High Surface Area Nanoporous Carbon-Ceria Composites for CO2 Capture and Enzyme-Mimicking Action.

Nanoporous carbon-based composites with metal oxides have great potential for various applications including adsorption and sensing owing to their multiple properties. However, the fabrication of these nanocomposites without affecting these multiple properties is challenging. Herein, a series of nanoporous carbon-based nanocomposites with cerium nanoparticles are synthesized through a combination of high-temperature carbonization and ex-situ modification with cerium precursor. The prepared nanocomposites have appreciable surface areas, pore volumes, tunable pore sizes, and a controlled amount of surface nanoceria, all of which can be precisely controlled by varying the amount of KOH and cerium nitrate hexahydrate used for nanoceria generation. The porous carbon PC-3 was used for modification using nanoceria and the modified materials showed higher performance for all three applications. The CO2 adsorption per unit surface of PC-3 (2.4 µmol m-2) increased to 2.9 µmol m-2 in Ce-PC-3-0.5. Furthermore, the composite materials displayed higher heat of adsorption (Qst) than bare materials, indicating stronger interactions with CO2. Interestingly, the least amount of nanoceria (CePC-3-0.25) was effective in enhancing the superoxide dismutase (SOD) and catalase activity.

From cane to nano: advanced nanomaterials derived from sugarcane products with insights into their synthesis and applications.

Sugarcane-based products are inherently rich in elements such as silicon, carbon and nitrogen. As such, these become ideal precursors for utilization in a wide array of application fields. One of the appealing areas is to transform them into nanomaterials of high interest that can be employed in several prominent applications. Among nanomaterials, sugarcane products based on silica nanoparticles (SNPs), carbon dots (CDs), metal/metal oxide-based NPs, nanocellulose, cellulose nanofibers (CNFs), and nano biochar are becoming increasingly reported. Through manipulation of the experimental conditions and choosing suitable starting precursors and elements, it is possible to devise these nanomaterials with highly desired properties suited for specific applications. The current review presents the findings from the recent literature wherein an effort has been made to convey new development in the field of sugarcane-based products for the synthesis of the above-mentioned nanomaterials. Various nanomaterials were systematically discussed in terms of their synthesis and application perspectives. Wherever possible, a comparative analysis was carried out to highlight the potential of sugarcane products for the intended purpose as compared to other biomass-based materials. This review is expected to stand out in delivering an up-to-date survey of the literature and provide readers with necessary directions for future research.

This review focuses on sugarcane-derived nanomaterials such as silica, nano cellulose, nanofibers, nanocrystals and metal/nonmetal nanoparticles and their application in various energy and environmental fields.

Recent Advances in Functionalized Biomass-Derived Porous Carbons and their Composites for Hybrid Ion Capacitors.

Hybrid ion capacitors (HICs) have aroused extreme interest due to their combined characteristics of energy and power densities. The performance of HICs lies hidden in the electrode materials used for the construction of battery and supercapacitor components. The hunt is always on to locate the best material in terms of cost-effectiveness and overall optimized performance characteristics. Functionalized biomass-derived porous carbons (FBPCs) possess exquisite features including easy synthesis, wide availability, high surface area, large pore volume, tunable pore size, surface functional groups, a wide range of morphologies, and high thermal and chemical stability. FBPCs have found immense use as cathode, anode and dual electrode materials for HICs in the recent literature. The current review is designed around two main concepts which include the synthesis and properties of FBPCs followed by their utilization in various types of HICs. Among monovalent HICs, lithium, sodium, and potassium, are given comprehensive attention, whereas zinc is the only multivalent HIC that is focused upon due to corresponding literature availability. Special attention is also provided to the critical factors that govern the performance of HICs. The review concludes by providing feasible directions for future research in various aspects of FBPCs and their utilization in HICs.

Recent advances in food waste-derived nanoporous carbon for energy storage.

