FUEL
·
2024
·
IF 6.7
Jia Shen,Chen Chen,Lichuan Song,Liding Zhong,Kai Shan,Yanglong Guo,Wangcheng Zhan,Yun Guo,Haifeng Wang,Li Wang
The anchoring effect between surface hydroxyls (–OH) and metal species has been extensively utilized to enhance catalyst stability. Nevertheless, few studies have investigated the impact of alloying process involving different types of –OH species. In this research, we discovered that the formation of the alloy particles Pt 3 Co was significantly influenced by the presence of distinct –OH species on Al 2 O 3 . Intriguingly, those Pt 3 Co alloy particles exclusively formed on α-Al 2 O 3 owing to the weak interaction between both Pt and Co species and the triply bridging hydroxyls (µ 3 -OH). In contrast, Pt and Co species were found to be separately dispersed on γ-Al 2 O 3 because of the strong anchoring effect of terminal hydroxyls (µ 1 -OH), especially for Co atoms. Density functional theory (DFT) calculations highlighted the difference in adsorption energies of the two metals on different hydroxyl groups, providing a theoretical rationale for the influence of hydroxyl groups on alloy formation. The presence of Pt 3 Co alloy resulted in a fourfold increase in the specific catalytic rate of Pt 3 Co/α-Al 2 O 3 in CO-PROX compared to Pt 3 Co/γ-Al 2 O 3 . Arguably for the first time, this study demonstrates the association between alloy formation and –OH groups, providing a unique perspective on the design of alloy catalysts.
研究领域:
催化化学
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材料科学
·
理论计算化学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2021
·
IF 4.539
Liting Xu,Yuhong Lv,Xingwei Li
The commercial development of direct methanol fuel cells (DMFCs) has been hampered by Pt anode catalysts with a high cost, and its long-term stability is also unsatisfactory, especially in acidic media. Therefore, the development of catalysts with high efficiency and low cost is an urgent problem. To reduce costs, a simple solution is to use non-precious transition metals to partially replace precious metal Pt. Moreover, the catalyst supports are also crucial in term of stabilizing and dispersing Pt-based catalysts. Herein, N-doped carbon-stabilized Pt 3 Co catalyst (Pt 3 Co/NC) is successfully prepared via the pyrolysis of Pt-encapsulated Co/Zn-based zeolitic imidazolate frameworks (Pt@ZIF-8/67). And catalytic performance of Pt 3 Co/NC catalyst is studied in 0.5 M H 2 SO 4 solution containing 0.5 M CH 3 OH. The area specific activity of Pt 3 Co/NC catalyst is 1.15 mA cm −2 Pt, which is about 4 times as great as that of commercial Pt/C. Furthermore, the as-prepared catalyst also shows better stability compared to Pt/C.
研究领域:
能源材料
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
NANOTECHNOLOGY
·
2020
·Vol. 31
·期 45
·455605
·
IF 3.551
Qingyu Luo,Sihao Wang,Yingfang Zhu,Shaolong Tang,Youwei Du
Structurally ordered Pt3Co/C nanoparticles (NPs) were obtained via a spray paint drying method with an annealing treatment. The addition of a suitable dose of polyvinylpyrrolidone resulted in a narrow size distribution of the Pt3Co/C-600-1 NPs, an average particle size of ca. 4.6 nm, which may be due to the enhanced dispersion in aqueous solution resulting from the carbon support. The sample denoted as Pt3Co/C-600-1 NPs performs high activity for oxygen reduction reaction with the mass activity (MA) ca. 3 times higher than that of a commercial Pt/C catalyst at 0.9 V. Accelerated durability tests (ADTs) showed that Pt3Co/C-600-1 NPs exhibit superior stability with a minimal loss of 17.5% in MA at 0.9 V after 5000 cycles, while Pt/C catalysts show loss of 44.4%. This simple two-step strategy provides an effective way to prepare Pt-based catalysts for industrial application.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Xiao-Feng Han,Nadia Batool,Wen-Tao Wang,Hao-Tian Teng,Li Zhang,Ruizhi Yang,Jing-Hua Tian
Simple and reliable mass production of platinum-based alloy catalysts with excellent activity and stability is an enormous challenge for the wide commercialization of proton-exchange membrane fuel cells (PEMFC), especially those with ultralow loading of Pt. Herein, an economical, highly durable, and efficient catalyst consisting of structurally ordered intermetallic Pt3Co alloy nanoparticles with ultralow Pt loading (1.4 wt %) supported on hierarchically porous carbon structure (three-dimensional, 3D Pt3Co/C) were synthesized with large-scale production by the NaCl-template-assisted approach. The obtained best sample, 3D Pt3Co/C#1, exhibited mass activities of 11.56 and 0.70 A mgPt–1 for oxygen reduction reactions (ORRs) in alkaline and acidic electrolytes, which are 60.8 and 6.4 times those of commercial Pt/C, respectively. Furthermore, the 3D Pt3Co/C#1 exhibited excellent stability both in acidic and alkaline electrolytes, with almost no decay of the half-wave potential after 5000 potential cycles. This work proposes a new high-yielding, simple, and environmentally friendly method to fabricate excellent Pt-based alloy electrocatalysts with ultralow loading of Pt, which opens up new hopes for the development of PEMFC.
