Energy & Fuels最新文献

{"title":"Review on Ammonia-Powered SOFCs: Fundamentals, Thermodynamics, Degradation Mechanisms, and Future Perspectives","authors":"Mian Muneeb Ur Rehman,&nbsp;Ali Muqaddas Mehdi,&nbsp;Wajahat Waheed Kazmi,&nbsp;Syed Ali Hassan Bukhari,&nbsp;Rizwan Javed,&nbsp;Hania Mumtaz,&nbsp;Faysal M. Al-Khulaifi,&nbsp;Amjad Hussain*,&nbsp;Muhammad Zubair Khan,&nbsp;Rizwan Raza*,&nbsp;Rak-Hyun Song* and Seung Won Lee*,&nbsp;","doi":"10.1021/acs.energyfuels.4c0615810.1021/acs.energyfuels.4c06158","DOIUrl":"https://doi.org/10.1021/acs.energyfuels.4c06158https://doi.org/10.1021/acs.energyfuels.4c06158","url":null,"abstract":"<p >Conventional technologies primarily powered by fossil fuels have led to significant environmental issues. Hydrogen, which is a carbon-free fuel, has emerged as a substantial energy sector in recent years. However, challenges related to its storage and long-distance transportation remain obstacles to its widespread use. Conversely, with its superior energy density (12.9 MJ L^–1) compared to hydrogen (5.6 MJ L^–1), ammonia is more amenable to transport and offers a CO₂-free alternative that is versatile enough for various power generation systems. In this context, solid oxide fuel cell (SOFC) technology stands out as an effective solution for directly converting ammonia into electrical energy with high efficiency. However, the progress of this technology is hampered by the sluggish kinetics of the chemical and electrochemical processes occurring at the anodes and catalysts, limiting its commercialization. This review covers the fundamental principles, thermodynamics, and kinetics of the ammonia dissociation reaction, offering a comprehensive overview of how these factors influence the electrochemical performance and long-term durability of direct ammonia fuel cells at both the single-cell and stack levels. Furthermore, it provides critical insights for improving performance and mechanistic understanding while establishing a conceptual framework for the design of electrodes for ammonia-powered SOFC.</p>","PeriodicalId":35,"journal":{"name":"Energy & Fuels","volume":"39 13","pages":"6097–6117 6097–6117"},"PeriodicalIF":5.2,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143758806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Water Oxidation Catalysis by an Iridium Complex Stabilized with an N,N,O-Donor Tripodal Ligand","authors":"Giulia Luciani,&nbsp;Cristina Decavoli,&nbsp;Robert H. Crabtree and Gary W. Brudvig*,&nbsp;","doi":"10.1021/acs.energyfuels.5c0057810.1021/acs.energyfuels.5c00578","DOIUrl":"https://doi.org/10.1021/acs.energyfuels.5c00578https://doi.org/10.1021/acs.energyfuels.5c00578","url":null,"abstract":"<p >The facial tridentate N,N,O-donor ligand bpeH [1,1-di(pyridin-2-yl)ethanoate, <b>L2</b>] is based on the successful pyalkH [2-(2′-pyridyl)-2-propanoate, <b>L1</b>] ligand. <b>L1</b> yields a precatalyst [Cp*Ir(pyalk)Cl] (<b>1</b>) that we have used extensively for water oxidation catalysis. We now find that <b>L2</b> readily forms an Ir(III) water oxidation precatalyst, [Cp*Ir(bpe)]Cl (<b>2</b>) that can subsequently be chemically activated with sodium periodate to form a novel Ir(IV) water oxidation catalyst in the form of a blue solution species (<b>BS2</b>) analogous to the blue solution species (<b>BS1</b>) formed from <b>1</b>. By optimizing the NaIO₄ stoichiometry in the activation process, a O₂ yield for water oxidation of 84% was achieved. A comparison of the activation of <b>1</b> and <b>2</b> showed that <b>2</b> yields a water oxidation catalyst with a higher O₂ yield. However, <b>BS2</b> exhibited a 10-fold lower turnover frequency and reaction rate compared to <b>BS1</b>, likely because water molecules cannot access the positions trans to the μ-oxo ligand. This limitation causes <b>BS2</b> to evolve into a more stable but less catalytically active molecular configuration. After O₂ evolution following the addition of NaIO₄ has ceased, <b>BS2</b> reaches a quiescent state able to maintain its molecular integrity such that it can be reactivated with periodate even after 10 days under ambient conditions, restoring approximately 80% of the initial O₂ yield. Notably, minimal periodate addition was sufficient to reactivate the catalytic species. <b>L2</b> further allowed the acquisition of the first clearly identifiable ¹H NMR spectrum of a blue solution. While the formation of paramagnetic species complicated complete NMR spectroscopic characterization, ongoing efforts are focused on elucidating the molecular structure of both the active and dormant species.