Affordable and environmentally friendly electrochemically active raw energy storage materials are in high demand to switch to mass-scale renewable energy. One particularly promising avenue is the feasibility of utilizing food waste-derived nanoporous carbon. This material holds significance due to its widespread availability, affordability, ease of processing, and, notably, its cost-free nature. Over the years, various strategies have been developed to convert different food wastes into nanoporous carbon materials with enhanced electrochemical properties. The electrochemical performance of these materials is influenced by both intrinsic factors, such as the composition of elements derived from the original food sources and recipes, and extrinsic factors, including the conditions during pyrolysis and activation. While current efforts are dedicated to optimizing process parameters to achieve superior performance in electrochemical energy storage devices, it is timely to take stock of the current state of research in this emerging field. This review provides a comprehensive overview of recent developments in the fabrication and surface characterisation of porous carbons from different food wastes. A special focus is given on the applications of these food waste derived porous carbons for energy storage applications including batteries and supercapacitors.

This review compiles very recent literature on the synthesis of porous carbon from food waste biomass and their efficient utilisation as electrode material for energy storage applications in supercapacitor devices.

The Rise of Xene Hybrids.

Xenes, mono-elemental atomic sheets, exhibit Dirac/Dirac-like quantum behavior. When interfaced with other 2D materials such as boron nitride, transition metal dichalcogenides, and metal carbides/nitrides/carbonitrides, it enables them with unique physicochemical properties, including structural stability, desirable bandgap, efficient charge carrier injection, flexibility/breaking stress, thermal conductivity, chemical reactivity, catalytic efficiency, molecular adsorption, and wettability. For example, BN acts as an anti-oxidative shield, MoS2 injects electrons upon laser excitation, and MXene provides mechanical flexibility. Beyond precise compositional modulations, stacking sequences, and inter-layer coupling controlled by parameters, achieving scalability and reproducibility in hybridization is crucial for implementing these quantum materials in consumer applications. However, realizing the full potential of these hybrid materials faces challenges such as air gaps, uneven interfaces, and the formation of defects and functional groups. Advanced synthesis techniques, a deep understanding of quantum behaviors, precise control over interfacial interactions, and awareness of cross-correlations among these factors are essential. Xene-based hybrids show immense promise for groundbreaking applications in quantum computing, flexible electronics, energy storage, and catalysis. In this timely perspective, recent discoveries of novel Xenes and their hybrids are highlighted, emphasizing correlations among synthetic parameters, structure, properties, and applications. It is anticipated that these insights will revolutionize diverse industries and technologies.

Characterisation and agronomic evaluation of acidified food waste anaerobic digestate products.

Raw liquid anaerobic digestate was synthesised into nutrient-dense solid digestates via acidification and evaporation. Acidification retained ammonium in the digestate whilst also donating the anion to free ammonium to form an ammonium salt. Digestate was treated with the addition of sulphuric, nitric, and phosphoric acid resulting in the formation of ammonium sulphate, ammonium nitrate and ammonium phosphate, respectively then evaporated into a solid fertiliser product. FTIR, XRD and SEM-EDS collectively confirm that the addition of acids completely converted the free ammonium in the raw digestate into their respective ammonium salt counterparts. Compounds of potassium chloride, silicon dioxide, calcium carbonate, magnesium ammonium phosphate, sodium nitrate, and sodium chloride were identified in all solid digestate samples. Plant growth and grain yield was higher in urea ammonium nitrate, raw liquid digestate and acidified digestate products compared to control and unacidified solid digestate. Urea ammonium nitrate and ammonium nitrate solid digestate had the highest dry shoot, likely due to the high available nitrogen found in both fertilisers. Overall, acidification and evaporation of liquid digestate can efficiently transform it into a valuable solid fertiliser with a high nutrient density. This process not only has the potential to mitigate handling and storage constraints of low nutrient density digestate in anaerobic digestion facilities but also offers a sustainable alternative to conventional fertilisers.

ENVINet5 deep learning change detection framework for the estimation of agriculture variations during 2012-2023 with Landsat series data.

