Alternative Energy Resources Research Articles

Graphene Quantum Dots: Novel Properties and Their Applications for Energy Storage Devices.

Batteries and supercapacitors are the next-generation alternative energy resources that can fulfil the requirement of energy demand worldwide. In regard to the development of efficient energy storage devices, various materials have been tested as electrode materials. Graphene quantum dots (GQDs), a new class of carbon-based nanomaterial, have driven a great research interest due to their unique fundamental properties. High conductivity, abundant specific surface area, and sufficient solubility, in combination with quantum confinement and edge effect, have made them appropriate for a broad range of applications such as optical, catalysis, energy storage and conversion. This review article will present the latest research on the utilization of GQDs and their composites to modify the electrodes used in energy storage devices. Several major challenges have been discussed and, finally, future perspectives have been provided for the better implementation of GQDs in the energy storage research.

Evaluation of Chemical Composition of Miscanthus × giganteus Raised in Different Climate Regions in Russia.

Lignocellulosic biomass is of great interest as an alternative energy resource because it offers a range of merits. Miscanthus × giganteus is a lignocellulosic feedstock of special interest, as it combines a high biomass productivity with a low environmental impact, including CO2 emission control. The chemical composition of lignocellulose determines the application potential for efficient industrial processing. Here, we compiled a sample collection of Miscanthus × giganteus that had been cultivated in different climate regions between 2019 and 2021. The chemical composition was quantified by the conventional wet methods. The findings were compared with each other and with the known data. Starting as soon as the first vegetation year, Miscanthus was shown to feature the following chemical composition: 43.2–55.5% cellulose content, 17.1–25.1% acid-insoluble lignin content, 17.9–22.9% pentosan content, 0.90–2.95% ash content, and 0.3–1.2% extractives. The habitat and the surrounding environment were discovered herein to affect the chemical composition of Miscanthus. The stem part of Miscanthus was found to be richer in cellulose than the leaf (48.4–54.9% vs. 47.2–48.9%, respectively), regardless of the planation age and habitat. The obtained findings broaden the investigative geography of the chemical composition of Miscanthus and corroborate the high value of Miscanthus for industrial conversion thereof into cellulosic products worldwide.

Facile synthesis of Er-MOF/Fe2O3 nanocomposite for oxygen evolution reaction

Currently, energy disasters and environmental contamination are of worldwide concern, and to replace the dependency on fossil fuels, it is required to use a different alternate energy resource. to confirm a green and sustainable future. In the current effort, simple Er-MOF and its nanocomposite (Er-MOF/Fe2O3) were manufactured through hydrothermal method which freshly produced on the conducting surface of NF (Nickle Foam) for OER (oxygen evolution reaction) in 1.0 M KOH electrolyte. The synthesized materials were determined through various analytical methods to study the structure, porosity and morphology by using X-ray Diffraction Analysis (XRD), Brunauer Emmet-Teller (BET) and Scanning Electron Microscopy (SEM), and studies, respectively. The water-splitting measurement of the fabricated composite material showed the outstanding oxygen activity for oxygen evolution reaction and observed lower overpotential of 216 mV to achieve a current density of 10 mA/cm2, a lower onset potential of 1.43 V through lower Tafel slope of 47 mV/dec. Hence, present effort may present a novel opportunity. avenue for OER.

Assessing the role of natural resource utilization in attaining select sustainable development goals in the era of digitalization

PurposeThe objective of this study is to conduct a comprehensive review of the existing literature in order to examine how digital technologies are used to effectively utilize natural resources. Design/Methodology/ApproachThe paper employs a two-level analytical approach that includes bibliometric analysis and an integrative literature review comprising of mechanical analysis and manual interpretation of 138 publications from the Web of Science (WoS) database. FindingsThe findings identify the most influential articles, and sources on the subject based on their publication, citation, and importance to the intellectual network; additionally, the study sheds light on the subject's intellectual structure (thematic analysis), which is supported by seven major clusters focusing on ‘water resource management,’ ‘environmental impact,’ ‘economic and social impact,’ ‘technological innovation and digitalization,’ ‘circular economy,’ ‘alternative energy resources,’ and ‘energy resource management’. OriginalityTo the best of our knowledge, this is the first integrative review of its kind that provides a thorough examination of the literature on the natural resource utilization in digital era in attaining select SDGs. We conducted an inductive analysis and built aggregate dimensions from the study's core subjects and themes using keyword co-occurrence and thematic analysis, which led to a conceptual framework for integrating natural resource utilization and SDGs. Our conceptual framework synthesizes how innovation, digitization, and technology transfer and dissemination contribute to resource management and sustainable use, achieving SDGs.

