Carbon Fuel Research Articles

Recent Progress in Electrochemical Upgrading of Bio-Oil Model Compounds and Bio-Oils to Renewable Fuels and Platform Chemicals.

Sustainable production of renewable carbon-based fuels and chemicals remains a necessary but immense challenge in the fight against climate change. Bio-oil derived from lignocellulosic biomass requires energy-intense upgrading to produce usable fuels or chemicals. Traditional upgrading methods such as hydrodeoxygenation (HDO) require high temperatures (200−400 °C) and 200 bar of external hydrogen. Electrochemical hydrogenation (ECH), on the other hand, operates at low temperatures (<80 °C), ambient pressure, and does not require an external hydrogen source. These environmental and economically favorable conditions make ECH a promising alternative to conventional thermochemical upgrading processes. ECH combines renewable electricity with biomass conversion and harnesses intermediately generated electricity to produce drop-in biofuels. This review aims to summarize recent studies on bio-oil upgrading using ECH focusing on the development of novel catalytic materials and factors impacting ECH efficiency and products. Here, electrode design, reaction temperature, applied overpotential, and electrolytes are analyzed for their impacts on overall ECH performance. We find that through careful reaction optimization and electrode design, ECH reactions can be tailored to be efficient and selective for the production of renewable fuels and chemicals. Preliminary economic and environmental assessments have shown that ECH can be viable alternative to convention upgrading technologies with the potential to reduce CO2 emissions by 3 times compared to thermochemical upgrading. While the field of electrochemical upgrading of bio-oil has additional challenges before commercialization, this review finds ECH a promising avenue to produce renewable carbon-based drop-in biofuels. Finally, based on the analyses presented in this review, directions for future research areas and optimization are suggested.

Pathways towards full use of hydrogen as reductant and fuel

The transition to a green steel making is a journey over decades that involves many technologies and pathways, in most scenarios with the use of hydrogen − both as reductant and as fuel − as the endgame. The paper describes a general pathway to decarbonisation including increased energy efficiency, use of low carbon fuels, carbon capture, and use of clean hydrogen as reductant and fuel. The possibilities for developing a greener blast furnace process as a short-term solution, is discussed. Combinations like direct reduced iron production with carbon capture using a gasified waste or biomass, could be a mid-term solution at some steel mills. Dependent on location-specific conditions some technologies, like use of hydrogen as fuel in reheating, is coming into use already now, whilst in other areas in near- and mid-term there will be intermediate solutions applied. Development of hydrogen production technologies is briefly described. Challenges for the transition are found not only within the steel industry itself, but also, e.g., in supply of renewable power and suitable iron ores. Moreover, potential supply chain integrations and impact of geographical dislocations are discussed. Overall, it is important to apply an integrated approach with clear milestones for the chosen pathway, where existing assets like blast furnaces are transformed into a lower carbon footprint operation applying technologies that also can be used in the subsequent transition, e.g., use of coke oven gas for producing direct reduced iron that is charged into blast furnaces where carbon capture is applied, or changing into more energy-efficient combustion systems that are ready for use of hydrogen when viably available.

Hydrogen Production and Applications: A review

A hydrogen fuel cell car, known as a Fuel Cell Electric Vehicle (FCEV), is essentially an electric vehicle that primarily relies on a fuel cell to generate energy. It also includes a secondary role for a battery within the powertrain. This technological configuration operates through four main scenarios, with the primary energy source being Hydrogen from onboard tanks, which powers the vehicle through the fuel cell and its associated components. Here's a breakdown of how it functions: Hydrogen enters the anode and interacts with a catalyst that separates hydrogen atoms, releasing electrons and protons. A conductive current collector connected to the vehicle's high-voltage circuitry collects these electrons. This electricity can charge the battery and/or drive the motors responsible for propelling the wheels. Fuel cells come in various types, characterized by the type of electrolyte they use, such as the Proton Exchange Membrane Fuel Cell (PEMFC), Solid Oxide Fuel Cell (SOFC), and Molten Carbonate Fuel Cell (MCFC). While all these fuel cell types can generate electricity, their efficiency can range from 30% to 60%. Although hydrogen fuel cell vehicles have shown promise, their adoption is still in its early stages due to challenges related to infrastructure, costs, and ongoing technological advancements. Our current research focuses on hydrogen production from renewable sources and its application in fuel cells to provide the required electrical power for electric vehicle propulsion. We aim to improve energy efficiency over a specified cycle and present a comprehensive analysis of our findings.

