Polluted water resources, particularly those polluted with industrial effluents' dyes, are carcinogenic and hence pose a severe threat to sustainable and longstanding worldwide development. ...Meanwhile, adsorption is a promising process for polluted/wastewater treatment. In particular, activated carbon (AC) is popular among various wastewater treatment adsorbents, especially in the organic contaminants' remediation in wastewater. Hence, the AC's synthesis from degradable and non-degradable resources, the carbon activation involved in the AC synthesis, and the AC's modification to cutting-edge and effective materials have been modern-research targets in recent years. Likewise, the main research focuses worldwide have been the salient AC characteristics, such as its surface chemistry, porosity, and enhanced surface area. Notably, various modified-AC synthesis methods have been employed to enhance the AC's potential for improved contaminants-removal. Hence, we critically analyze the different modified ACs (with enhanced (surface) functional groups and textural properties) of their capacity to remove different-natured anionic dyes in wastewater. We also discuss the corresponding AC modification techniques, the factors affecting the AC properties, and the modifying agents' influence on the AC's morphological/adsorptive properties. Finally, the AC research of future interest has been proposed by identifying the current AC research gaps, especially related to the AC's application in wastewater treatment.
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•Dye-polluted wastewater is carcinogenic.•AC-based adsorption is a promising process for dye-polluted wastewater treatment.•AC's surface chemistry, porosity, and enhanced surface area are reviewed in detail.•AC modification techniques, tuning factors, and the modifying agents' are reviewed.•Research gaps in the application of AC in wastewater treatment are furnished.
Abstract
Recent advances in nanomaterials and nano-microfabrication have enabled the development of flexible wearable electronics. However, existing manufacturing methods still rely on a multi-step, ...error-prone complex process that requires a costly cleanroom facility. Here, we report a new class of additive nanomanufacturing of functional materials that enables a wireless, multilayered, seamlessly interconnected, and flexible hybrid electronic system. All-printed electronics, incorporating machine learning, offers multi-class and versatile human-machine interfaces. One of the key technological advancements is the use of a functionalized conductive graphene with enhanced biocompatibility, anti-oxidation, and solderability, which allows a wireless flexible circuit. The high-aspect ratio graphene offers gel-free, high-fidelity recording of muscle activities. The performance of the printed electronics is demonstrated by using real-time control of external systems via electromyograms. Anatomical study with deep learning-embedded electrophysiology mapping allows for an optimal selection of three channels to capture all finger motions with an accuracy of about 99% for seven classes.
Recent progress in electronic skin or e‐skin research is broadly reviewed, focusing on technologies needed in three main applications: skin‐attachable electronics, robotics, and prosthetics. First, ...since e‐skin will be exposed to prolonged stresses of various kinds and needs to be conformally adhered to irregularly shaped surfaces, materials with intrinsic stretchability and self‐healing properties are of great importance. Second, tactile sensing capability such as the detection of pressure, strain, slip, force vector, and temperature are important for health monitoring in skin attachable devices, and to enable object manipulation and detection of surrounding environment for robotics and prosthetics. For skin attachable devices, chemical and electrophysiological sensing and wireless signal communication are of high significance to fully gauge the state of health of users and to ensure user comfort. For robotics and prosthetics, large‐area integration on 3D surfaces in a facile and scalable manner is critical. Furthermore, new signal processing strategies using neuromorphic devices are needed to efficiently process tactile information in a parallel and low power manner. For prosthetics, neural interfacing electrodes are of high importance. These topics are discussed, focusing on progress, current challenges, and future prospects.
Recent progress in electronic skin research is broadly reviewed, focusing on the technologies required in the following three applications: skin‐attachable electronics, robotics, and prosthetics. Topics such as stretchability, self‐healing, biocompatibility, tactile sensing, chemical and electrophysiological sensing, wireless communication, large‐area integration, neuromorphic signal processing, and neural interfaces are discussed.