Analysis of Particulate Matter Emissions and Performance of the Compression Ignition Engine Using Biodiesel Blended Fuel

As the world becomes more urbanized, the market for petroleum products increases. The supply of crude oil-based products such as diesel, gasoline, and natural gas is limited. Furthermore, natural resources are finite and their reservoirs are located in certain parts of the globe. Countries with low to no fossil fuel resources are experiencing a scarcity of petroleum products, necessitating the exploration of alternative energy resources. In this research, tests regarding the exhaust particulate emission, sound pressure level, and performance have been carried out using samples from diesel and biodiesel (waste cooking oil) blended fuel. Two fuel samples have been used, B25 (biodiesel 25% and 75% diesel) and 100% diesel as a baseline in a CI engine at constant RPM of 1350 and variable loads of 0.0 to 1.6 at an interval of 0.2Kg-m. The results show that particulate emissions are reduced by about 7.29% when using biodiesel blended fuel, whereas brake-specific fuel consumption of biodiesel blended fuel has decreased as brake power increased, and brake thermal efficiency increased as brake power increased. The sound pressure level was measured from different locations of the engine (back, front, left) and for varying load. The results show that B25 produces less noise than D100 in each case.

Generation of Hybrid Energy System (Solar-Wind) Supported with Battery Energy Storage

Abstract: The utilization of renewable energy is significantly important for the world because global energy consumption is increasing, while conventional energy sources are no longer sufficient to meet the energy demand, triggering energy crises. In recent years, the increasing prices of fossil fuels and concerns about the environmental consequences of greenhouse gas emissions have renewed the interest in the development of alternative energy resources. Renewable energy is now considered a more desirable source of fuel than nuclear power due to the absence of risk and disasters [1]. Considering that the major component of greenhouse gases is carbon dioxide, there is a global concern about reducing carbon emissions. In this regard, different policies could be applied to reducing carbon emissions, such as enhancing renewable energy deployment and encouraging technological innovations. There are various of renewable energy sources such as Solar, biomass, wind, hydrogen, fuel cell, nanocomposite, and supercapacitor. Each of the energy sources are suitable for specific geographical locations and can suits from region to region. However, variation in solar radiation and wind speed caused by climate and weather conditions restricts the stable operation of renewable energy systems, therefore, causing the output to fluctuate. A hybrid renewable energy generation system can be highly efficient by combining multiple renewable energy sources and is regarded as a promising solution to overcome from this issue. Hybrid solar systems are the systems combining two renewable sources of energy, like solar and wind. Then, energy is generated through solar on sunny days and when there is limited sunshine but there is wind, energy can be generated through it. The study aims to focus on generation of hybrid solar-wind power plant with the optimal contribution of renewable energy resources supported by battery energy storage technology. The motivating factor behind the hybrid solar–wind power system design is the fact that both solar and wind power exhibit complementary power profiles. Advantageous combination of solar and wind with optimal ratio will lead to clear benefits for hybrid solar-wind power plants such as smoothing of intermittent power, higher reliability, and availability. However, the potential challenges for its integration into power grids cannot be neglected. A potential solution is to utilise one of the energy storage technologies, though all of them are still very expensive for such applications, especially at large scale. Therefore, optimal capacity calculations for energy storage system are also vital to realise full benefits. Currently, battery energy storage technology is considered as one of the most promising choices for renewable power applications. However, solar-wind power technology are most suitable for off-grid services, serving the remote are without having to build or extend expensive and complicated grid infrastructure. Therefor standalone system using renewable energy sources have become a preferred option. Hence hybrid energy systems are an ideal solution since they can offer substantial improvements in performance and cost reduction and can be tailored to varying end user requirements