Financial Analysis of Innovative Wood Products and Carbon Finance to Support Forest Restoration in California

Abstract Traditional funding strategies of grants, congressional appropriations, and income from timber sales are insufficient to complete the level of forest restoration necessary throughout California. Stimulating investment into markets for low-value biomass—such as tops and branches of trees, small trees, and dead trees—will add value to forest raw materials and provide additional revenue streams to pay for forest restoration. We evaluate the investment potential of products made from low-value biomass using a discounted cash-flow analysis of several possible forest products including fuels and nonfuels under various climate policy and market scenarios. We demonstrate the carbon benefits provided by these products, attributed to their substitution for fossil-fuel feedstocks and long-term carbon storage. Our work finds that there is an opportunity to develop several highly profitable products, most notably fuels, many of which are eligible for energy and climate policy programs such as California's Low Carbon Fuel Standard and the federal Renewable Fuel Standard. Nonfuel products have an average internal rate of return (IRR) of 13 percent, whereas fuels have an average IRR of 19 percent in our baseline scenario. Although products ineligible for government incentives are generally less profitable, income from the voluntary carbon market greatly increases the IRR. Fostering investment into these products can encourage critically needed funding for forest management while developing a high-impact carbon removal solution enabled by state, federal, and voluntary climate initiatives. On this basis, we conclude that climate policy can support forest restoration in California.

ПЕРСПЕКТИВНЫЕ НАПРАВЛЕНИЯ ДЕКАРБОНИЗАЦИИ ПРОМЫШЛЕННОГО ПРОИЗВОДСТВА С ВЫСОКОЙ СОСТАВЛЯЮЩЕЙ УГЛЕРОДНОГО СЛЕДА В ВЫПУСКАЕМОЙ ПРОДУКЦИИ

The issue of decarbonization has remained the main one in the field of global ecology in recent years. The priority direction for reducing the carbon footprint is to increase the efficiency of electricity generation based on the combustion of carbon fuels, as well as the development of their own competencies in modern cogeneration technologies. The introduction of new restrictive measures in the field of reducing the environmental burden on the climate contribute to reducing the profitability of a number of industrial facilities without introducing the latest technologies for processing and capturing carbon dioxide generated during production.Carbon dioxide capture technologies currently cover, to one degree or another, all industrial areas related to carbon dioxide emissions, but are not sufficiently developed. Using carbon dioxide capture technologies, an important stage appears for its transportation to production or storage sites – using a gas pipeline or in a liquefied state, which is quite problematic and requires additional costs. Therefore, the article provides an overview of the most promising methods of recycling and outlines the vectors of their development

Techno-economic competitiveness of renewable fuel alternatives in the marine sector

The maritime sector accounts for almost 3% of global greenhouse gas emissions and is under increasing pressure to decarbonise rapidly. Renewable fuels represent a promising pathway for decarbonisation, but their high costs hinder adoption. Carbon Capture and Storage (CCS) can further augment marine fuel decarbonisation but adds to the cost. This work presents a harmonised cost comparison of four promising renewable carbon fuels (methanol, dimethyl ether (DME), liquefied natural gas (LNG) and bio-oil) produced either from routes utilising biomass (biofuels, including CCS) or CO2 (e-fuels). The differing technology status of the fuel production routes has been accounted for using the RAND Corporation method to estimate the cost of pioneer plants. Additionally, the impact of different levels of carbon taxation (15 or 140 €/t CO2) on the economic viability of the alternative fuels has been examined. None of the renewable fuels were found to be close to the incumbent fuels without carbon taxation, which needs to be considerable to adequately bridge the cost gap. Methanol and DME produced using point CO2 capture are the lowest cost choices if full scale sale of the oxygen by-product is considered. The biofuel routes remain at a premium to the existing fuels, while the direct air capture (DAC)-based fuels are the most expensive among the options studied, besides requiring completely renewable electricity for their carbon footprint to not exceed that of fossil fuels. Renewable LNG has a particularly high cost gap, bringing its status as a potential bridging fuel into doubt.