Remote sensing is one of the most important methods for analysing the multitemporal changes over a certain period. As a cost-effective way, remote sensing allows the long-term analysis of agricultural land by collecting satellite imagery from different satellite missions. Landsat is one of the longest-running world missions which offers a moderate-resolution earth observation dataset. Land surface mapping and monitoring are generally performed by incorporating classification and change detection models. In this work, a deep learning-based change detection (DCD) algorithm has been proposed to detect long-term agricultural changes using the Landsat series datasets (i.e., Landsat-7, Landsat-8, and Landsat-9) during the period 2012 to 2023. The proposed algorithm extracts the features from satellite data according to their spectral and geographic characteristics and identifies seasonal variability. The DCD integrates the deep learning-based (Environment for visualizing images) ENVI Net-5 classification model and posterior probability-based post-classification comparison-based change detection model (PCD). The DCD is capable of providing seasonal variations accurately with distinct Landsat series dataset and promises to use higher resolution dataset with accurate results. The experimental result concludes that vegetation has decreased from 2012 to 2023, while build-up land has increased up to 88.22% (2012-2023) for Landsat-7 and Landsat-8 datasets. On the other side, degraded area includes water (3.20-0.05%) and fallow land (1-0.59%). This study allows the identification of crop growth, crop yield prediction, precision farming, and crop mapping.

Bio-Inspired Supramolecular Self-Assembled Carbon Nitride Nanostructures for Photocatalytic Water Splitting.

Fast production of hydrogen and oxygen in large amounts at an economic rate is the need of the hour to cater to the needs of the most awaited hydrogen energy, a futuristic renewable energy solution. Production of hydrogen through simple water splitting via visible light photocatalytic approach using sunlight is considered as one of the most promising and sustainable approaches for generating clean fuels. For this purpose, a variety of catalytic techniques and novel catalysts have been investigated. Among these catalysts, carbon nitride is presently deemed as one of the best candidates for the visible light photocatalysis due to its unique molecular structure and adequate visible-range bandgap. Its bandgap can be further engineered by structural and morphological manipulation or by doping/hybridization. Among numerous synthetic approaches for carbon nitrides, supramolecular self-assembly is one of the recently developed elegant bottom-up strategies as it is bio-inspired and provides a facile and eco-friendly route to synthesize high surface area carbon nitride with superior morphological features and other semiconducting and catalytic properties. The current review article broadly covers supramolecular self-assembly synthesis of carbon nitride nanostructures and their photocatalytic water-splitting applications and provides a comprehensive outlook on future directions.

Biochar modulating soil biological health: A review.

Biochar can be used for multifunctional applications including the improvement of soil health and carbon storage, remediation of contaminated soil and water resources, mitigation of greenhouse gas emissions and odorous compounds, and feed supplementation to improve animal health. A healthy soil preserves microbial biodiversity that is effective in supressing plant pathogens and pests, recycling nutrients for plant growth, promoting positive symbiotic associations with plant roots, improving soil structure to supply water and nutrients, and ultimately enhancing soil productivity and plant growth. As a soil amendment, biochar assures soil biological health through different processes. First, biochar supports habitats for microorganisms due to its porous nature and by promoting the formation of stable soil micro-aggregates. Biochar also serves as a carbon and nutrient source. Biochar alters soil physical and chemical properties, creating optimum soil conditions for microbial diversity. Biochar can also immobilize soil pollutants and reduce their bioavailability that would otherwise inhibit microbial growth. However, depending on the pyrolysis settings and feedstock resources, biochar can be comprised of contaminants including polycyclic aromatic hydrocarbons and potentially toxic elements that can inhibit microbial activity, thereby impacting soil health.

Natural Products Derived Porous Carbons for CO2 Capture.

As it is now established that global warming and climate change are a reality, international investments are pouring in and rightfully so for climate change mitigation. Carbon capture and separation (CCS) is therefore gaining paramount importance as it is considered one of the powerful solutions for global warming. Sorption on porous materials is a promising alternative to traditional carbon dioxide (CO2 ) capture technologies. Owing to their sustainable availability, economic viability, and important recyclability, natural products-derived porous carbons have emerged as favorable and competitive materials for CO2 sorption. Furthermore, the fabrication of high-quality value-added functional porous carbon-based materials using renewable precursors and waste materials is an environmentally friendly approach. This review provides crucial insights and analyses to enhance the understanding of the application of porous carbons in CO2 capture. Various methods for the synthesis of porous carbon, their structural characterization, and parameters that influence their sorption properties are discussed. The review also delves into the utilization of molecular dynamics (MD), Monte Carlo (MC), density functional theory (DFT), and machine learning techniques for simulating adsorption and validating experimental results. Lastly, the review provides future outlook and research directions for progressing the use of natural products-derived porous carbons for CO2 capture.