Cluster Fig (Ficus racemosa Linn): A sustainable renewable source for Bioethanol Production by Fermentation

Increased demand and remarkable rise in prices of petroleum products have resulted in the need to discover alternative energy resources to satisfy the energy demand of the world. Bioethanol has been recognized as the most used biofuel globally since it is known to contribute in the reduction in crude oil consumption and global environmental pollution. Bioethanol can be produced from feedstock such as starch, sucrose, lignocellulosic and algal biomass through the fermentation process by microbes. Hence, the main objective is to satisfy this requirement leading to the development of easier methods using inexpensive and eco-friendly raw materials for the bioethanol production. In the present investigations, production of bioethanol from Ficus racemosa L. (Cluster fig), using active Saccharomyces cerevisiae (baker's yeast) strain was examined. The organolepsis, miscibility, boiling point, pH, specific gravity, combustion test, tri-iodomethane test and the reducing sugar of Ficus racemosa fruits were determined. Parameters such as pH, temperature, fermentation period, yeast concentration and yeast supplements were optimized for ethanol production. Bioethanol was obtained by double distillation process after the fermentation reaction of fruits. The results show that the maximum rate of ethanol production through fermentation of Ficus racemosa fruit waste by Saccharomyces cerevisiae increases with the fermentation period and yeast concentration at 30°C in 120hrs.

Effective excitons separation in starfish Bi2S3/TiO2 nanostructures for enhanced hydrogen production

Water Splitting into gaseous hydrogen and oxygen through photocatalytic and electrocatalytic methods are notable alternative energy resources as it operates under ambient temperature/pressure that showed enormous potential to meet the clean energy demands. Hierarchical decoration of nano-size TiO2 on Bi2S3 (Bi2S3@TiO2) having starfish morphology with a varied amount of TiO2 are synthesized by one-pot hydrothermal method both semiconducting and catalytic properties of pristine and Bi2S3@TiO2 hierarchical nanostructures are thoroughly characterized and discussed by using structural, optical, morphological, electronic, surface and bulk elemental composition analysis. Heterojunction formed between Bi2S3 and TiO2 promotes suppression of photo charge carrier recombination and facilitated fast transportation of charge carriers in turn promoted oxidation and reduction reactions at catalytic active sites. The optimized photocatalyst Bi2S3@TiO2 displayed a large surface area of 38.6 m2 g−1 and plenty of catalytic active sites facilitated a high turn-over frequency of 0.085 cm−1. Further, the optimal experimental conditions, a high rate of H2 evolution of 44.1 mmol h−1 g−1cat under UV–visible light to the hydrogen conversion efficiency was calculated as 21.7%. Consequently, the electrochemical measurements of the Bi2S3@TiO2 a significantly HER overpotential of 222/332 mV to achieve a current density of 20/50 mA cm−2. As a result, enhanced efficiency of Bi2S3@TiO2/NF is demonstrated for H2 evolution in an alkaline medium. The overall water splitting performance is attributed to available plenty of catalytic active sites. Thus, the prepared composite showed enhanced stability for prolonged usage for 50 h of light irradiation. These results will open up opportunities to develop low-cost and earth-abundant efficient electrode materials for multi-functional applications.

Re-visiting Geothermal Fluid Circulation, Reservoir Depth and Temperature of Geothermal Springs of India

