Energies
·
2022
·Vol. 15
·期 3
·1023
·
IF 3.252
Xiaowei Xu,Enlong Liu,Neng Zhu,Fanfu Liu,Feng Qian
As fossil fuels continue to be extracted and used, issues such as environmental pollution and energy scarcity are surfacing. For the transportation industry, the best way to achieve the goal of “carbon neutrality” is to research efficient power systems and develop new alternative fuels. As the world’s largest product of chemicals, ammonia is a new renewable fuel with good combustion energy. It can be used as an alternative fuel to reduce carbon emissions because of its proven production process, low production and transportation costs, safe storage, the absence of carbon-containing compounds in its emissions, and its future recyclability. This paper firstly introduces the characteristics of ammonia fuel engine and its problems; then it summarizes the effects of various ammonia-blended fuels on the combustion and emission characteristics of the engine from the combustion problem of ammonia-blended engine; then the fuel storage of ammonia-blended hydrogen is discussed, the feasibility of hydrogen production instead of hydrogen storage is introduced.Keywords:engine;mixed fuel;hybrid fuel;combustion performance;emissions
研究领域:
能源工程
·
环境科学
✓ 已验证
DOI
高影响因子
Sustainable Energy & Fuels
·
2025
·
IF 4.1
Zilan Jiang,Sibin Zhu,Xufeng Tang,Haibo Tang,Xiaoming Zhu,Lun Yu,Letian Li,Yadong Wang,Haolin Tang,Xiaoling Liu
Owing to their high theoretical energy density and carbon-free operation, Direct Ammonia Fuel Cells (DAFCs) have recently garnered substantial interest in the research community. However, the sluggish kinetics of the Ammonia Oxidation Reaction (AOR) significantly limit the practical applications of DAFCs. The ternary alloy catalyst PtIrZn has become a research focus due to its excellent electrocatalytic performance. However, designing PtIrZn nanocubes with high (100)-facet exposure to maximize AOR performance remains a major challenge. In this study, high (100)-facet-exposed PtIrZn nanocubes were successfully synthesized using a hydrothermal method, employing oleylamine as a reducing agent and dibenzyl ether as a morphology-directing agent. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) characterization confirmed their cubic structure and high proportion of (100) facets. Electrochemical testing indicated that PtIrZn nanocubes exhibited a significant current density (163.94 A g-1PtIr) in AOR, outperforming previously reported PtIrZn catalysts. Density Functional Theory (DFT) calculations further revealed that the (100) facets in the as-designed PtIrZn possess a lower reaction energy barrier and a more negative d-band center compared to the (111) facets. This leads to an enhanced dehydrogenation capacity of NH₃ and consequently accelerates the rate of AOR.
研究领域:
材料科学
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电化学
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催化科学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Bangze Wu,Xiaole Yu,Zenan Zhao,Bingyu He,Zhanheng Jin,Zhexiang Yu,Qing Ni,Shoucheng He,Han Chen,Yifeng Zheng,Sheng Cui,Lin Ge
Ammonia-fueled protonic ceramic fuel cells (PCFCs) are emerging as promising alternatives to H 2 -fueled PCFCs, offering advantages such as higher energy density and enhanced safety. However, their widespread application is impeded by challenges, including insufficient catalytic activity towards ammonia and limited stability of the anode structure. Herein, we report a rational design for Ni 97 Co 3 -BaCe 0.7 Zr 0.1 Y 0.1 Yb 0.1 O 3− δ (BCZYYb) cermet anodes, aimed at enhancing both catalytic activity and durability for ammonia utilization. The cell featuring the Ni 97 Co 3 -BCZYYb anode leverage the synergistic interaction between Ni and Co to enhance ammonia adsorption and nitrogen desorption, resulting in a remarkable 67.8 % increase in power density when operating with NH 3 at 600 °C. Notably, upon switching the fuel from H 2 to NH 3 , this achieves an unprecedented power retention of 87.2 % at 700 °C, representing one of the highest values recorded for ammonia-fueled PCFCs, while most ammonia-fueled cells exhibit power retention in the range of only 60–80 %. Furthermore, the cell with Ni 97 Co 3 -BCZYYb cermet anode demonstrates exceptional durability, stable operation over 30 h at 650 °C under NH 3 with no degradation observed. This longevity is attributed to the excellent sintering resistance of the NiCo alloy, highlighting the potential of the Ni 97 Co 3 -BCZYYb cermet anode for long-term applications. This work provides an effective strategy for designing highly active and durable anodes for ammonia-fueled PCFCs.