Hydrogen for Cooking: A Review of Cooking Technologies, Renewable Hydrogen Systems and Techno-Economics

About 3 billion people use conventional carbon-based fuels such as wood, charcoal, and animal dung for their daily cooking needs. Cooking with biomass causes deforestation and habitat loss, emissions of greenhouse gases, and smoke pollution that affects people’s health and well-being. Hydrogen can play a role in enabling clean and safe cooking by reducing household air pollution and reducing greenhouse gas emissions. This first-of-a-kind review study on cooking with hydrogen assessed existing cooking technologies and hydrogen systems in developing country contexts. Our critical assessment also included the modelling and experimental studies on hydrogen. Renewable hydrogen systems and their adoptability in developing countries were analysed. Finally, we presented a scenario for hydrogen production pathways in developing countries. Our findings indicated that hydrogen is attractive and can be safely used as a cooking fuel. However, radical and disruptive models are necessary to transform the traditional cooking landscape. There is a need to develop global south-based hydrogen models that emphasize adoptability and capture the challenges in developing countries. In addition, the techno-economic assumptions of the models vary significantly, leading to a wide-ranging levelized cost of electricity. This finding underscored the necessity to use comprehensive techno-economic assumptions that can accurately predict hydrogen costs.

Evaluating alternative low carbon fuel technologies using a stakeholder participation-based q-rung orthopair linguistic multi-criteria framework

It is widely believed that alternative low carbon fuels (ALCF) can be instrumental in achieving the transportation sector’s decarbonization goal. Unlike conventional fossil-based fuels, ALCF can be produced through a combination of different chemical processes and feedstocks. The inherent complexity of the problem justifies the multi-criteria decision-making (MCDM) approach to support decision-making in the presence of multiple criteria and data uncertainty. In this paper, we propose a novel stakeholder participation-based MCDM framework integrating experts' perspectives on ALCF production pathways using the analytics hierarchy process (AHP) and the q-rung orthopair linguistic partition Bonferroni mean (q-ROLPBM) operator. The key merit of our approach lies in treating criteria of different dimensions as heterogeneous indicators while considering the mutual influence between criteria within the same dimension. The proposed framework is applied to evaluate four ALCF production pathways against 13 criteria categorised under economic, environmental, technical, and social dimensions for the case of the United Kingdom (UK). Our analysis revealed the environmental and the economic dimensions to be the most important, followed by the social and technical evaluation dimensions. The e-fuel followed by the e-biofuel are found to be the two top-ranked production pathways that utilise the electrochemical reduction process and its combination with anaerobic digestion. These findings, along with our recommendations, provide decision-makers with guidelines on ALCF production pathway selection and formulate effective policies for investment.

Hydrogen production by using high-temperature gas-cooled reactors

Nuclear energy is a necessary component of a cheap and abundant total primary energy supply where there are no entries from the combustion of carbon and hydrocarbon fuels. This perspective discusses how high-temperature gas-cooled reactors could be developed targeting the production of electricity through advanced ultra-supercritical (AUSC) Rankine cycles and hydrogen through electrolysis (temperatures of the secondary heat transfer fluid <750 °C) as well as hydrogen through direct thermochemical cycles on top of AUSC electricity production (temperatures of the secondary heat transfer fluid 950 to 1000 °C).

Experiments and modeling to evaluate global reaction kinetics of three-way catalyst light off for net-zero carbon fuels and selected fuel blends

Internal combustion engine exhaust composition can have a significant impact on the light-off characteristics of CO, NO, and organics in the three-way-catalyst during cold-start. The U.S. Department of Energy’s Co-Optimization of Fuels and Engines initiative was aimed at developing new high-performance fuels, which raises the question of how current three-way-catalysts will perform if the exhaust composition is significantly changed. This work is aimed at quantifying the performance of the catalyst under a variety of different fuel components and mixtures. To this end, a reduced-order model is developed wherein the set of organics examined are placed into molecular groups based on their reactivities and to model each organic within that group with a common kinetic expression. This strategy allows for a first approximation to the light-off characteristics of all organics that fall within that group and to make predictions for fuel blends.

Thermoeconomic comparison of a molten carbonate fuel cell and a solid oxide fuel cell system coupled with a micro gas turbine as hybrid plants