• Most of the thermal water are of immature water type. • Four major water types were identified in four major geothermal provinces. • For the Himalayan springs, water–rock interaction are dominant at depths. • The reservoir temperature of the Himalayan and the west coast springs are higher. • The fluid circulation depth for the Himalayas are deeper (∼2.14 km). Stringent pollution control regulations and sustainable development goals have renewed the interest in finding an alternate, renewable, and sustainable energy resource. Geothermal energy is one such potential source, which needs to be explored. This study deals with the geochemical characteristics and reservoir parameters of the major hot springs located in four diverse terrains in India, as well as their energy potential in terms of reservoir temperature. The west coast springs have mostly Na-Cl, Ca-SO 4 , and Na-HCO 3 water types, and are likely to be influenced by seawater intrusion through deep penetrating faults and fractures, whereas the Odisha hot springs show immature water of Na-Cl, Ca-HCO 3 types. The West Bengal springs show Na-Cl-HCO 3 water type, presumably derived from dissolution of albite at higher temperatures at depths (∼1.13 km). The Himalayan springs water are mostly of NaHCO 3 , CaHCO 3 , NaCl, and CaSO 4 types, and are geochemically more diversified compared to the west coast, West Bengal, and Odisha hot springs. The estimated reservoir temperatures and reservoir depths are 150 ± 10 °C, and 2.11 ± 0.2 km; 120 ± 5 °C, and 1.71 ± 0.17 km; 100 ± 5 °C and 1.13 ± 0.13 km; 110 ± 5 °C and 1.37 ± 0.32 km for the Himalayan, west coast, West Bengal and the Odisha geothermal systems, respectively.

Transition from traditional energy to renewable energy: assessment of the contribution of renewable energy in greenhouse gas emissions reduction on the example of the Yereimentau wind farm

Kazakhstan has a high potential for creating international-class green energy, but at the moment alternative energy resources are used in a small amount due to various technical, administrative, social and economic obstacles. This work is devoted to the analysis of the share of renewable energy generated in the total volume of electricity production in Kazakhstan, the amount of electricity produced by renewable energy facilities is estimated. Also in this paper, an assessment of greenhouse gas emissions reductions was carried out on the example of the largest wind power plant in Kazakhstan with a capacity of 45 MW in the city of Yerementau. The share of renewable energy sources in the country’s energy balance was estimated by comparison. The annual data on the generation of electric energy by renewable energy facilities for 2016-2021 are compared according to the statistical data of the Republic of Kazakhstan. A methodological approach to the calculation of greenhouse gas emissions reductions based on a baseline scenario is proposed, which can be used as a methodology for calculating greenhouse gas emissions reductions at renewable energy facilities. Assessment of reductions in greenhouse gas emissions as a result of the implementation of renewable energy projects is important both for calculating the national carbon balance of the country as a whole and for accurately calculating the units of reductions planned to be issued as a result of the implementation of these projects. The Yerementau wind power plant will help the Republic of Kazakhstan in achieving the goals set ahead – increasing the share of renewable energy sources and reducing carbon dioxide emissions. Key words: renewable energy sources (RES), emission reduction, wind power, greenhouse gases, emission factor.

Tracing volatility in natural resources, green finance and investment in energy resources: Fresh evidence from China

The role of natural resources on economic growth and financial development is debated. Due to its influence on the economy, natural resource volatility is a significant concern for researchers and policymakers. Volatility in other areas, including energy investment and green finance, might affect economic, financial, and environmental indicators, which needs attention in modern times as the literature remains silent. To bridge the gap, the current study aims to identify volatility in natural resources, energy investment, and green finance. Due to the data unavailability issue, this study analyzes only the last three decades, i.e., from 1990 to 2020. Using traditional and appropriate volatility measures, i.e., autoregressive conditional heteroscedasticity (ARCH), the results asserted that natural resources and energy investment are volatile across time. In contrast, no volatility is evident in green finance. This study employed the threshold generalized autoregressive conditional heteroscedasticity TGARCH(1, 1) specification to analyze the shocks' asymmetry. The estimated results uncover that the negative shock in natural resources could lead to higher volatility than the positive shock. However, no asymmetry exists between the positive and negative shocks in energy investment. This study suggests the financial sector's stability and natural resource prices based on the empirical findings. Also, this study recommends that investment in energy resources be diversified by developing alternative energy resources, and green finance investment must be enhanced. This study empirically links financial sector stability and natural resource pricing. This study advises growing alternate energy resources and increasing green finance investment.

Energy Security, Sustainable Development and the Green Bond Market

Many countries are pursuing energy security (ES) in their economies while implementing sustainable development goals (SDGs). Relevant policies may include: (1) access to efficient alternative and preferably renewable energy sources (RESs); and (2) reductions in conventionally obtained energy consumption. As the demand for energy is growing and alternative energy resources are expensive, new ways of financing projects to improve ES are of special interest, e.g., issuing green bonds. In such cases, the obtained funds are allocated to projects that can both improve ES and help to achieve SDGs. The aim of the study was to explore the dependences (in the sense of Granger causality) between the green bond (GB) market, different aspects of sustainable development, as measured by global indicators taken from a family of environmental NASDAQ OMX indices, and ES represented by crude oil prices. The methodology is based on the vector autoregression model. The findings reveal evidence of a short-term dependence between the GB market, ES and the multidimensional nature of sustainable development.