研究领域:
材料科学
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能源技术
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2025
·
IF 9
Zhilin Jiao,Yun Zhao,Yangkai Han,Zhiwei Ren,Jingshuai Yang,Zhigang Shao
Ammonia crossover in hydroxide exchange membrane (HEM) poses a significant challenge to the advancement of low-temperature DAFCs. In this study, we have developed two types of macromolecule crosslinked HEMs (PNH-ene-x and PNH-yne-x) through a straightforward in-situ thermal crosslinking method using alkenes and aromatic crosslinked moieties. The engineered crosslinked networks demonstrate dual functionality: effectively limiting water absorption to suppress ammonia permeation (2.62 × 10 −7 cm 2 s −1 for PNH-ene-2%) while maintaining a well-defined microphase-separated morphology to promote hydroxide ion conduction (45.1 mS cm −1 at 30 °C). PNH-ene-2% achieves a superior membrane selectivity (9.57 × 10 7 mS s cm −3 ) through optimal balance between transport properties and structural stability. Accordingly, the DAFC with PNH-ene-2% exhibits a high cell energy efficiency (26.9%) and a modest peak power density (256.8 mW cm −2 ), representing the best record for low-temperature DAFCs to date. This work suggests that crosslinking is an effective approach to prepare high-performance HEMs for low-temperature DAFCs.
研究领域:
材料科学
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能源技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
·
IF 8.4
Yangkai Han,Yun Zhao,Zhiwei Ren,Tao Wei,Haitao Zhang,Shucheng Sun,Hongmei Yu,Zhigang Shao
Low-temperature direct ammonia fuel cells (DAFCs) have attracted widespread attention due to carbon-neutral property, high volumetric energy density, and low source-to-tank costs of ammonia. However, high ammonia crossover which leads to poor cell energy efficiency, is a big challenge for DAFCs. Ammonia crossover is dominantly related to hydroxide exchange membranes (HEMs), and the deep understanding of ammonia crossover behavior in HEMs is lacking in this field. Herein, we have elaborately investigated physical characterizations of different poly (aryl piperidinium)-based HEMs and find that the ammonia permeability is exponentially inversely proportional to the reciprocal of water volume fraction for HEMs. We have also evaluated the energy efficiency of DAFCs with different HEMs by combining two factors of ammonia crossover and cell performance. The DAFC based on the TP-100-QC6 with low ammonia crossover and modest ionic conductivity can achieve a high cell energy efficiency of 33 %, which is much higher than DAFC (14 %) with a benchmark HEM of TP-100. This work suggests that pursuing highly conductive HEMs simultaneously with low water volume fraction to lower ammonia crossover is of vital importance for the future development of DAFCs.
