects of various nanoparticles on the production of valuable secondary metabolites in these plants cultivated in hydroponic systems, soil, hairy root, or in vitro cultures. The beneficial impact of nanoparticles on the alleviation of abiotic stresses in medicinal and aromatic plants is also discussed. [ABSTRACT FROM AUTHOR]

In this report, we demonstrate that high-capacity hybrid supercapacitors can be realized by utilizing iron azaphthalocyanine (FeAzPc-4N) adsorbed activated carbons (ACs) as an electrode due to the combination of the electric double layer of activated carbon surfaces and redox reactions of FeAzPc-4N molecules. By increasing the mixing ratio of FeAzPc-4N with ACs, a maximum capacity of 907 F/g AC is achieved, also enabling rapid charging and discharging at 20 A/g. The revelation of the capacitor electrode's durability through 20 000 cycles of charging and discharging is realized, and the capacitor cell had sufficient output power to illuminate LEDs. This concept illustrates the potential for enhancing capacitor performance by immobilizing redox-active species.

We reported the fabrication of an electrochemical sensor for uric acid (UA) monitoring using metal-free electrode based on heteroatoms (S, N, P, and O) doped carbon (HADC) nanoparticles, derived from polyphosphazene, synthesized via precipitation polymerization reaction between hexachlorocyclotriphosphazene (HCCP) and 1,4-dithiane-2,5-diol (DD) under sonication irradiations at 40 °C, following its modification with benzimidazolium-1-acetate ionic liquid (BIL). The developed HADC-BIL electrode showed a highly sensitive and selective response toward UA even in the presence of highly electroactive interferences such as ascorbic acid (AA), dopamine (DA), glucose (Glu), and hydrogen peroxide (H2O2). Our results demonstrated that the as-fabricated HADC-BIL electrode allows us to detect UA over a linear range of 2–1050 μM with a detection limit of 1.27 μM. Further, we were able to monitor the amount of UA level in the blood of a gout patient using the developed HADC-BIL electrode, which ensures the effectiveness of the developed sensor for the sensitive and selective detection of UA from real samples. [ABSTRACT FROM AUTHOR]

Ozone is a strong oxidizer and sulfur dioxide is a precursor to acid rain, both are air pollutants that can damage the respiratory tissues of animals and plants making them hazardous to the environment. They are isoelectronic valence O = X = O (X = S, O) molecules and their mechanism of reduction on carbons is similar. The solid–gas kinetics were studied in a flow system with a tubular reactor under differential and steady state conditions. Initial rates and product distribution were used to determine the stoichiometry of the reaction. The reduction of XO2 on carbons proceeds through a common primary mechanism with oxidized and reduced intermediates. The reactivity of the intermediates that were inserted on carbons (graphite, activated carbon, graphene oxide) modified by SO2 is selective with respect to aminolysis and thiolysis. A theoretical study of the chemisorption of SO2 on dehydrogenated pyrene as graphite active site model showed that at 900 °C the chemisorption occurs mainly on the diradical zigzag edge. Computational quantum chemistry calculations were carried out for the reduction of SO2 on graphite to produce elemental sulfur and CO2 using tetradehydrogenated-benzo[α]anthracene (TBA) as model. The mechanisms of the decarboxylation and sulfur transport steps were postulated. Ozonation of graphite showed that the 1,2,3-trioxolane decomposes to an oxyrene, eliminating O2. Both reactions, the SO2 and O3 with graphite, have the same experimental free energy of activation for the decarboxylation reaction. The results show that for SO2 the desulfurization has a much lower energetic demand than the decarboxylation route raising the important possibility of using the reaction of reduction of SO2 on carbons to reduce the acid rain, producing elemental sulfur as the main product, without increasing the greenhouse effect due to the formation of CO2. [ABSTRACT FROM AUTHOR]