Multifunctional carbon nitride nanoarchitectures for catalysis.

Catalysis is at the heart of modern-day chemical and pharmaceutical industries, and there is an urgent demand to develop metal-free, high surface area, and efficient catalysts in a scalable, reproducible and economic manner. Amongst the ever-expanding two-dimensional materials family, carbon nitride (CN) has emerged as the most researched material for catalytic applications due to its unique molecular structure with tunable visible range band gap, surface defects, basic sites, and nitrogen functionalities. These properties also endow it with anchoring capability with a large number of catalytically active sites and provide opportunities for doping, hybridization, sensitization, etc. To make considerable progress in the use of CN as a highly effective catalyst for various applications, it is critical to have an in-depth understanding of its synthesis, structure and surface sites. The present review provides an overview of the recent advances in synthetic approaches of CN, its physicochemical properties, and band gap engineering, with a focus on its exclusive usage in a variety of catalytic reactions, including hydrogen evolution reactions, overall water splitting, water oxidation, CO2 reduction, nitrogen reduction reactions, pollutant degradation, and organocatalysis. While the structural design and band gap engineering of catalysts are elaborated, the surface chemistry is dealt with in detail to demonstrate efficient catalytic performances. Burning challenges in catalytic design and future outlook are elucidated.

Utilising the Nanozymatic Activity of Copper-Functionalised Mesoporous C3 N5 for Sensing Biomolecules.

Designing unique nanomaterials for the selective sensing of biomolecules is of significant interest in the field of nanobiotechnology. In this work, we demonstrated the synthesis of ordered Cu nanoparticle-functionalised mesoporous C3 N5 that has unique peroxidase-like nanozymatic activity for the ultrasensitive and selective detection of glucose and glutathione. A nano hard-templating technique together with the in-situ polymerisation and self-assembly of Cu and high N-containing CN precursor was adopted to introduce mesoporosity as well as high N and Cu content in mesoporous C3 N5 . Due to the ordered structure and highly dispersed Cu in the mesoporous C3 N5 , a large enhancement of the peroxidase mimetic activity in the oxidation of a redox dye in the presence of hydrogen peroxide could be obtained. Additionally, the optimised Cu-functionalised mesoporous C3 N5 exhibited excellent sensitivity to glutathione with a low detection limit of 2.0 ppm. The strong peroxidase activity of the Cu-functionalised mesoporous C3 N5 was also effectively used for the sensing of glucose with a detection limit of 0.4 mM through glucose oxidation with glucose oxidase. This unique Cu-functionalised mesoporous C3 N5 has the potential for detecting various molecules in the environment as well as for next-generation glucose and glutathione diagnostic devices.

Organocatalysis with carbon nitrides.

Carbon nitrides, a distinguished class of metal-free catalytic materials, have presented a good potential for chemical transformations and are expected to become prominent materials for organocatalysis. This is largely possible due to their low cost, exceptional thermal and chemical stability, non-toxicity, ease of functionalization, porosity development, etc. Especially, the carbon nitrides with increased porosity and nitrogen contents are more versatile than their bulk counterparts for catalysis. These N-rich carbon nitrides are discussed in the earlier parts of the review. Later, the review highlights the role of such carbon nitride materials for the various organic catalytic reactions including Knoevenagel condensation, oxidation, hydrogenation, esterification, transesterification, cycloaddition, and hydrolysis. The recently emerging concepts in carbon nitride-based organocatalysis have been given special attention. In each of the sections, the structure-property relationship of the materials was discussed and related to their catalysis action. Relevant comparisons with other catalytic materials are also discussed to realize their real potential value. The perspective, challenges, and future directions are also discussed. The overall objective of this review is to provide up-to-date information on new developments in carbon nitride-based organic catalysis reactions that could see them rising as prominent catalytic materials in the future.

