Nature Communications
·
2025
·Vol. 16
·期 1
·1-11
·
IF 15.7
Wang Dawei,Lin Fangxu,Luo Heng,Zhou Jinhui,Zhang Wenshu,Li Lu,Wei Yi,Zhang Qinghua,Gu Lin,Wang Yanfei,Luo Mingchuan,Lv Fan,Guo Shaojun
Using metal oxides to disperse iridium (Ir) in the anode layer proves effective for lowering Ir loading in proton exchange membrane water electrolyzers (PEMWE). However, the reported low-Ir-based catalysts still suffer from unsatisfying electrolytic efficiency and durability under practical industrial working conditions, mainly due to insufficient catalytic activity and mass transport in the catalyst layer. Herein we report a class of porous heterogeneous nanosheet catalyst with abundant Ir-O-Mn bonds, achieving a notable mass activity of 4 A mg Ir −1 for oxygen evolution reaction at an overpotential of 300 mV, which is 150.6 times higher than that of commercial IrO 2 . Ir-O-Mn bonds are unraveled to serve as efficient charge-transfer channels between in-situ electrochemically-formed IrO x clusters and MnO x matrix, fostering the generation and stabilization of highly active Ir 3+ species. Notably, Ir/MnO x -based PEMWE demonstrates comparable performance under 10-fold lower Ir loading (0.2 mg Ir cm −2 ), taking a low cell voltage of 1.63 V to deliver 1 A cm −2 for over 300 h, which positions it among the elite of low Ir-based PEMWEs.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Energies
·
2022
·Vol. 15
·期 8
·2732
·
IF 3.252
Xia Sheng,Chunyu Ru,Honghui Zhao,Shouyi Jin,Bowen Wang,Yupeng Wang,Linghai Han,Kui Jiao
Hydrogen starvation leads to the extreme deterioration of fuel cell performance due to the induced voltage reversal and carbon corrosion in the anode catalyst layer (ACL) and gas diffusion layer. In this paper, reversal-tolerant anodes (RTAs) with different ACL configurations are proposed, where IrOx/C is used as a water electrolysis catalyst. Experimental results show that the separate IrOx/C catalyst layer of MEA samples, layered reversal-tolerant catalyst-coated membrane (layered-RTA), and reversal-tolerant gas diffusion electrode (GDE-RTA) significantly enhance the reversal tolerance and cell performance compared to conventional anode and common RTA consisting of a homogeneous catalyst layer mixed with IrOx/C and Pt/C (hybrid-RTA). Of these, GDE-RTA possessed a reversal tolerance time of 86 min, a power density of 1.42 W cm−2, and a minimum degradation rate of 2.4 mV min−1, suggesting it to be the best RTA structure. Cyclic voltammetry and electrochemical impedance spectrum were used to detect the properties of each sample. Additionally, the degradation mechanisms of the three RTAs are thoroughly investigated and discussed by means of microstructural characterization through scanning electron microscopy and transmission electron microscopy. This work provides novel ideas for the fabrication of a robust RTA by tuning the ACL configuration, which is practical for the commercialization of fuel cells.Keywords:fuel cell;hydrogen starvation;reversal tolerance;catalyst layer configuration;degradation mechanism
研究领域:
能源科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2023
·
IF 6.4
Siqi Fang,Guoliang Liu,Minghai Li,Haining Zhang,Jun Yu,Fangfang Zhang,Mu Pan,Haolin Tang
Reducing the local oxygen transport resistance in the cathode catalyst layer of the proton exchange membrane fuel cell (PEMFC) is crucial for the improvement of cell performance, particularly for low platinum loading. In this work, we report that the performance of PEMFC can be significantly improved by replacing Nafion with a highly oxygen-permeable perfluoronated ionomer containing dioxole segments on the backbone as both proton conductor and catalyst binder in the cathode catalyst layer, as evidenced by the increased peak power density of 100 mW cm–2. Molecular dynamics simulation results reveal that the synthesized ionomer has higher diffusion coefficient and higher oxygen solubility compared with Nafion. Benefiting from the high oxygen permeability, both the specific activity and mass specific activity of a Pt/C catalyst using the designed ionomer as catalyst binder for the oxygen reduction reaction are three times higher than those of a catalyst using Nafion as catalyst binder. The results demonstrate that the rational design of highly oxygen-permeable ionomers applied in the catalyst layer could be an effective strategy for a high-performance PEMFC with low platinum loading.