Advanced efficiency improvement of a sloping wall oscillating water column via a novel streamlined chamber design

Despite the huge potential of ocean waves as an alternative renewable energy resource, very low wave to wire efficiency of wave energy converters (WECs) hampers its commercialization. In this study, a novel streamlined chamber design has been proposed for performance improvement of an oscillating water column (OWC) with a sloping wall. Physical experiments are carried out for the calculation of capture width ratio (CWR) as a measure of hydrodynamic performance for various levels of PTO damping and sea conditions. The results are compared with those of a classical OWC chamber design. It is found that streamlined chamber design has an important bearing on OWC efficiency. As opposed to classical chamber shape, proposed streamlined chamber geometry increases the OWC performance as much as 31% for the incident waves under which the OWC operates efficiently. Further, results show that optimal level of PTO damping that for utmost energy extraction depends on the chamber design. Streamlined chamber geometry even further improves the OWC efficiency even when dominant sloshing water column motion is present in the chamber with a maximum and average value of 54% and 44%, respectively, however, chamber design has no influence on the mechanism that generates sloshing phenomenon in the chamber.

Alternative energy and natural resources in determining environmental sustainability: a look at the role of government final consumption expenditures in France.

The global community is concerned about several environmental changes. Climate change, desertification, destruction of tropical rainforests, erosion of coastal ecosystems, soil resource loss, overfishing, species extinction, and loss of biodiversity are all contributing factors. Many commentators contend that these issues make up a cumulative, sustained human impact on the environment that has profoundly changed the surface of the Earth. We explore the effects of alternative energy sources, natural resources, and government consumption expenditures on French environmental sustainability from 1990 through 2018 under the environmental Kuznets curve (EKC) framework. We apply advanced econometric methodologies for empirical analysis. Our long-run estimates indicate that alternative and nuclear energy, natural resources, and government final consumption expenditures are negatively associated with CO2 emissions, while economic growth is positively related to CO2 emissions. CO2 emissions are negatively correlated with the square root of economic growth (EKC), thereby supporting EKC. As economic growth increases, environmental sustainability deteriorates. Eventually, EKC will make a positive contribution to environmental improvement. Future research directions, research limitations, and policy implications are discussed.

ASSESSMENT OF SURPLUS CROP RESIDUE BIOMASS ENERGY SECTOR: INDIA

This paper deals with three issues related to surplus residues biomass energy: 1. the concept of surplus crop residues biomass energy, 2. institutional setup for residues biomass energy policy and planning, and 3. Its achievement at the national level. The choice of surplus crop residues biomass energy is dependent on the institutional framework that shaped its existence in the renewable energy sector. The current study is shaped by various alternative learning-based approaches used by academics and practitioners in the field of renewable energy. The approaches show similarities with Clean Development Management (CDM) goals and reflect the alternative and sustainable development context within which they were framed toward ecological-based energy capacity building. The institutional framework can encourage surplus crop residual biomass energy, and it is one of the few alternative energy resources in which individuals appear eager to invest. However, the surplus crop residues biomass energy initiative is slowly spreading across the country, wait and watch if the surplus crop residues biomass energy approach can prove its merits.