研究领域:
能源科学
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yanchen Lai,Bowen Wang,Bingfeng Zu,Chasen Tongsh,Zhengguo Qin,Qing Du,Shangfeng Jiang,Kui Jiao
Clarifying the mass transfer mechanism of direct ammonia fuel cell (DAFC) can provide theoretical support for solving its complex water and heat management problems. Electrochemical impedance spectroscopy (EIS) as an electrochemical measurement technique that can characterize the losses in various parts of an electrochemical system, but it’s rarely used in DAFC experimental research. Therefore, this study proposes an EIS equivalent circuit model for low-temperature DAFC, which is used to quantitatively characterize the Faradaic impedance, Ohmic impedance, and mass transfer impedance of cells, meanwhile, the model takes into account the influence of solution aggregation in the anode diffusion layer (ADL). This study prepares 3 ADLs with different water contact angles and explores the influence of ADL hydrophobicity on DAFC performance through fitting between equivalent circuit model and experimental results. We find that DAFC with moderately hydrophobicity ADL which water contact angle of 126.5° exhibits better electrochemical performance, with peak power density of 10.07 mW cm −2 . As hydrophobicity decreases, water contact angle reduces to 100.9°, the solution aggregation phenomenon occurring at ADL becomes severe, which in turn increases the Ohmic impedance of 160 mΩ cm 2 and reduces cell performance. The cell with ADL water contact angle of 142.7° doesn’t exhibit solution aggregation in diffusion layer, its Ohmic impedance reduces by 270 mΩ cm 2 compare to the cell with ADL water contact angle of 126.5°, but its performance decrease to 9.23 mW cm −2 due to insufficient reactant supply. This study also explores the influence of ADL hydrophobicity on DAFC output stability. This achievement can enrich the theory of DAFC testing and to some extent fill the gap in the study of DAFC mass transfer mechanism.
研究领域:
能源科学
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电化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Zhenzhong Liu,Yi Li,Xiangsong Zhang,Shaosheng Rao,Jinghan Li,Wenlong Wang,Zhongti Sun,Juan Yang
Achieving high catalytic ammonia oxidation reaction (AOR) performance of Pt-based catalysts is of paramount significance for the development of direct ammonia fuel cells (DAFCs). However, the high energy barrier of dehydrogenation of *NH2 to *NH and easy deactivation by *N on the Pt surface make the AOR show sluggish kinetics. Here, we have put forward an alloying and surface modulation tactic to optimize Pt catalysts. Several spherical PtM (M = Co, Ni, Cu, and Pd) binary nanoparticles were controllably loaded on reduced graphene oxide (rGO). Among others, spherical PtPd nanoparticles displayed the most efficient catalytic activity. Further surface engineering of PtPd nanoparticles with a cubic-dominant structure has resulted in dramatic AOR activity improvements. The optimized (100)Pt85Pd15/rGO exhibited a low onset potential (0.467 V vs reversible hydrogen electrode (RHE)) and high peak mass activity (164.9 A g–1), much better than commercial Pt/C. Nevertheless, a short-term stability test along with morphology, structure, and composition characterizations indicate that the leaching of Pd atoms from PtPd alloy nanoparticles, their structure transformations, and the possible poisoning effects by the N-containing intermediates could result in the catalyst’s activity loss during the AOR electrocatalysis. A temperature-dependent electrochemical test confirmed a reduced activation energy (∼12 kJ mol–1 decrease) of cubic-dominant PtPd compared to Pt/C. Density functional theory calculations further demonstrated that Pd atoms in Pt decrease the reaction energy barrier of electrochemical dehydrogenation of *NH2 to *NH, resulting in an excellent catalytic activity for the AOR.
研究领域:
材料科学
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电化学
·
催化反应
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED ENERGY
·
2025
·
IF 11
Xianda Sun,Baibin Ma,Jinxu Hao,Zirui Wu,Yi Li,Hao Liu,Yuandong Yang,Xiaohan Ren
The ammonia crossover that poisons the conventional cathode catalysts and damages the cell performance and efficiency is one of the paramount bottlenecks limiting the development of direct ammonia fuel cells (DAFCs). Synthetizing the ammonia tolerance catalysts has been proven to be an effective avenue to solve the above-mentioned problems, however, the mass and charge transports within the anti-ammonia poisoning electrodes has not been fully elucidated. Herein, an alkaline DAFC with anti-ammonia poisoning Fe-N-C cathode is reported, and the main effort is expended on investigating the impact of mass and charge transports on cell performance, internal resistance, and operating stability. The alkaline DAFC exhibits a thermodynamic efficiency as high as 88.6 %, higher than that of hydrogen-based fuel cells. The preliminary experimental results indicate that the performance of DAFC with anti-ammonia poisoning Fe-N-C cathode is higher than that of conventional Pt/C cathode under the same catalyst loading. The impressive open-circuit voltage of 0.74 V and peak power density of 107 mW cm −2 are obtained under atmospheric pressure and 80 °C, which is primarily ascribed to both the anti-ammonia poisoning of Fe-N-C catalyst and the facilitated mass and charge transports. Furthermore, the voltage curve of DAFC is quite stable during the constant-current discharging at 100 mA cm −2 for 10-h, demonstrating the good durability of DAFC with anti-ammonia poisoning Fe-N-C cathode.