研究领域:
能源科学
·
材料化学
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2018
·
IF 3.024
Yong Jiao,Liyang Wang,Liqin Zhang,Wenting An,Wei Wang,Wei Zhou,Moses O. Tadé,Zongping Shao,Jianping Bai,Si-Dian Li
This paper studies the electrochemical feasibility of the direct conversion of low-concentration, oxygen-bearing coal-bed methane (CBM, 30 vol % CH4) to electricity via solid oxide fuel cells (SOFCs). A fuel cell with the LiLaNi–Al2O3/Cu catalyst layer was developed, and a maximum power output of ∼1068 mW cm–2 was achieved at 850 °C using 30 vol % CBM fuel, which is only modestly lower than that from a cell based on hydrogen fuel. The stability test showed that the cell operation was quite stable during the 120-h test period, which is ∼40-fold longer than that of the cell without catalyst layer. The partial oxidation of methane (POM) occurring in the anode may play an important role when using 30 vol % CBM fuel, which not only supplies highly active gaseous fuels (H2 and CO) but also suppresses the carbon deposition on the anode. By modifying the anode with a LiLaNi–Al2O3/Cu catalyst layer, the POM of 30 vol % CBM was further promoted and the carbon deposition over the anode was mitigated more efficiently. Therefore, the strategy of direct conversion of low-concentration, oxygen-bearing CBM via the SOFCs with an anode catalyst layer may pave an alternative way to utilize this abundant resource efficiently and cleanly.
研究领域:
能源科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Nano
·
2024
·
IF 15.8
Lei Wan,Dongcheng Lin,Jing Liu,Ziang Xu,Qin Xu,Yihan Zhen,Maobin Pang,Baoguo Wang
Developing a high-efficiency and stable anode catalyst layer (CL) is crucial for promoting the practical applications of anion exchange membrane (AEM) water electrolyzers. Herein, a hierarchical nanosheet array composed of oxygen vacancy-enriched CoCrOx nanosheets and dispersed FeNi layered double hydroxide (LDH) is proposed to regulate the electronic structure and increase the electrical conductivity for improving the intrinsic activity of the oxygen evolution reaction (OER). The CoCrOx/NiFe LDH electrodes require an overpotential of 205 mV to achieve a current density of 100 mA cm–2, and they exhibit long-term stability at 1000 mA cm–2 over 7000 h. Notably, a breakthrough strategy is introduced in membrane electrode assembly (MEA) fabrication by transferring CoCrOx/NiFe LDH to the surface of an AEM, forming a 3D-interlocked anode CL, significantly reducing the overall cell resistance and enhancing the liquid/gas mass transfer. In AEM water electrolysis, it exhibits an ultralow cell voltage of 1.55 Vcell to achieve a current density of 1.0 A cm–2 in 1 M KOH, outperforming the state-of-the-art Pt/C//IrO2. This work provides a valuable approach to designing high-efficiency electrocatalysts at the single-cell level for advanced alkaline water electrolysis technologies.