This study presents a comparative evaluation of Molten Carbonate Fuel Cell (MCFC) and Solid Oxide Fuel cell (SOFC) stacks coupled with a micro gas turbine (MGT). For the analysis, it is assumed that the fuel supply to the stacks is constant in all the analyzed conditions. The components of the system have been sized using the first law of thermodynamics to meet the thermal conditions required to maintain fuel cell stack operation, while an exergetic analysis has been implemented in order to assess the components in terms of irreversibilities. Furthermore, an economic analysis to estimate the Levelized Cost of Electricity (LCOE) has been carried out to indicate the most feasible option between the two analyzed systems. The capacity of the fuel cell stacks is 500kWdc operating at 350 kPa and 600 °C/650 °C. The results indicate that MCFC stacks are more efficient than SOFC stacks, but are considerably more expensive. Nevertheless, the SOFC/MGT system has a global efficiency higher than that of the MCFC/MGT; also its Total Capital Investment (TCI) is 2.5–3.5 times lower, thus making the SOFC/MGT coupling more attractive. The only product considered coming out from the systems to determine the LCOE is electricity. The LCOE for the SOFC/MGT system is 0.339–0.402$/kWh and for the MCFC/MGT is 0.875–0.897$/kWh, which for both configurations is still higher than the current electricity prices. One aspect that increases the investment and consequently the LCOE is the high cost of the stacks and their replacements which is around 19 % and 10 % of the total Purchased Equipment Cost (PEC) for MCFC and SOFC stacks, respectively.

Investigation of ceria-molten carbonate electrolyte, composite anode and its catalytical effect on various carbon fuels in molten carbonate direct coal/carbon fuel cell

In order to improve the power density of molten carbonate direct coal/carbon fuel cell (MC-DCFC), a composite electrolyte of ceria-carbonate and ceria-coal/carbon anode are used. Electrochemical impedance spectroscopy (EIS) results reveal that ohmic resistance decreases 15–56.5 % in ceria-molten carbonate electrolyte. The surface morphology exhibit core–shell structures, which increase CO32− ionic transportation between the electrolyte surface and ceria-core particle. Among the all-carbon fuels, bituminous coal and graphite powders obtain a peak power density of 160 and 186 mW/cm2 with a maximum current density of 850 and 924 mA/cm2, respectively, at 700 ℃. In contrast, the catalytical effect of CeO2 (50 wt%) is analyzed on four different carbon fuels at 600 ℃. Incorporating ceria in graphite fuel lowers the apparent activation energy and enhances the reactivity. The EIS analysis displays the low charge transfer resistance in ceria-carbon fuel due to the indirect electrochemical redox. Ceria-graphite (≥100 µm) electrode achieves the highest power density of 203 mW/cm2 with a maximum current density of 1009 mA/cm2 for MC-DCFC at 600 ℃. In Ceria-graphite anode indirect redox pathway works together with direct electrochemical oxidation contributing to the high-power density, resulting in the maximum power density increase by 19.1 % compared to the carbonate electrolyte.

Direct carbon dioxide-methane solid oxide fuel cells integrated for high-efficiency power generation with La0.75Sr0.25Cr0.5Fe0.4Ni0.1O3–δ-based dry reforming catalyst

Solid oxide fuel cell (SOFC) can directly convert carbon-based fuels to power with low environmental impact and high energy efficiency, while there is still one of the key challenges that carbon deposition over Ni-based cermet anodes causes serious performance degradation. Herein, a Ni-doped perovskite, La0.75Sr0.25Cr0.5Fe0.4Ni0.1O3–δ (LSCFN), is prepared to design exsolution systems and evaluated as the dry reforming catalyst for direct carbon dioxide-methane SOFCs. It is demonstrated that the reducing atmosphere in anode effectively induce the NiFe alloy nanoparticles exsolution from LSCFN, and provide abundant active sites for dry reforming. Anode supported single cells with LSCFN-Ce0.9Gd0.1O2–δ (LSCFN-GDC) composite reforming catalyst show excellent electrochemical performance in both H2 and CH4-CO2, and the peak power densities of 686.05 and 684.83 mW·cm−2 are obtained at 800 ℃, respectively. The dry reforming of 50 %CH4-50 %CO2 integrated with LSCFN-GDC reforming catalyst is sustained for 100 h stable performance at 700 ℃ without any degradation, which are further confined by the experimental verification and thermodynamic calculation. These results demonstrate that additional dry reforming catalyst is an effective strategy to effectively manipulate CH4-CO2 reforming and electrochemical performance for energy purposes.

Towards feasible temperature management and thermo-mechanical stability of carbon-assisted solid oxide electrolysis cell

Carbon assisted solid oxide electrolysis cell (CA-SOEC) owns advantages of fast electrolysis rate, low operating cost and product flexibility. But the endothermic carbon gasification reaction leads to a steep temperature gradient in the anode, thus causing extra thermo-mechanical stress and inhibits long-term operation. Herein, we propose a new CA-SOEC using metal foam in the anode chamber and develop 2D numerical models to evaluate the fluid-dynamic/thermal/chemical/electrochemical/mechanical characteristics of the new cell. It is found that the use of metal foam can significantly enhance the heat transfer process and achieve an even temperature distribution in the CA-SOEC, where the peak temperature difference can be decreased from 57.0 to 21.5 K. As a result, the maximum thermo-mechanical stress is decreased by 69.9 % with the adoption of metal foam. Through further analyses of inlet gas flow rate, inlet gas temperature and the distance between anode chamber and electrode, we find that a small distance and a large flow rate are beneficial for optimizing the temperature distribution. The results of the study provide useful information for the structure optimization of solid oxide cells using carbon fuels.