PRESENT DEVELOPMENT OF ANODE MATERIALS IN LITHIUM-ION BATTERIES: A REVIEW

Recently the world is suffering from insufficiency of natural energy resources in comparison to higher energy consumption, lack of environmental health (Climate change, Air-pollution, plastic waste and so on) and the sudden enhanced usage of- portable electronics, electric vehicles, HEV on daily bases- motivates scientist to invent new, efficient, clean and low-cost alternative energy resources such as- Lithium Ion Battery. On account of high capacity, fast charge-discharge rates, light weight, long lifetime, high stability Lithium-ion batteries are very promising energy storage devices. Their great electrochemical performance makes them commercially viable. These rechargeable batteries have proved themselves as a rising star and contain a lot more potential to fulfil the future energy requirements. This paper will highlight a review on Li-ion Batteries from their birth till now, the growth and increments on their fabrication techniques and represents advantages of carbonic anodes. It also gives us an idea about why carbon-based nanostructures (graphite, graphene, CNTs, CQDs, and GQDs) and their composites are the best choice of anode materials for Li-ion Batteries. We hope to present a brief knowledge about different carbon-based anode with comprehensive study of different anodic materials which were already available in the literature.

Developing offshore natural gas hydrate from existing oil & gas platform based on a novel multilateral wells system: Depressurization combined with thermal flooding by utilizing geothermal heat from existing oil & gas wellbore

Offshore natural gas hydrate (NGH) is universally recognized as a new alternative energy resource. If methods can be found to commercially exploit it, it is expected to significantly impact the world's energy supply. In this work, an innovative method for developing offshore NGH from existing oil & gas platform is proposed, namely depressurization combined with thermal flooding utilizing geothermal heat from existing oil & gas wellbore based on a novel multilateral wells system. Meanwhile, a numerical simulation model is developed to investigate the natural gas recovery performance of the proposed method. The study shows that the average NGH concentration of the whole NGH bearing layer is reduced by about 25% after one year production by utilizing the innovative method, and 1.6 × 107 m3 natural gas is produced. Bottom hole pressure is the main controlling factor in the initial stage of NGH dissociation, while the formation temperature is the main controlling factor for the dissociation of NGH in the later stage of production, and increasing the fluid injection rate is an effective means to enhance the production performance. The study also shows that the production mode of continuous injection-intermittent production has the highest cumulative natural gas production, its production performance is proved to be the best.

Novel Epoxy-Free Imaging of the Proton Exchange Membrane Fuel Cell Components and Microstructure Degradation By Transmission Electron Microscopy

Performance, durability, and efficiency limitations of proton exchange membrane fuel cells (PEMFCs), as one of the alternative clean energy resources, has been hindering the widespread adoption of these devices. Improving those parameters is closely entangled with identifying the degradation mechanism of each component in the electrodes i.e., catalyst – commonly platinum nanoparticles, catalyst support – carbon, and the ion conductive polymer – ionomer, as well as the effects that degradation can have on the porous network of the electrodes[1]. Degradation during typical automotive operation protocols like startup/shut down (SUSD)[2,3] is of a special interest. Therefore, it is essential to observe the changes of the microstructure, as whole, and each individual component’s response to the working condition, in order to understand degradation mechanisms and devise degradation mitigation strategies. Transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) in conjunction with energy dispersive spectroscopy (EDS) have proven to be valuable tools in unravelling the complex changes of the microstructure and understanding of the degradation mechanisms[4]. Moreover, correlating the numerical microstructural descriptors, extracted by quantification of the TEM and EDS results, with the visual observations helped the research community to draw a connection between the degradation and microstructural changes[5]. However, the conventionally prepared TEM samples by slicing (microtomy) an epoxy-embedded piece of a catalyst coated membrane (CCM) have limitations in observing carbon and ionomer, and distinguishing them from each other and from the epoxy. Partial epoxy-embedding showed very promising results regarding distinguishing carbon from ionomer in selected regions of the CCM[6]. However, not a full CCM was observed. Therefore, we report for the first time, an epoxy-free microtomy approach for a whole CCM, successfully implemented on a fresh and degraded cathode layer of beginning-of-life (BOL) and SUSD samples, respectively. Electrochemical characterization of the samples presented here are discussed in previous publication[2]. The Pt catalyst, carbon, ionomer and porous network of the cathodes were clearly observable and distinguishable in both BOL and SUSD samples using high-resolution TEM and 3D electron tomography-TEM (ET-TEM) imaging. The microstructural comparison revealed the changes in Pt particles distribution – moving into the ionomer network rather than sitting on and inside the carbon support, disintegration of corroded carbon and dispersion of broken-off graphitic carbon pieces in the ionomer, and alteration of the ionomer network – formation of more ionomer filaments. In addition, ET-TEM of the BOL and SUSD samples confirmed the presence of Pt particles inside the amorphous core of the carbon particle and their migration during SUSD operation, respectively. Finally, the visual results were correlated with the microstructural descriptors quantified using our proprietary quantification technique. The numerical microstructure properties corroborated the observations that was made based on the TEM images observations. Therefore, implementation of whole-CCM-epoxy-free microtomy technique can be considered as a novel method in aiding the research community in understanding the degradation mechanism and microstructural properties alteration.