Background: The excess sludge produced by sewage treatment plants contains a large number of pollutants, which is of huge environmental risk. Transforming this kind of solid waste into adsorption materials is an effective approach to realize the resource utilization of sludge. Combined with hydrothermal pretreatment and chemical activation, the synthesis of sludge‐based mesoporous carbon is used to remove bisphenol A (BPA) in wastewater. Results: A resource recycling measure to prepare mesoporous activated carbons (MACs) from sewage sludge was developed via the combination of hydrothermal pretreatment and chemical activation using sewage sludge and sulfuric acid as carbon precursor and activating agent, respectively. The combination of hydrothermal pretreatment and chemical activation not only can make efficient use of the activating agents but also facilitate the deep pyrolysis of the sludge. The resultant MAC obtained using the hydrothermal pretreatment possessed a larger total surface area, less crystalline phase and a narrower pore size distribution compared to other samples. Meanwhile, the MAC obtained from hydrothermal pretreatment presented the highest amount of adsorption of BPA and achieved a better capture than the reference commercial activated carbons. In addition, a possible adsorption mechanism has been proposed to further analyze the enhanced adsorption performance. Conclusions: The yield and mesoporous content of the obtained MAC is 59.19% and 31.51%, respectively. The maximum adsorption capacity for BPA is 137.87 mg g−1. Microporosity, hydrogen bonding and π–π effect introduced by the hydrothermal pretreatment play an important role in BPA adsorption. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Water and benzene were compared as probe liquids for thermoporometric characterization of mesoporous carbons. For testing, four different carbonaceous materials were prepared by soft- or hard-templating procedures with mesopore diameters in the range 3–12 nm. In addition, all materials were tested in hydrophobic (pristine, carbonized at 900 °C) and hydrophilic (moderate oxidation by persulphate) form. The results show that both tested liquids express a good linear correlation between heat of melting in pores (measured as DSC peak area) and volume of mesopores. Melting point depression of probe liquid confined in pores related to mesopore size was found out to be steeper for benzene confirming a higher value of Gibbs-Thomson constant of benzene compared to water. Neither heat of melting in pores nor melting point depression were affected by carbon surface oxidation. Contrary, the non-freezing layer (δ layer) of a liquid in pores was considerably wider for most of hydrophilic samples than hydrophobic ones when water was employed, while it stayed nearly constant when benzene was applied. Nevertheless, both tested probe liquids generally enable to obtain similar pore size distributions if appropriate values of δ layers are used. Benzene as a probe liquid in thermoporometry of carbons have some advantages compared to water but only in limited cases. Benzene can be recommended for characterisation of large mesopores and its usage can be beneficial for comparison of analogous samples with different surface chemistry. [Display omitted] • Benzene recommended for characterisation of samples with large mesopores. • Wider δ layer for most of oxidized than non-oxidized carbons using water. • Almost constant δ layer for most of oxidized and non-oxidized carbons using benzene. • Benzene recommended for characterisation of samples differing in surface chemistry. • Similar pore size distributions for water and benzene using appropriate δ layers. [ABSTRACT FROM AUTHOR]

This work aims to study the adsorption of a trace element (in our case we selected Cobalt (II)), on silicas and mesoporous coals of CMK-3 and CMK-3C type. These were made based on the synthesis of SBA-15 and CMI-1 as molds. Characterization of these materials was performed by X-ray diffraction, SEM and nitrogen adsorption-desorption (BET). The adsorptional properties of these materials were evaluated by studying the kinetics and adsorption isotherms of cobalt (II) metal ions. The Cobalt (II) adsorption experiments on the four matrices showed globally that the adsorption efficiencies of cobalt can be classified according to the order: CMK-3 > CMK-3C > CMI-1 > SBA-15, with efficiencies of 94.54%, 88.41% 76.09%, 74.07% respectively. Results of the cobalt adsorption kinetics modeling by the four materials in aqueous medium under optimal operating conditions is pseudo first order with adjustment coefficients (R²> 0.98). The adsorption isotherms clearly show that the Freundlich model is the most suitable for the different adsorption isotherms with adjustment coefficients (R²> 0.97). [ABSTRACT FROM AUTHOR]