研究领域:
电化学
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能源材料
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催化化学
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燃料电池
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界面传输
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry Letters
·
2025
·
IF 4.6
Weidong Tang,Xiaohui Xu,Yu Cheng,Baocong Guo,Xinnan Xu,Chunlin Mu,Yinshi Huang,Xi Zhou,Chenglin Yan,Tao Qian
The efficient development of electrocatalysts for ammonia oxidation anodes represents a critical challenge which hinders the commercialization of direct ammonia fuel cells (DAFCs) and the realization of energy transition goals. Platinum (Pt)-based catalysts play a key role in ammonia oxidation reactions (AOR); however, their reaction kinetics are sluggish at low temperatures and are susceptible to toxicity from intermediate species such as *N, which limits their applicability at ampere-level currents. Drawing inspiration from the “stepwise dehydrogenation mechanism” and the concept of “Bader charge”, we have designed a hypo-electronegativity atom mediated Pt-based high-entropy alloy regulation strategy. This approach exploits the electronegativity difference between Zn and Pt to induce the enrichment of Bader charges on the Pt atom surface, thereby enhancing the adsorption properties of Pt atoms and lowering the reaction energy barriers during the AOR process. Consequently, the appropriately Zn-mediated Pt-based high-entropy alloy achieves a peak current density of 351.5 A gPt–1 at ambient temperature (25 °C), which is 2.5 times higher than that of commercial Pt/C under comparable conditions. Notably, a peak power density of 4.67 mW cm–2 can be achieved at 25 °C for a low-temperature DAFC using the Pt-6HEAs-Zn18 as the anode catalyst. The Zn-mediated Pt-based high-entropy alloy strategy we designed provides valuable insights for the development of other efficient AOR catalysts that can achieve ampere-level current densities.
研究领域:
电化学
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催化
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材料科学
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能量转换
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表面科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED MATERIALS
·
2025
·Vol. 37
·期 41
·e08371
·
IF 26.8
Tong Wu,Xingyu Wang,Qin Yang,Bingqing Wang,Ruoou Yang,Shin-An Chen,Lo-Yueh Chang,Sibo Wang,Fuqiang Huang,Ziyun Wang,Yanwei Lum
Low-temperature direct ammonia fuel cells (DAFCs) can be used for the on-demand generation of clean electricity. However, such systems have low efficiency due to the kinetically sluggish ammonia oxidation reaction (AOR) and oxygen reduction reaction (ORR). Prior reports have largely focused on Pt-based electrocatalysts, however, their high cost motivates the need for simultaneously increasing activity whilst reducing the metal loading. Here, the design of a bifunctional Pt single-atom catalyst (SAC) is reported, with enhanced catalytic activities compared to commercial Pt/C for both reactions. Notably, by modulating the Pt SAC coordination, the optimal catalyst (Pt-DG-1) displayed a high AOR mass activity of 1.23 A mg Pt −1 and ORR mass activity of 7.98 A mg Pt −1 . This is then integrated into a DAFC as both the cathode and anode, achieving a peak power density of 21.8 mW cm −2 and low Pt mass loading of only 0.034 mg cm −2 . In situ shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) experiments on Pt-DG-1 indicate a lower * OH coverage under ORR conditions and suppressed formation of poisoning species * NO x under AOR conditions as additional reasons for its enhanced bifunctional catalytic activity. Importantly, the study demonstrates how SACs can be rationally designed for DAFC electrocatalysis.