</p>","PeriodicalId":35,"journal":{"name":"Energy & Fuels","volume":"39 13","pages":"6549–6558 6549–6558"},"PeriodicalIF":5.2,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143758842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unlocking the Electrocatalytic Potential of Sb2Se3 for HER via Cu Doping-Induced Phase Conversion and rGO Integration","authors":"Shah Jahan Ul Islam,&nbsp;Muzaffar A. Bhat,&nbsp;Afshana Hassan,&nbsp;Amir Hussain Wani,&nbsp;Manzoor Ahmad Dar*,&nbsp;Kowsar Majid* and Malik Wahid*,&nbsp;","doi":"10.1021/acs.energyfuels.4c0611910.1021/acs.energyfuels.4c06119","DOIUrl":"https://doi.org/10.1021/acs.energyfuels.4c06119https://doi.org/10.1021/acs.energyfuels.4c06119","url":null,"abstract":"<p >In this study, we explore the electrocatalytic hydrogen evolution reaction (HER) performance of Cu-doped Sb₂Se₃ anchored to reduced graphene oxide (rGO). Although pristine Sb₂Se₃ is typically inactive for HER, its activity is significantly enhanced through Cu doping and integration with rGO, achieved via a one-step hydrothermal process. The resulting CuSbSe₂-rGO catalyst benefits from the synergistic interaction between rGO and Cu, exhibiting superior HER activity compared with control samples: Sb₂Se₃, Sb₂Se₃-rGO, and CuSbSe₂. The electrochemical characterization demonstrates that rGO incorporation enhances stability, conductivity, and surface area. The optimized CuSbSe₂-rGO catalyst shows enhanced HER performance, with an onset potential of 293 mV, an overpotential of 386 mV at a current density of 10 mA cm^–2, and a Tafel slope of 158 mV dec^–1. The catalyst’s superhydrophilic surface (contact angle &lt;5°) promotes efficient wetting and ion diffusion, further improving HER efficiency. Density functional theory calculations indicate that Cu doping reduces the band gap of Sb₂Se₃ from 1.31 to 1.16 eV due to the distribution of Cu states near the Fermi level, a modification that likely contributes to the observed reduction in the overpotential requirements. These findings highlight the potential of CuSbSe₂-rGO for the advancement of water electrolysis technologies.</p>","PeriodicalId":35,"journal":{"name":"Energy & Fuels","volume":"39 14","pages":"6957–6967 6957–6967"},"PeriodicalIF":5.2,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143806727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Model Optimization and Data Analysis Methods for Low-Temperature CO2 and N2 Adsorption Experiments on Carbonaceous Materials","authors":"Ziyi Wang,&nbsp;Dangyu Song*,&nbsp;Yunbo Li*,&nbsp;Yingquan Zhai,&nbsp;Jienan Pan,&nbsp;Xiaowei Shi and Guoqin Wei,&nbsp;","doi":"10.1021/acs.energyfuels.5c0014210.1021/acs.energyfuels.5c00142","DOIUrl":"https://doi.org/10.1021/acs.energyfuels.5c00142https://doi.org/10.1021/acs.energyfuels.5c00142","url":null,"abstract":"<p >Low-temperature gas adsorption experiments are widely utilized to evaluate the pore structures of porous materials. Understanding the applicability of each model in different types of samples is crucial, as these models can yield diverse interpretations of pore structures from identical experimental data. In this study, low-temperature CO₂/N₂ isothermal adsorption experiments were conducted on coal, shale, and activated carbon samples to compare and analyze the suitability of each model in different samples and pore size ranges. The key findings are as follows. (1) Low-temperature CO₂/N₂ adsorption experiments provide insight into pore volume, specific surface area, and pore size distribution ranging from 0.36 to 160 nm in coal, shale, and activated carbon pores. (2) The CO₂-DFT model is applicable for analyzing the low-temperature CO₂ adsorption experiments in all samples. For the analysis of pores smaller than 35 nm in the low-temperature N₂ adsorption experiment, the slit hole nonlocal density functional theory model is recommended for middle-rank coal and the slit/cylindrical Quench Solid Density Functional Theory adsorption branch model for high-rank coal, shale, and activated carbon samples. For pore size larger than 35 nm, the Barrett–Joyner–Halenda model is recommended to analyzing the adsorption branches. (3) For overlapping pore interval of the different model’s analysis results, the CO₂-DFT model is recommended for the range of 1.41–1.47 nm, and the N₂-DFT model is recommended for the range of 4.14–36.00 nm.