On the Study of Lithium Diffusivity in Lithium Nickel Manganese Cobalt Oxide Cathodes

Climate change, population growth, and rising fossil fuel prices have encouraged governments and scientists for alternate energy resources. This energy transition requires a high-performance energy storage device to satisfy the high energy and power demand and lithium-ion battery (LIB) is one of the promising one. The performance of these batteries ultimately relies on the properties of their components. In this regard, to meet the high-power demand in high-power applications (such as electric vehicles (EVs) and hybrid EVs), materials with rapid lithium transport are required. Lithium Nickel Manganese Cobalt Oxide (NMC) has attracted scientists’ attentions due to its outstanding performance as a cathode material. Therefore, understanding the effect of various factors on lithium diffusivity in NMC is critical to develop high-performance LIBs for high-power applications.Electrochemical methods such as potentiostatic and galvanostatic intermittent titration techniques (PITT and GITT) have been frequently utilized to experimentally quantify lithium diffusivity in NMC. These techniques need the knowledge of electrode particle shape and dimension, and uncertainty about these parameters leads to substantial errors in predicting the diffusion coefficient. In addition, because these techniques consider the response of the whole electrochemical cell, it is hard to distinguish the effect of different structural factors on Li diffusivity in a single NMC active material. Therefore, an appropriate method still needs to be developed to capture the structural effects on lithium diffusivity in NMC. For this purpose, a multi-level modelling from Density Functional Theory (DFT) to kinetic Monte Carlo (KMC) should be implemented.In this study, we will use DFT to find the ground state energy of NMC at different lithium concentrations and configurations. Also, the minimum energy path of lithium migration and the related activation barrier will be found by Climbing Image-Nudge Elastic Band (CI-NEB) method. Then by implementing the configurational dependent activation barrier into the KMC simulation, the lithium diffusivity will be studied. This atomistic simulation gives insight about the structural effects on lithium diffusivity in NMC to further develop this cathode material for high performance LIBs.

Изучение процесса ферментативного гидролиза предобработанной биомассы мискантуса

Forests being mostly non-renewable, miscanthus seems to be a promising alternative energy resource. This study investigates the enzymatic hydrolysis of pretreated miscanthus biomass. The research featured Miscanthus sinensis Strictus biomass. The methods included raw material pretreatment, enzymatic hydrolysis, matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF) of monosaccharide residues, and nuclear magnetic resonance (1H NMR) spectrometry of non-hydrolyzed lignin. A hammer mill with a particle size of 0.2–0.3 mm proved to be effective for preliminary mechanical processing of miscanthus. This type of treatment provided the maximal yield of carbohydrate-containing biomass (62.33 ± 1.87%). The optimal multi-enzyme composition included Cellulase Ultra obtained from Trichoderma reeseii, xylanase obtained from Thermomyces lanuginosus, and β-gluconase obtained from Myceliophtorafergusii. The fermentation temperature was 50 ± 1°C (72 ± 1 h). At these parameters, the conversion of holocellulose of miscanthus biomass was 96.0 ± 4.8%, and the yield of reducing substances was 97.00 ± 4.85%. The article introduces the optimal enzymatic hydrolysis parameters for pretreating Miscanthus sinensis Strictus biomass as a source of carbohydrate-containing substrates and describes their subsequent use for bacterial cellulose biosynthesis. The carbohydrate composition of hydrolysates included residual lignin, such polysaccharides as glucan and xylan, and various monosaccharides, namely arabinose, xylose, galactose, glucose, and uronic acids. Hydrolyzed miscanthus proved to be an effective renewable and environmentally friendly biodiesel.