研究领域:
材料科学
·
电化学
·
可再生能源
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2020
·
IF 4.939
Aidi Han,Cehuang Fu,Xiaohui Yan,Junren Chen,Xiaojing Cheng,Changchun Ke,Junbo Hou,Shuiyun Shen,Junliang Zhang
With the wide use of platinum alloy electrocatalysts proton exchange membrane fuel cells, the dissolution of transition metal in the acid environment of catalyst layer becomes a major concern due to the decreased catalytic activity during long-term operation. Although great efforts have been done, few attention is paid to the effect of transition metal ion contamination of Nafion ionomer that wrapped around catalyst particles within catalyst layer which might greatly influence the proton conduction. To elucidate such effect, ultrathin Nafion film on SiO 2 model substrate is prepared via self-assembly method to represent the ionomer in fuel-cell catalyst layers, and the ultrathin film with specific thickness is further equilibrated in Co(NO 3 ) 2 /HNO 3 solutions with different Co 2+ concentration to achieve different doping level. Conductivity measurements demonstrate that the non-precious metal contamination severely worsens proton conduction of Nafion ionomer, but it is always ignored before. In addition, when the occupation of H + in Nafion ionomer is less than 50%, the activation energy shows a sharp increase, indicating a possible change in proton conduction mechanism.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Li Guan,Weibin Yu,Muhammad Rehman Asghar,Weiqi Zhang,Huaneng Su,Chunsheng Li,Lei Xing,Qian Xu
Efficient methanol oxidation reaction is the first requirement of the electrocatalyst of a Direct methanol fuel cell (DMFC), which is determined by its catalyst material and preparation method. In this work, a novel electrocatalyst used in anode is prepared by using graphene aerogel (GA) as a supporting material with platinum and Nafion binder by spray coating. The physical and chemical properties of the electrocatalyst are examined with scanning electron microscope (SEM), Electrochemical impedance spectroscopy (EIS), and polarization curves. The SEM results show that graphene aerogel based electrocatalysts possess a three-dimensional structure with uniform dispersion of nanostructure, which enlarges the activation area of the electrocatalyst and produces more protons and electrons. Moreover, the well-developed porous structure provides a less resistance and smooth pathway for protons to reach the cathode. The results show that with 10 % GA and 50 % Nafion as binder, the current density reaches at the value of 42.62 mW·cm −2 respectively, which is 13.5 % higher than the maximum power density of 37.56 mW·cm −2 of traditional carbon-catalyst layer (C-CL) electrode. Moreover, when temperature increases from 50 to 70 ℃, the novel catalytic layer electrode (GA-CL) doped with GA as an additive delivers 95.8 % increment in power density.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
ChemElectroChem
·
2020
·Vol. 7
·期 7
·1775-1780
·
IF 4.154
Xinyue Zhang,Qingtao Liu,Jianglan Shui
Graphical Balancing act : Polytetrafluoroethylene (PTFE) is added to different positions of the Fe−N−C catalyst layer by using three methods to adjust its hydrophobicity. An appropriate amount of PTFE in the Fe−N−C catalyst layer is beneficial to the power density of the PEM fuel cell. However, the hydrophobicity of the Fe−N−C catalyst layer does not affect the long-term durability of the fuel cells, although high hydrophobicity will improve the fuel cell initial durability. The hydrophobicity of the cathode catalyst layer (CCL) affects the performance of the proton exchange membrane fuel cell (PEMFC) by adjusting the water management of the catalyst layer, which has been extensively studied in Pt-based catalysts. Here, the effect of the hydrophobicity of Fe−N−C CCL on the performance of the PEMFC is investigated. The hydrophobicity of the Fe−N−C CCL is tuned by polytetrafluoroethylene (PTFE) by using three addition methods: 1) coat PTFE on Fe−N−C powder and heat-treat; 2) mix PTFE emulsion with Fe−N−C ink and then brush the electrode; and 3) transfer a ground PTFE/Fe−N−C composite film onto the gas diffusion layer by the decal method. For each PTFE addition method, the optimized PTFE amount can increase the power density of Fe−C−N PEMFC by 15.1 %, 26.6 %, and 87.2 %, respectively. At the same time, it is found that enhanced hydrophobicity reduces the initial current decay rate of the Fe−N−C CCLs, but their residual current densities are close after a 50 h durability test at 0.5 V in a H 2 -O 2 PEMFC. It can be concluded that the hydrophobicity of the Fe−N−C CLL has a great influence on the power density of the fuel cell, but the influence on the long-term durability of the fuel cell is negligible.