</p>","PeriodicalId":35,"journal":{"name":"Energy & Fuels","volume":"39 13","pages":"6300–6309 6300–6309"},"PeriodicalIF":5.2,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143758793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tetra-n-butylammonium Tricarboxylate Semiclathrate Hydrates as Phase Change Materials: Phase Equilibrium Relations and Memory Effect in Reformation","authors":"Kazuhiro Minamikawa,&nbsp;Jin Shimada,&nbsp;Takeshi Sugahara* and Takayuki Hirai,&nbsp;","doi":"10.1021/acs.energyfuels.5c0050210.1021/acs.energyfuels.5c00502","DOIUrl":"https://doi.org/10.1021/acs.energyfuels.5c00502https://doi.org/10.1021/acs.energyfuels.5c00502","url":null,"abstract":"<p >Semiclathrate hydrates (SCHs), one of the phase change materials for cold energy storage, are crystalline compounds consisting of host water molecules and appropriate guest substances. The typical guest substances of SCHs are tetra-<i>n</i>-butylammonium (TBA) salts. In the present study, we investigated the phase equilibrium relations of (TBA)₃ tricarboxylate SCHs, where citrate (−Cit) and 1,2,3-propanetricarboxylate (−123Pro) were used as environmentally friendly tricarboxylate anions. The maximum equilibrium temperatures of (TBA)₃-Cit and (TBA)₃-123Pro SCHs, whose phase diagrams exhibited a congruent-type phase behavior, were 286.02 ± 0.05 and 286.34 ± 0.05 K, respectively. Their dissociation enthalpies were 186 ± 3 and 193 ± 3 kJ/kg, respectively, which are as large as that of TBA-bromide SCH that has been put to practical use in cold energy storage applications. As an index for suppressing the degree of supercooling in SCH reformation, we have focused on the memory effect. The ability to retain the memory effect in the (TBA)₃-Cit and (TBA)₃-123Pro SCHs was relatively large. The (TBA)₃-Cit and (TBA)₃-123Pro SCHs would be superior phase change materials for cold energy storage.</p>","PeriodicalId":35,"journal":{"name":"Energy & Fuels","volume":"39 14","pages":"7104–7109 7104–7109"},"PeriodicalIF":5.2,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143806627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correlation between Pore Characteristics and High-Performance Carbon Dioxide Capture of Sustainable Porous Carbon Derived from Kraft Lignin and Potassium Carbonate","authors":"Khoa Anh Le Cao,&nbsp;Kiet Le Anh Cao*,&nbsp;Oktaviardi Bityasmawan Abdillah,&nbsp;Eka Lutfi Septiani,&nbsp;Tomoyuki Hirano,&nbsp;Nhan Trung Nguyen and Takashi Ogi*,&nbsp;","doi":"10.1021/acs.energyfuels.5c0012510.1021/acs.energyfuels.5c00125","DOIUrl":"https://doi.org/10.1021/acs.energyfuels.5c00125https://doi.org/10.1021/acs.energyfuels.5c00125","url":null,"abstract":"<p >The development of cost-effective and efficient adsorbents for CO₂ capture has gained significant interest, with biomass-derived porous carbon materials emerging as promising candidates due to their outstanding textural properties, tunable porosity, and low production cost. This study introduces for the first time a sustainable fabrication of porous carbon from Kraft lignin using K₂CO₃ as an environment-friendly activator via a spray drying approach and carbonization process. K₂CO₃ offers a low-toxic, low-corrosive, and eco-friendly alternative to KOH, making it safer for long-term equipment use and more suitable for large-scale applications. Furthermore, K₂CO₃ effectively creates a microporous structure for CO₂ adsorption while simplifying waste management due to its benign and recyclable carbonate residues. Unlike conventional two-step activation, our approach integrates carbonization and activation into a single step, reducing production time and enhancing efficiency, making it suitable for practical applications. Porous carbon materials obtained through this novel process exhibited a CO₂ adsorption capacity of 4.54 mmol/g at 298 K, comparable to those activated with KOH and outperforming many previously reported adsorbents. Additionally, the effects of K₂CO₃ concentration and carbonization temperature were systematically studied to optimize CO₂ adsorption performance. A linear correlation analysis between pore structure parameters and CO₂ captures highlighted ultramicropores as key contributors to adsorption efficiency.