Abstract In this study, new rGO-silica xerogel nanocomposites (SX-rGO) and its glass fiber reinforced composites (GFR-SX-rGO) were prepared, and its microstructure and thermal properties were evaluated. The raw material was a mixed dispersion prepared by adding 0.01–2.5 wt% of reduced graphene oxide (rGO) to waterglass (6% SiO 2). A hydrogel was prepared via sol-gel reaction of this raw material, which was then immersed in hydrochloric acid, hydrophobized in a siloxane/2-propanol reaction system, and then dried at ambient pressure to obtain a hydrophobic carbon-silica xerogel composite. The obtained samples were characterized by N 2 physisorption (at 77 K), solid 29Si Magic angle spinning nuclear magnetic resonance spectroscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy, differential scanning calorimetry, thermogravimetric analysis, hydrophobicity, and thermal conductivity. It was found that as the amount of rGO was increased, the specific surface area of the nanocomposite decreased by ~25% from 535 to 403 cm2/g, and the average pore size and pore volume were almost halved. The thermal decomposition temperature of the SX-rGO was increased markedly by the addition of rGO. Moreover, the GFR-SX-rGO-0.5 showed low density (0.208 g/cm3), high contact angle (146°) and low thermal conductivity (0.0199 W/mK). [ABSTRACT FROM AUTHOR]

Medicinal and aromatic plants have been used by mankind since ancient times. This is primarily due to their healing effects associated with their specific secondary metabolites (some of which are also used as drugs in modern medicine), or their structures, served as a basis for the development of new effective synthetic drugs. One way to increase the production of these secondary metabolites is to use nanoparticles that act as elicitors. However, depending on the specific particle size, composition, concentration, and route of application, nanoparticles may have several other benefits on medicinal and aromatic plants (e.g., increased plant growth, improved photosynthesis, and overall performance). On the other hand, particularly at applications of high concentrations, they are able to damage plants mechanically, adversely affect morphological and biochemical characteristics of plants, and show cytotoxic and genotoxic effects. This paper provides a comprehensive overview of the beneficial and adverse effects of metal-, metalloid-, and carbon-based nanoparticles on the germination, growth, and biochemical characteristics of a wide range of medicinal and aromatic plants, including the corresponding mechanisms of action. The positive impact of nanopriming and application of nanosized fertilizers on medicinal and aromatic plants is emphasized. Special attention is paid to the effects of various nanoparticles on the production of valuable secondary metabolites in these plants cultivated in hydroponic systems, soil, hairy root, or in vitro cultures. The beneficial impact of nanoparticles on the alleviation of abiotic stresses in medicinal and aromatic plants is also discussed.

• Porous carbons are sought for VOC removal but lose efficiency in humid conditions. • This study employs interparticle hydrogen spillover to modify carbon for adsorption in humid conditions. • Spillover hydrogen facilitates the reduction of O-C = O groups into phenolic species. • Such conversion plays a crucial role in preserving dynamic benzene uptake under humid conditions. • This method offers new avenues for creating efficient carbon adsorbents for VOCs in air. Porous carbons have attracted much attention as adsorbents for the removal of volatile organic compounds (VOCs), but they suffer from a significant loss in adsorption capacity when exposed to humid conditions. In this study, zeolite templated carbons (ZTCs) are post-treated with O 2 , H 2 , and spillover hydrogen. This process generates varying amounts and types of oxygen-containing functional groups (OFGs) at the carbon surface while maintaining the initial textural properties. Results from Boehm titration and FT-IR reveal that spillover hydrogen not only removes the OFGs in carbon more effectively, but also facilitates the reduction of O–C = O groups (i.e., Lactonic and Carboxyl groups) into Phenolic species. The dynamic adsorption behavior of the series of post-treated ZTCs for benzene is investigated under both dry and humid conditions (relative humidity = 80 %). The results indicate that ZTC treated with spillover hydrogen exhibits noticeable resistance to H 2 O poisoning in benzene adsorption, while the other three ZTC show similar behaviors. Furthermore, there is a scaling relationship between the fractions of Phenolic groups among OFGs and benzene uptake under humid conditions. It is believed that the types of OFGs on carbon surfaces are a critical consideration when designing VOC adsorbents for their use under humid conditions. [ABSTRACT FROM AUTHOR]