Elucidating reaction pathways in CO2 electroreduction: Case study of Ag and Cu2O@Ag catalysts

CO2 electroreduction is a prospective avenue to produce carbon-based fuels, yet atomic-level insights on the mechanistic origin of catalytic selectivity remains elusive. Taking the Ag and Cu2O@Ag electrocatalysts as examples, Fourier-transform infrared spectroscopy in conjunction with theoretical calculations reveal that the hollow-nanostructured Ag promotes CO production through a lower energy barrier of the rate-limiting *CO2 to *COOH, while the Cu2O-Ag boundaries in the honeycomb-like Cu2O@Ag reinforce CO2 physisorption and chemisorption on the catalyst surface. The interfaces of Cu2O@Ag facilitate CO hydrogenation and CC coupling, opening alternative reaction pathways toward CH4 and C2H4. More broadly, this study provides insights to develop effective electrocatalysts in CO2 electroreduction and beyond.

Recent Advances and Future Perspectives of Metal-Based Electrocatalysts for Overall Electrochemical Water Splitting.

Recently, the growing demand for a renewable and sustainable fuel alternative is contingent on fuel cell technologies. Even though it is regarded as an environmentally sustainable method of generating fuel for immediate concerns, it must be enhanced to make it extraordinarily affordable, and environmentally sustainable. Hydrogen (H2 ) synthesis by electrochemical water splitting (ECWS) is considered one of the foremost potential prospective methods for renewable energy output and H2 society implementation. Existing massive H2 output is mostly reliant on the steaming reformation of carbon fuels that yield CO2 together with H2 and is a finite resource. ECWS is a viable, efficient, and contamination-free method for H2 evolution. Consequently, developing reliable and cost-effective technology for ECWS was a top priority for scientists around the globe. Utilizing renewable technologies to decrease total fuel utilization is crucial for H2 evolution. Capturing and transforming the fuel from the ambient through various renewable solutions for water splitting (WS) could effectively reduce the need for additional electricity. ECWS is among the foremost potential prospective methods for renewable energy output and the achievement of a H2 -based economy. For the overall water splitting (OWS), several transition-metal-based polyfunctional metal catalysts for both cathode and anode have been synthesized. Furthermore, the essential to the widespread adoption of such technology is the development of reduced-price, super functional electrocatalysts to substitute those, depending on metals. Many metal-premised electrocatalysts for both the anode and cathode have been designed for the WS process. The attributes of H2 and oxygen (O2 ) dynamics interactions on the electrodes of water electrolysis cells and the fundamental techniques for evaluating the achievement of electrocatalysts are outlined in this paper. Special emphasis is paid to their fabrication, electrocatalytic performance, durability, and measures for enhancing their efficiency. In addition, prospective ideas on metal-based WS electrocatalysts based on existing problems are presented. It is anticipated that this review will offer a straight direction toward the engineering and construction of novel polyfunctional electrocatalysts encompassing superior efficiency in a suitable WS technique.

Stabilization of Ru NPs over 3D LaCrO3 Nanostructures for High-Performance HER Catalysts in Acidic Media.