研究领域:
能源科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2022
·
IF 9.794
Wenbo Sui,Wangzu Li,Zhongshuo Zhang,Weixing Wu,Zhanyou Xu,Ying Wang
Electrochemical synthesis of hydrogen peroxide (H 2 O 2 ) through 2-electron oxygen reduction reaction (ORR) is a sustainable alternative to the industrialized anthraquinone oxidation process . Gas-diffusion electrode (GDE) is employed to overcome the mass transport limitation of O 2 to deliver high current density . However, long-term stability in practical electrolyzer with GDE is still challenging due to electrode flooding. Here, we propose a double catalyst layer (CL) strategy with gradient Nafion distribution to balance the mass transport of O 2 and H + and improve the flood-proof ability. Our design achieved H 2 O 2 production rate up to 2.16 mmol h −1 cm −2 with a selectivity of about 90% and enabled 48 h stable electrolysis at 100 mA cm −2 . Compared to the state-of-the-art H 2 O 2 electrosynthesis system in acidic media, the full-cell voltage improved significantly to 2.3 V at 100 mA cm −2 , indicating its potential for practical production and utilization.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
ChemElectroChem
·
2025
·
IF 3.5
Ziang Wang,Zhaoping Shi,Yuqing Cheng,Ming Yang,Jinsheng Li,Zhao Jin,Meiling Xiao,Changpeng Liu,Wei Xing
Graphical This work develops an in situ pore-forming strategy to construct cross-linked porous catalyst layers (PCL) for proton exchange membrane water electrolysis. The PCL exhibits 2.1times the electrochemical active area of conventional catalyst layers, achieving 3.8 A cm −2 @1.9 V (exceeding U.S. Department of Energy 2025 targets) and 1600-hour stability at 2 A cm −2 . Engineering catalyst layer structure is of significant importance to improve the performance and durability of proton exchange membrane water electrolysis (PEMWE), yet rare efficient design strategies has been reported. This work develops an in situ pore-making approach to construct cross-linked porous catalyst layer, which significantly improves catalyst active site utilization compared to conventional catalyst layer (CCL). The electrochemical activity area of the porous catalyst layer membrane electrode assemblies (MEA) (52.22 cm 2 mg Ir −1 ) is 2.10 times higher than that of the CCL-MEA (24.90 cm 2 mg Ir −1 ), which indicates that more active sites are exposed during pore-making process, leading to the higher utilization efficiency of the electrocatalyst. As a result, the porous catalyst layer exhibits a high current density of 3.8 A cm −2 at 1.9 V, which is exceeding the U.S. Department of Energy 2025 target (3 A cm −2 @1.9 V), and shows superior durability with no significant degradation after 1600 h of operation at a constant load of 2 A cm −2 . Scanning electron microscope analysis confirms the structural integrity of the porous catalyst layer, while cracks formed in the CCL during testing. These results highlight the benefits of the porous structure in improving mass transport, stability, and overall performance in PEMWE applications.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2021
·
IF 19.503
Weikang Zhu,Yabiao Pei,John C. Douglin,Junfeng Zhang,Haoyang Zhao,Jiandang Xue,Qingfa Wang,Ran Li,Yanzhou Qin,Yan Yin,Dario R. Dekel,Michael D. Guiver
Recently, much work has been devoted to designing catalysts with high porosity and efficient active sites. Although very promising results are achieved using Co/Fe–N–C catalysts based on rotating disk electrode (RDE) tests, actual fuel cell performance is below expectations, probably due to insufficient understanding of the catalyst layer (CL). Therefore, catalyst design should be considered holistically by taking into account CL performance, not only intrinsic activity. Here, Co/Fe–N–C with highly dispersed CoFe nanoalloy in the carbon network is obtained by careful design of Co/Fe-ZIF precursor, resulting in a high oxygen reduction reaction (ORR) site density with good stability. Concerning RDE test in the kinetic region and single cell test (SCT) with complex influence factors, the half-cell test (HCT) is introduced to more accurately evaluate the quality of the Co/Fe–CL. Multi-scale measurements (RDE, HCT and SCT) in different current density ranges allows targeting the key CL influence factors for fuel cell performance.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2020
·
IF 8.247
Xun Zhu,Yuan Zhou,Ding-Ding Ye,Rong Chen,Tong Zhang,Qiang Liao
Microfluidic fuel cells is one of the most promising micro power sources for the portable micro-electronic devices. Facing the requirement of high performance, in this work, a novel air-breathing microfluidic fuel cell (AMFC) with discrete-holes film fueling anode is developed by inputting the idea of gas film cooling, where fuel is fed into the capillary tube and then outflows through the discrete holes to fuel the catalyst layer by annular film flow, enabling fuel transfer enhancement. Idea of the new AMFC architecture is realized, and the annular film flow based on film fueling is visualized and proved by fluorescence microscopy at various flow conditions. In addition, the cell performances under various annular film flow patterns are compared at equal total fuel supply. The effects of fuel concentration and fuel flow rate on fuel transport and cell performance are investigated and discussed in detail. And the maximum power density of 361.9 mW cm −3 is obtained. These results are in favor of promoting the practical application of microfluidic fuel cells.
研究领域:
能源科学
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）