Renewable and sustainable energy production is essential for future technological requirements, owing to the ever-increasing environmental pollution caused by the use of non-renewable fossil fuels. ...The conversion of abundant solar energy to solar fuels by photocatalysis has been suggested as an adequate and alternative route to address the aforementioned issue. A wide range of catalysts have been studied, but their low photocatalytic efficiency due to rapid electron-hole recombination (e.g., C3N4) and high cost (e.g., Pt) have limited their commercialization. There is an urgent need to develop economically/eco-friendly, highly efficient, and robust catalysts for enhanced photocatalysis to tackle the energy crisis and environmental issues. Semiconductor-based catalysts are commonly used as excellent compound materials for photocatalytic reaction applications because of their tunable energy band edge potential, abundance, and less poisonous characteristics. On the other hand, these have limitations due to charge recombination, poor stability, and low conductivity. The current review emphasizes the recent progress on semiconducting materials integrated with carbon (biochar) materials, which are a good choice to minimize these issues. This review summarizes the progress of recent research works for the development of highly active biochar-based composite systems to promote further developments of biochar-modified semiconductors in photocatalytic applications. Biochar has played a pivotal role in photocatalysis because of its fascinating benefits, such as a good support material, enhanced the specific surface area, and numerous surface active sites. These properties have led to high charge shuttling and acting as an electron reservoir, promoting greater charge separation and reducing the energy bandgap. The typical applications of biochar-modified photocatalytic materials are reviewed mainly in photocatalytic hydrogen production and other energy and environmental areas, such as carbon dioxide photo-reduction and the abatement of polluted water/air treatment under solar light irradiation. This review focuses on the recent trends and future prospects for the development of ecofriendly biochar-modified semiconductor photocatalysts.
This review highlighted the synthesis of biochar and biochar modified catalysts, which includes various modification techniques for energy and environmental applications of photocatalytic water splitting, CO2 photoreduction and abatement of water/air pollutants. Display omitted
•Different synthesis methods of biochar (BC) and BC based catalysts.•Various activation and functionalization strategies of BC.•Clarify the role of BC based catalysts in photocatalysis.•Offer a new perspective to use BC based catalyst in energy and environmental fields.
The epigenomic reader Brd4 is an important drug target for cancers. However, its role in cell differentiation and animal development remains largely unclear. Using two conditional knockout mouse ...strains and derived cells, we demonstrate that Brd4 controls cell identity gene induction and is essential for adipogenesis and myogenesis. Brd4 co-localizes with lineage-determining transcription factors (LDTFs) on active enhancers during differentiation. LDTFs coordinate with H3K4 mono-methyltransferases MLL3/MLL4 (KMT2C/KMT2D) and H3K27 acetyltransferases CBP/p300 to recruit Brd4 to enhancers activated during differentiation. Brd4 deletion prevents the enrichment of Mediator and RNA polymerase II transcription machinery, but not that of LDTFs, MLL3/MLL4-mediated H3K4me1, and CBP/p300-mediated H3K27ac, on enhancers. Consequently, Brd4 deletion prevents enhancer RNA production, cell identity gene induction and cell differentiation. Interestingly, Brd4 is dispensable for maintaining cell identity genes in differentiated cells. These findings identify Brd4 as an enhancer epigenomic reader that links active enhancers with cell identity gene induction in differentiation.
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•Recent discoveries in solvent liquefaction of lignocellulose are introduced.•Biofuels, antioxidant, bio-polyols, and chemicals were produced from lignocellulose.•A plausible ...degradation pathway of each biomass component is suggested.•The challenges and future perspective of solvent liquefaction process is discussed.
The concerns over the increasing energy demand and cost as well as environmental problems derived from fossil fuel use are the main driving forces of research into renewable energy. Lignocellulosic biomass comprised of cellulose, hemicellulose, and lignin is an abundant, carbon neutral, and alternative resource for replacing fossil fuels in the future. Solvent liquefaction of lignocellulosic biomass is a promising route to obtain biofuels, bio-based materials, and chemicals using a range of solvents as reaction media under moderate reaction conditions. Recently, several researchers have considered novel approaches for enhancing the process efficiency and economics.
This review article reports the state-of-the-art knowledge of lignocellulose liquefaction in the recent three years with the main focus on the feedstock, liquefaction technology, target products, and degradation mechanism of each biomass component. This review is expected to provide an important reference for research into the solvent liquefaction of lignocellulose in the near future.
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•Strategic use of biochar for CO2 capture and storage (CCS).•Porosity of biochar proves a significant determinant for CCS.•Economic viability of biochar is superior in reference to ...other CCS materials.•Carbon negativity of biochar maximizes the effect of CCS.
Dramatic increase of CO2 emissions to sate the global carbon demand for chemicals, goods, and fuels has been regarded as one of the main contributors triggering global warming. Note that CO2 emissions are over the Earth’s full capacity to assimilate carbons via the natural carbon cycle. In these respects, CO2 capture and sequestration have been considered as one of the strategic principles to cancel out CO2 release from the anthropogenic activities in line with the use of fossil fuels. Thus, it is desirable to develop the efficient CO2 sorptive materials that are economically viable. Among CO2 sorptive materials, biochar (i.e., porous carbon-based materials) has been considered as one of the promising candidates. Indeed, a great deal of researches on biomass has been performed. Based on these rationales, this review laid great emphasis on informing the recent studies of activated biochars for CO2 adsorption, which were fabricated from various biomasses. Also, this review offered the up-to-date knowledge on the physicochemical properties of activated biochars in line with their synthesis procedures. Lastly, the effects of biochar properties on CO2 capture and separation was summarized with in-depth assessment of the activated biochars.