Hydrogen is considered as one of the best alternatives to carbon-based fossil fuels as energy sources. Electrocatalytic water splitting is one of the finest and eco-friendly methods for the production of hydrogen as compared to all other methods such as stream reforming carbon, hydrolysis of metal hydrides, etc. However, the sluggish kinetics on both the half-cell reactions limits the large-scale production of hydrogen. Hence, to overcome such kind of kinetic issues, designing a catalyst with characteristics of low overpotential and high stability is a matter of prime importance for the research community. Perovskite oxides are one of the well-documented materials for their excellent electrocatalytic water oxidation activity. But because of the lack of a proper proton adsorption site, these materials are unable to show proper hydrogen evolution reaction (HER) activity. Several strategies have been adopted for improving the HER activity of perovskite materials like cation doping, nanostructuring, etc. Here in this work, we prepared a shape-selective LaCrO3 (LCO) material. To enhance the electrocatalytic activity, we decorated the LCO with Ru nanoparticles via a hydrothermal method with different concentrations of Ru (Ru@LaCrO3), coined LCOn (n = 1-2.5). The as-synthesized RLCO2.5 showed the highest HER activity by demanding a low overpotential of 150 mV, whereas bare LCO demanded a higher overpotential of 364 mV to reach the benchmark current density of 10 mA/cm2. Also, RLCO2.5 showed a very low Rct value of 15.8 Ω and followed the facile kinetics with a lower Tafel value of 101 mV/dec. It also showed excellent stability over 55 h at a current density of 10 mA/cm2 in chronoamperometry studies. Acceleration degradation studies of RLCO2.5 showed comparably good activity with a small hike in overpotential toward HER. Hence, RLCO-based materials are highly helpful to develop efficient electrocatalysts to produce hydrogen in a large scale.

Biomass pyrolysis mechanism for carbon-based high-value products

The utilization of biomass, the only carbon-bearing renewable energy source, is critical for environmental and energy sustainability as well as carbon neutrality. Pyrolysis is the efficient conversion of biomass to fuel gas, liquid oil, and solid char. It is necessary to understand the mechanism of biomass pyrolysis for valuable and efficient utilization. In this review, recent progress with respect to biomass pyrolysis properties, the pyrolysis process, and product upgrading strategies focusing on carbon-based high-value liquid fuels and carbon-bearing materials are summarized. First, the correlations between the pyrolysis behavior and biomass structure and process conditions are considered. The mechanisms of the biomass pyrolysis of hemicellulose, cellulose, and lignin as well as the potential effect of inorganic matter on biomass pyrolysis are discussed. Furthermore, the regulation and controlling strategies for the biomass pyrolysis of high-value products are outlined. Finally, the challenges and prospects are discussed in order to provide a comprehensive picture of biomass pyrolysis development, which is significant for the understanding of biomass pyrolysis and the development of biomass utilization technology.

On factors of ions in seawater for CO2 reduction

Performing solar-driven CO2 reduction reaction (CO2RR) on the sea is desirable for future renewable energy landscape. However, CO2RR cannot be directly operated in natural seawater due to the unsuitable ionic environment. Herein, we studied CO2RR from the perspective of ions in seawater electrolyte on Copper. We find that multi-ions mixture in seawater could accelerate CO2RR by tuning electrode, local pH, and bulk electrolyte simultaneously. Specially, Na+_K+ mixture has a workable buffer capacity for regulating local pH and activating CO2 within electric-double-layer. Cl–_Br– mixture induces microstructural and actively changes on Cu electrode. While, in anions-mixture, SO42– would lower overpotential by reducing polarization loss in bulk electrolyte. Under this hierarchical structure of multi-ions in local environment, a well-performed CO2RR is achieved after optimizing ions-concentration and anode catalysts. Finally, by coupling a gas diffusion electrode with optimized seawater, the photovoltaic-driven electrolyzer obtained a 9.88 % solar-to-fuel efficiency (6.15 % solar-to- carbon-based fuels) under direct sunlight.

On the inner dynamics between Fossil fuels and the carbon market: a combination of seasonal-trend decomposition and multifractal cross-correlation analysis.

This study examines the inner dynamics of multifractality between the carbon market (EU ETS) and four major fossil fuel energy markets: Brent Crude Oil (BRN), Richards Bay Coal (RBC), UK Natural Gas (NGH2), and FTSE350 electricity index (FTSE350) from January 04, 2016, to March 04, 2022. First, we decompose the daily price changes by applying seasonal and trend decomposition using loess (STL). Then, we examine the inner dynamics of multifractality and cross-correlation by employing multifractal detrended fluctuation analysis (MFDFA) and multifractal detrended cross-correlation analysis (MFDCCA) using the remaining components of the return series. Our findings reveal that all series and the cross-correlations of carbon and fossil fuels markets have multifractal characteristics. We find crude oil to be the most efficient market (lowest multifractal), while coal is the least efficient (highest multifractal). Only coal shows persistent, whereas the other markets exhibit antipersistent behavior. Interestingly, the coal and EU ETS pair demonstrates a higher degree of multifractal patterns. In contrast, the pair of natural gas and EU ETS exhibits the lowest multifractal characteristics among the energy markets. Only the crude oil market shows persistent cross-correlations in the multifractality. These findings have important academic and managerial implications for investors and policymakers.