Recent Advances in Carbon-Based Electrodes for Energy Storage and Conversion.

Carbon-based nanomaterials, including graphene, fullerenes, and carbon nanotubes, are attracting significant attention as promising materials for next-generation energy storage and conversion applications. They possess unique physicochemical properties, such as structural stability and flexibility, high porosity, and tunable physicochemical features, which render them well suited in these hot research fields. Technological advances at atomic and electronic levels are crucial for developing more efficient and durable devices. This comprehensive review provides a state-of-the-art overview of these advanced carbon-based nanomaterials for various energy storage and conversion applications, focusing on supercapacitors, lithium as well as sodium-ion batteries, and hydrogen evolution reactions. Particular emphasis is placed on the strategies employed to enhance performance through nonmetallic elemental doping of N, B, S, and P in either individual doping or codoping, as well as structural modifications such as the creation of defect sites, edge functionalization, and inter-layer distance manipulation, aiming to provide the general guidelines for designing these devices by the above approaches to achieve optimal performance. Furthermore, this review delves into the challenges and future prospects for the advancement of carbon-based electrodes in energy storage and conversion.

Coping strategies and emotional responses adopted by health care workers during COVID-19 pandemic-braving the storm.

Background and Aims: Health care workers (HCWs) are caught in the middle of the COVID-19 pandemic storm and are exposed to a large degree of physical and emotional stress. This study was planned to describe the stressors, stress levels, emotional responses, and coping strategies adopted by HCWs amidst this pandemic. Material and Methods: This cross-sectional, web-based survey was conducted after ethics approval, using a structured performa incorporating standardized stress (PSS-10 C), emotional responses (PANAS-10), and coping strategy (Brief COPE) scales. The snowball sampling technique was used to conduct the study and collect data. Data were analyzed using SPSS 26 version (SPSS Inc., Chicago, IL, USA) statistical software. A P value of <0.05 was considered significant. Results: Out of 402 participants (65% doctors and 35% nurses), 87% perceived moderate stress levels, and nearly half of the participants were interns, residents, and medical officers. Infection to self or family members (77.1%), survival of sick patients (75.6%), aggression by patients and relatives (70.3%), and long duty hours (67%) were some of the major stressors as reported by HCWs. The most common positive emotion felt was being alert (19.17 ± 5.57) and negative emotion perceived was being upset (15.6 ± 6.06). Many participants adopted emotion and problem-focused coping strategies such as planning and strategization (68%) and positive reframing (67.6%), whereas dysfunctional coping strategies such as venting and denial were adopted less commonly. Conclusion: Moderate stress levels perceived by HCWs are a cause for concern. Emotional responses of HCWs to stress vary; however, appropriate coping strategies including emotional and problem-focused coping strategies are the need of the hour to tackle pandemic-related stress.

Advanced nanomaterials for highly efficient CO2 photoreduction and photocatalytic hydrogen evolution.

At present, CO2 photoreduction to value-added chemicals/fuels and photocatalytic hydrogen generation by water splitting are the most promising reactions to fix two main issues simultaneously, rising CO2 levels and never-lasting energy demand. CO2, a major contributor to greenhouse gases (GHGs) with about 65% of the total emission, is known to cause adverse effects like global temperature change, ocean acidification, greenhouse effects, etc. The idea of CO2 capture and its conversion to hydrocarbons can control the further rise of CO2 levels and help in producing alternative fuels that have several further applications. On the other hand, hydrogen being a zero-emission fuel is considered as a clean and sustainable form of energy that holds great promise for various industrial applications. The current review focuses on the discussion of the recent progress made in designing efficient photocatalytic materials for CO2 photoreduction and hydrogen evolution reaction (HER). The scope of the current study is limited to the TiO2 and non-TiO2 based advanced nanomaterials (i.e. metal chalcogenides, MOFs, carbon nitrides, single-atom catalysts, and low-dimensional nanomaterials). In detail, the influence of important factors that affect the performance of these photocatalysts towards CO2 photoreduction and HER is reviewed. Special attention is also given in this review to provide a brief account of CO2 adsorption modes on the catalyst surface and its subsequent reduction pathways/product selectivity. Finally, the review is concluded with additional outlooks regarding upcoming research on promising nanomaterials and reactor design strategies for increasing the efficiency of the photoreactions.