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•Effect of critical parameters of 2D g-C3N4 on CO2 reduction is discussed.•Effective charge separation for high selectivity and activity with 2D g-C3N4 in solar fuels is ...necessary.•Impact of crystal design on 2D g-C3N4, which controls the fate of reaction intermediates, is reviewed.•Strategic approaches to improve photocatalytic CO2 reduction with 2D g-C3N4 are suggested.
Photocatalytic CO2 reduction is the key strategic factor to mitigate the detrimental consequences arising from greenhouse gases (predominantly anthropogenic CO2). Products (CH4, C2H6, CH3OH, C2H5OH, etc.,) that are derived from the reduction of CO2 could be promising alternatives to petro-derived fuel/chemicals. Even though a great deal of efforts has been devoted to increase the conversion efficiency of CO2, the technical readiness level (TRL) has not yet been fully matured. This review emphasizes on the emerging functional material ultrathin two-dimensional (2D) nanosheet graphitic carbon nitride (g-C3N4) for the reduction of CO2 into value-added products. Physico-chemical properties of 2D-cabon nitride (sizeable surface-to-volume ratio, supplementary active sites onto the surface, shorter diffusion length, bandgap tuning, atomic thickness, and bulk to surface charge transportation) governing the photocatalytic activity are discussed. This review provides recent advances in 2D-carbon nitride photocatalysts to highlight the ongoing challenges and new strategies to optimize their functionality for improved selectivity for CO2 conversion.
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•In-situ catalytic hydropyrolysis of lignin using HY catalyst.•Ex-situ catalytic hydrodeoxygenation of lignin-derived phenolics at mild conditions.•Selective conversion of lignin into ...aromatic hydrocarbons.•FeReOx/ZrO2: a potential catalyst for mild HDO of lignin-derived phenolics.
Lignin, with its polyaromatic structure and as a main component of lignocellulosic biomass, is considered as an important renewable source of aromatics which are currently obtained from fossil fuels. Lignin pyrolysis gives a liquid product with a high content of phenolic compounds which can be further upgraded to aromatic hydrocarbons through catalytic approaches. In this work, in-situ catalytic hydropyrolysis combined with a subsequent ex-situ catalytic hydrodeoxygenation step was implemented to achieve an enhanced conversion of kraft lignin into aromatic hydrocarbons. The main point is that the ex-situ catalytic upgrading was conducted at mild conditions (temperature: 350 °C; pressure: 1 atm). HY was used as in-situ catalyst for enhanced decomposition of lignin. Fe/HBeta, FeReOx/MCM-41, Fe/ZrO2 and FeReOx/ZrO2 were used as ex-situ catalyst, among which the oxophilic, mesoporous and mild-acidic catalyst of FeReOx/ZrO2 revealed the highest HDO efficiency. Importantly, FeReOx/MCM-41, Fe/ZrO2 and FeReOx/ZrO2 led to significantly lower yield of coke compared to a zeolite-supported catalyst like Fe/HBeta. This suppression of coke formation is a result of reduced phenolic trapping inside catalyst mainly due to the mesoporosity and moderate acid strength of catalyst.
•Recent advances in catalytic co-pyrolysis are introduced.•Catalytic co-pyrolysis is efficient to upgrade the quality of bio-oil.•Acid catalysts improve deoxygenation and aromatization.•Base ...catalysts facilitate ketonization, aldol condensation, and hydrogen abstraction.•The challenges and future perspective of catalytic co-pyrolysis is discussed.
The global economy is threatened by the depletion of fossil resources and fluctuations in fossil fuel prices, and thus it is necessary to exploit sustainable energy sources. Carbon-neutral fuels including bio-oil obtained from biomass pyrolysis can act as alternatives to fossil fuels. Co-pyrolysis of lignocellulosic biomass and plastic is efficient to upgrade the quality of bio-oil because plastic facilitates deoxygenation. However, catalysts are required to produce bio-oil that is suitable for potential use as transportation fuel. This review presents an overview of recent advances in catalytic co-pyrolysis of biomass and plastic from the perspective of chemistry, catalyst, and feedstock pretreatment. Additionally, this review introduces not only recent research results of acid catalysts for catalytic co-pyrolysis, but also recent approaches that utilize base catalysts. Future research directions are suggested for commercially feasible co-pyrolysis process.
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