研究领域:
材料科学
·
电化学
·
燃料电池
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2020
·
IF 7.632
Yanyan Gao,Ming Hou,Liang He,Manman Qi,Haiping Chen,Wenzhe luo,Zhigang Shao
To enhance the performance and durability of proton-exchange membrane fuel cells (PEMFCs), we looked beyond the polymer-skeleton electrospinning electrode and developed a novel carbon-skeleton nanofiber electrode (the C-spun electrode) by a facile heat-treatment process. After thermal annealing at 600 °C, part of the disordered Pt3Co nanoparticles converted into an ordered intermetallic phase, with an apparently improved oxygen reduction reaction (ORR) activity (E1/2 increased by 50 mV). Meanwhile, the polymers in the polymer-skeleton nanofibers were carbonized and transformed into carbon skeletons, which exhibited excellent corrosion resistance during extensive carbon corrosion testings (1.0–1.5 V, 0.5 V s–1, 1600 rpm, 30 000 cycles). In unit-cell tests, the C-spun electrode achieved an excellent performance of 8.207 W mgPt–1 (H2/air, 80 °C, 1 bar, 100% RH), which is higher than that of the previously reported electrodes with commercial Pt3Co/C. After 50 000 potential scanning cycles, a negligible performance loss was observed. The C-spun electrode provides a new direction for the next-generation electrodes of PEMFCs.
研究领域:
材料科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2024
·
IF 20.2
Weiping Xiao,Daqiang Yan,Qin Zhao,Danil Bukhvalov,Xiaofei Yang
Developing the Pt-based intermetallic nanoparticles could accelerate the sluggish kinetic of oxygen reduction reaction, while it remains a great challenge to explore efficient synthesis strategies enhancing thermal stabilities and electrocatalytic properties. This work employed the metal-support coupling strategy to construct the Pt 3 Co/CoNC hierarchical nanostructure , where the well-dispersed atomically ordered Pt 3 Co nanoparticles were anchored on the Co-NC sites. Physical structure analysis combined with density functional theory calculations demonstrated the strong coupling effect between Pt and surrounding Co-NC sites, which could weaken the activation energy to break O-O bonds and enhance the intrinsic activity and stability of Pt. Hence, the Pt 3 Co/CoNC exhibited the optimized ORR activities with the half-wave potentials of 0.97 V in KOH solution and displayed the peak power density of 187 mW cm −2 as the cathode of Zn-air battery. This metal-support coupling strategy can be further generalized and improved to synthesize other Pt-based catalysts with efficient electrocatalytic properties.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2024
·
IF 5.4
Mingjie Xu,Ye Xiao,Tianli Liu,Hailong Wang,Bingbing Fan,Yanhao Dong,Chang-An Wang
Proton exchange membrane fuel cells (PEMFCs) have received extensive attention in electric vehicles and drones because of their high energy and power density. However, the performance of the PEMFCs is limited by the slow kinetic process of cathodic oxygen reduction. It is necessary to develop efficient catalysts with a low cost, high activity, and good electrochemical stability. Pt–M (M = Fe, Co, Ni, Cu, etc.) alloy catalysts are among the top candidates. The lattice of Pt shrinks when charge transfer from M to Pt occurs, which lowers the energy of the d-band of Pt. It not only balances the adsorption and desorption energies of oxygen-containing intermediates but also improves the stability of catalytic sites. In this study, we report a Pt3Co alloy catalyst supported on a N-doped carbon supports. The catalyst exhibits excellent ORR activity and outstanding durability performance as compared with the commercial JM Pt/C catalyst. The half-wave potential before and after accelerated durability testing is more positive, and the mass activity and the specific activity are much higher than the commercial Pt/C in both 0.1 M KOH and 0.1 M HClO4. Besides, the hydrogen evolution reaction performance has also been significantly improved compared to the Pt/C catalyst. This method is simple and feasible, which offers a strategy for the synthesis of high-performance electrocatalysts for PEMFCs.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
IONICS
·
2021
·Vol. 27
·期 6
·2553-2560
·
IF 2.817
Cheng Zhenzhi,Liao Sen,Zhou Weiping,Luo Guangsheng,Huang Haifu
We developed a solid phase method to fabricate structurally ordered Pt 3 Co/C nanoparticles (NPs) with controllable component proportion as a high efficiency catalyst toward oxygen-reduction reaction. As a result, Pt 3 Co/C NPs exhibit high crystallinity with small average size and narrow size distribution. Moreover, the ordered Pt 3 Co/C NPs own enhanced ORR catalytic performance in acid. During the preparation process, the NaCl-matrix acts synergistically with carbon black as nanoreactors for Pt alloying with Co, avoiding serious sintering resulted by annealing at high temperature. Furthermore, other Pt-based NPs supported on carbon can also be prepared by this methodology.