</p>","PeriodicalId":35,"journal":{"name":"Energy & Fuels","volume":"39 13","pages":"6372–6387 6372–6387"},"PeriodicalIF":5.2,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143758933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"THF-CH4 Hydrate Formation under Static Conditions with the Change of Temperature: Application to CH4 Storage in the Form of Gas Hydrates","authors":"Bin-Bin Ge,&nbsp;Dong-Liang Zhong*,&nbsp;Yi-Yu Lu* and Ruo-Gu Kuang,&nbsp;","doi":"10.1021/acs.energyfuels.5c0050110.1021/acs.energyfuels.5c00501","DOIUrl":"https://doi.org/10.1021/acs.energyfuels.5c00501https://doi.org/10.1021/acs.energyfuels.5c00501","url":null,"abstract":"<p >The hydrate-based solidified natural gas technology offers a promising approach to the storage and transportation of natural gas. A key challenge of this technology is to achieve mild hydrate formation conditions and high gas storage capacity. In this work, the effects of temperature on THF-CH₄ hydrate formation under static conditions were investigated from multiple perspectives including kinetic measurement, thermal analysis, morphology observation, and in situ Raman spectroscopy. Moreover, the storage stability of THF-CH₄ hydrate above the freezing point was explored. The results indicate that 288.15 K is a preferable temperature for increasing the gas uptake of THF-CH₄ hydrate formation among the tested temperatures (280.15, 288.15, and 293.15 K), and the highest gas uptake of 0.0756 mol of gas/mol of water was achieved. The continued growth of cloud-like hydrates in the liquid phase was observed, which enhances CH₄ diffusion for further hydrate growth. In situ Raman spectroscopy measurement revealed a two-stage growth mechanism in the formation of THF-CH₄ hydrate. THF-CH₄ hydrate can be stably stored at atmospheric pressure and 277.15 K, with only a 3% gas evolution from the hydrate. The results presented in this work will provide valuable insights for improving the solidified natural gas storage and transportation technology.</p>","PeriodicalId":35,"journal":{"name":"Energy & Fuels","volume":"39 13","pages":"6232–6240 6232–6240"},"PeriodicalIF":5.2,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143758929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface Tension Prediction of Fuel Additives Based on Machine Learning Model with Subtraction-Average-Based Optimizer Algorithm","authors":"Jianan Wang,&nbsp;Qing Duan,&nbsp;Xuyao Tang and Shengshan Bi*,&nbsp;","doi":"10.1021/acs.energyfuels.4c0640410.1021/acs.energyfuels.4c06404","DOIUrl":"https://doi.org/10.1021/acs.energyfuels.4c06404https://doi.org/10.1021/acs.energyfuels.4c06404","url":null,"abstract":"<p >Fuel additives play a significant role in improving combustion efficiency and fuel quality, with their surface tension being a crucial thermophysical property that directly affects atomization and cylinder performance. To address the demand for thermophysical data of fuel additives, 574 surface tension data for 22 fuel additives were extensively collected and evaluated using empirical models. A modified Sastri-Rao model (M-Sastri-Rao model) was built with critical temperature (<i>T</i>_c), reduced temperature (<i>T</i>_r), critical pressure (<i>p</i>_c), boiling point temperature (<i>T</i>_b), and acentric factor (ω) as influencing factors. The empirical models were found to have limited accuracy in predicting the surface tension. Then, a BP neural network model with the subtraction-average-based optimizer (SABO) algorithm was proposed. The results show that the SABO-BP model significantly reduced the deviation between calculated and experimental values, outperforming the previous empirical models. Various evaluation metrics were calculated for the SABO-BP model. The distribution of Bias ranged within ±5%, and the mean absolute error reached 0.165 mN·m^–1. The key parameters affecting the model were identified through a SHAP interpretability analysis. The SABO-BP model can accurately provide surface tension data for applications in the design and simulation.