Metal nitride-based nanostructures for electrochemical and photocatalytic hydrogen production.

The over-dependence on fossil fuels is one of the critical issues to be addressed for combating greenhouse gas emissions. Hydrogen, one of the promising alternatives to fossil fuels, is renewable, carbon-free, and non-polluting gas. The complete utilization of hydrogen in every sector ranging from small to large scale could hugely benefit in mitigating climate change. One of the key aspects of the hydrogen sector is its production via cost-effective and safe ways. Electrolysis and photocatalysis are well-known processes for hydrogen production and their efficiency relies on electrocatalysts, which are generally noble metals. The usage of noble metals as catalysts makes these processes costly and their scarcity is also a limiting factor. Metal nitrides and their porous counterparts have drawn considerable attention from researchers due to their good promise for hydrogen production. Their properties such as active metal centres, nitrogen functionalities, and porous features such as surface area, pore-volume, and tunable pore size could play an important role in electrochemical and photocatalytic hydrogen production. This review focuses on the recent developments in metal nitrides from their synthesis methods point of view. Much attention is given to the emergence of new synthesis techniques, methods, and processes of synthesizing the metal nitride nanostructures. The applications of electrochemical and photocatalytic hydrogen production are summarized. Overall, this review will provide useful information to researchers working in the field of metal nitrides and their application for hydrogen production.

Recovery, regeneration and sustainable management of spent adsorbents from wastewater treatment streams: A review.

Adsorption is the most widely adopted, effective, and reliable treatment process for the removal of inorganic and organic contaminants from wastewater. One of the major issues with the adsorption-treatment process for the removal of contaminants from wastewater streams is the recovery and sustainable management of spent adsorbents. This review focuses on the effectiveness of emerging adsorbents and how the spent adsorbents could be recovered, regenerated, and further managed through reuse or safe disposal. The critical analysis of both conventional and emerging adsorbents on organic and inorganic contaminants in wastewater systems are evaluated. The various recovery and regeneration techniques of spent adsorbents including magnetic separation, filtration, thermal desorption and decomposition, chemical desorption, supercritical fluid desorption, advanced oxidation process and microbial assisted adsorbent regeneration are discussed in detail. The current challenges for the recovery and regeneration of adsorbents and the methodologies used for solving those problems are covered. The spent adsorbents are managed through regeneration for reuse (such as soil amendment, capacitor, catalyst/catalyst support) or safe disposal involving incineration and landfilling. Sustainable management of spent adsorbents, including processes involved in the recovery and regeneration of adsorbents for reuse, is examined in the context of resource recovery and circular economy. Finally, the review ends with the current drawbacks in the recovery and management of the spent adsorbents and the future directions for the economic and environmental feasibility of the system for industrial-scale application.

Nanoporous materials for pesticide formulation and delivery in the agricultural sector.

One of the key focuses of the agricultural industry for preventing the decline in crop yields due to pests is to develop effective, safe, green, and sustainable pesticide formulation. A key objective of industry is to deliver active ingredients (AIs) that have minimal off site migration and non-target activity. Nanoporous materials have received significant attention internationally for the efficient loading and controlled, targeted delivery of pesticides. This is largely made possible due to their textural features including high surface area, large pore-volume, and tunable pore size. Additionally, the easier manipulation of their surface chemistry and stability in different environments are added advantages. The unique features of these materials allow them to address the solubility of the active ingredients, their efficient loading onto the porous channels, and slow and controlled delivery over time. One of their major advantages is the wide range of materials that could be suitably designed via different approaches to either adsorb, encapsulate, or entrap the active ingredient. This review is a timely presentation of recent progress made in nanoporous materials and discusses critical aspects of pesticide formulation and delivery.