研究领域:
电催化
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能源材料
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纳米催化
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燃料电池
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表面科学
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谱学分析
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Physical Chemistry Letters
·
2025
·
IF 4.6
Xiaohui Xu,Yu Cheng,Xinnan Xu,Weidong Tang,SiSi Liu,Chunlin Mu,Yinshi Huang,Baocong Guo,Chenglin Yan,Tao Qian
Ammonia is a hydrogen-dense, carbon-neutral energy carrier, but sluggish oxidation kinetics and catalyst toxicity limit its large-scale use in low-temperature alkaline direct ammonia fuel cells (DAFCs). Inspired by the “Grotthuss hopping” theory, we designed a hydroxyl group-modified membrane electrode catalyst system through the modification of interface key groups. This system can interact with adsorbed OH– (hereafter, OH–ad), thus being similar to a “relay” that allows OH–ad to jump from one active site to another and then react with ammonia intermediates, injecting more impetus into the kinetic process of the orderly release of OH–ad. The results of molecular dynamics (MD) simulations and operando Fourier transform infrared spectroscopy (operando-FTIR) further demonstrated and confirmed that this process follows the Gerischer–Mauerer (G–M) mechanism. Consequently, the mass activity of the best membrane electrode catalyst in this series, PtNiNC@OH0.05 (373 A g–1Pt), has been significantly enhanced in alkaline media, which is 3.2 times higher than that of the commercial 20% Pt/C (116 A g–1Pt) catalyst. Even more surprisingly, the DAFC of the membrane electrode catalyst as an anode achieves a peak power density of 17.4 mW cm–2 at 60 °C, which is 9.89-fold higher than that of 20% Pt/C (1.76 mW cm–2). The interface modification method based on the “relay” jumps proposed by us provides a way to fabricate DAFC membrane electrode catalysts.
研究领域:
能源材料
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电化学
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催化
·
燃料电池
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表面化学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Xu Lin,Xiaoran Zhang,Zhen Wang,Xinxin Zhu,Jinhui Zhu,Pinsong Chen,Taiyu Lyu,Changzheng Li,Zhi Qun Tian,Pei Kang Shen
Ammonia oxidation reaction (AOR) via electrocatalysis is one of the most efficient ways of utilizing ammonia (a zero-carbon fuel with high hydrogen content) for renewable energy systems. However, AOR seriously suffers from the slow kinetics, and low durability due to its multi-electron transfer process and the poison of the reaction intermediates (N ads and NO ads ) to precious metal catalysts. Herein, hyperbranched concave octahedral nanodendrites of PtIrCu (HCOND) with high-index facets of {5 5 3}, {3 3 1} and {2 2 1} were developed for the first time using a solvothermal method . The HCOND possesses PtIr-rich edges and exhibit highly efficient AOR activity and stability in alkaline media, wherein their onset potential is 0.35 V vs. RHE, which is 60 mV and 160 mV lower than that of the PtIrCu nanoparticles (NPs) (0.41 V) and commercial Pt/C (0.51 V), respectively, and its high mass activity of 40.6 A g PtIr -1 at the 0.5 V vs. RHE is 10.3 times, 2.34 times higher than that of commercial Pt/C (3.9 A g Pt -1 ) and PtIrCu NPs (17.3 A g PtIr –1 ), respectively. In addition, its peak current density (122.9 A g PtIr -1 ) is only reduced by 17.7% after 2000-cycles accelerated durability test. Meanwhile, the performance of PtIrCu HCOND is also better than that of other previously reported morphologies of Pt based catalysts (eg. nanoparticles, nanocubes, nanofilm , nanoflowers). The improvement is critically ascribed to unique advantages of the specific HCOND structure including PtIr rich surface, high-index faceted nanodendrites, strong lattice strain and electronic effects. These characteristics endow the HCOND with great promise to reduce Pt and Ir loading dramatically in the practical application of direct ammonia fuel cells.
研究领域:
电化学
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材料科学
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催化
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能源材料
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纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）