</p>","PeriodicalId":35,"journal":{"name":"Energy & Fuels","volume":"39 13","pages":"6195–6207 6195–6207"},"PeriodicalIF":5.2,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143758934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ZTE Imaging for High-Resolution Characterization of the Shale Pore Structure and Fluid Distribution","authors":"Zhenshuo Ma,&nbsp;Yan Zhang* and Lizhi Xiao,&nbsp;","doi":"10.1021/acs.energyfuels.5c0018910.1021/acs.energyfuels.5c00189","DOIUrl":"https://doi.org/10.1021/acs.energyfuels.5c00189https://doi.org/10.1021/acs.energyfuels.5c00189","url":null,"abstract":"<p >Shale oil is mainly stored in the pores and cracks of mud shale reservoirs, which is the mainstream oil and gas resource development in the world today. Shale is a complex porous medium with low porosity and low permeability, which results in a short relaxation time of the nuclear magnetic resonance (NMR) signal. By characterizing the pore structure and fluid distribution of shale, one can effectively guide the exploration of shale oil. However, the NMR relaxation signal of shale decays so rapidly that it cannot be effectively characterized by conventional magnetic resonance imaging (MRI) methods. Zero echo time imaging (ZTE) is often used for imaging short <i>T</i>₂ tissues under high field conditions, where the theoretical value of the echo time (TE) of the pulse sequence is zero. In this study, the ZTE technique is implemented under low-field NMR, and the ZTE sequence is combined with relaxation NMR to obtain local information for shale samples before and after fluid self-absorption. The results show that ZTE technology can be applied to obtain high-quality shale images, and the heterogeneity of these samples was characterized. The fluid signals inside the samples were monitored, and the pore structure and fluid distribution inside the shale were characterized on macroscopic and microscopic scales. This method provides a trustworthy experimental technique for shale characterization and will benefit the oil industry.</p>","PeriodicalId":35,"journal":{"name":"Energy & Fuels","volume":"39 13","pages":"6208–6219 6208–6219"},"PeriodicalIF":5.2,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143758914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Combustion and Emission Characteristics of an Ammonia–Diesel Dual-Fuel Engine under High Ammonia Substitution Ratios","authors":"Shouzhen Zhang,&nbsp;Rui Yang,&nbsp;Qinglong Tang*,&nbsp;Zhijie Lv,&nbsp;Haifeng Liu,&nbsp;Zongyu Yue and Mingfa Yao,&nbsp;","doi":"10.1021/acs.energyfuels.5c0021410.1021/acs.energyfuels.5c00214","DOIUrl":"https://doi.org/10.1021/acs.energyfuels.5c00214https://doi.org/10.1021/acs.energyfuels.5c00214","url":null,"abstract":"<p >To assess the potential for reducing carbon emissions, this study investigated the effects of fuel injection strategies, intake conditions, and engine speeds on combustion performance in ammonia–diesel dual-fuel engines. The results indicate that a high diesel injection pressure combined with advanced injection timing enhances the premixing of diesel and ammonia, shortens the ignition delay, and accelerates the combustion process, thereby improving the indicated thermal efficiency (ITE). Increasing the equivalence ratio reduces the compression pressure and temperature while decreasing the oxygen concentration around the diesel spray. This results in a longer ignition delay, a delayed combustion phase, and a combustion duration that initially shortens and then extends. Consequently, the ammonia combustion efficiency initially increases rapidly before gradually declining, while the ITE exhibits a similar trend, first increasing and then decreasing. At an ammonia energy fraction of 70%, the maximum ITE reaches 50.3%, representing an improvement of 6.7% compared with the pure diesel mode. At this point, the ammonia combustion efficiency is 94.6%, with NH₃ emissions of 14.5 g/kW·h, N₂O emissions of 0.17 g/kW·h, and NOx emissions of 2.9 times higher than the pure diesel mode. However, greenhouse gas (GHG) emissions are reduced by 67.5% compared with the pure diesel mode. Lower engine speeds of 1000 rpm result in lower greenhouse gas (GHG) emissions and ITE than 1500 rpm. Ammonia-fueled engines show promise in enhancing ITE and mitigating GHG emissions.</p>","PeriodicalId":35,"journal":{"name":"Energy & Fuels","volume":"39 13","pages":"6559–6571 6559–6571"},"PeriodicalIF":5.2,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143758887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}