研究领域:
材料科学
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电化学
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
IONICS
·
2023
·Vol. 29
·期 5
·1991-2003
·
IF 2.8
Yuhui Cui,Jinghao Lu,Lijuan Yang,Zheng Hao,Runjin Wu,Qian Li,Shijia Xu,Libin Yang
In proton exchange membrane fuel cells (PEMFCs), the most advanced catalysts are mainly carbon loaded with platinum (Pt), but the cathodic catalytic active center is too low to match the oxidation activity and rate at the anode. Co atoms doped into the lattice of Pt alloy change the electronic structure of platinum and reduce the binding energy of oxygen atoms. Au or Rh atoms embedded into the lattice of Pt 3 Co alloy compensate the defect and enhance the activity and rate of the oxygen reduction. Through base on density functional theory (DFT), the adsorption energy for oxygen on Pt 3 Co, Au-Pt 3 Co, and Rh-Pt 3 Co and the segregation energy of Co atoms were calculated. The results show that Au or Rh doped weakens the binding energy of Pt for oxygen on the Pt 3 Co alloy and improves the activity and stability of oxygen reduction. Compared with Rh, the introduction of Au element shows better effects in the electrocatalytic reaction process. Graphical Abstract
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
SmartMat
·
2021
·Vol. 2
·期 2
·234-245
·
IF 0
Niuwa Yang,Dong Chen,Penglei Cui,Tingyu Lu,Hui Liu,Chaoquan Hu,Lin Xu,Jun Yang
Heterogeneous nanocomposites comprising chemically distinct constituents are particularly promising in electrocatalysis. We herein report a synthetic strategy that combines the reduction of Pt and Co ionic precursors at an appropriate ratio with the subsequent phosphating at an elevated temperature for forming heterogeneous nanocomposites consisting of quasi-spherical Pt 3 Co alloy domains and rod-like CoP 2 domains for high-efficiency methanol electro-oxidation. The strong electronic coupling between Pt 3 Co and CoP 2 domains in the nanocomposites render the electron density around Pt atoms to decrease, which is favorable for reducing the adsorption of poisoning CO-like intermediates on the catalyst surfaces. Accordingly, the as-prepared heterogeneous Pt 3 Co–CoP 2 nanocomposites show good performance for methanol electro-oxidation both in acidic and alkaline media. In specific, at a Pt loading of only 6.4% on a common carbon substrate, the mass-based activity of Pt 3 Co–CoP 2 nanocomposites in an acidic medium is about 2 and 1.5 times as high as that of commercial Pt/C catalyst (20% mass loading) and home-made Pt 3 Co alloy nanoparticles (8.0% mass loading), while in the alkaline medium, these values are 3 and 2, respectively.
研究领域:
材料科学
·
电化学
·
催化作用
✓ 已验证
产品关联
DOI
ACS Applied Energy Materials
·
2022
·
IF 6.959
Jie-wen Liu,Jian Zhang,Ming-jie Xu,Chuan-jin Tian,Xiao-jun Zeng,Chang-an Wang
Developing highly active and reliable Pt-based catalysts is a major challenge for the widespread commercialization of proton-exchange membrane fuel cells. Herein, we have designed Pt3Co@C hollow sphere catalysts by the template method, in which PtCo alloy nanoparticles of approximately 3 nm diameter are anchored in a porous shell of nitrogen-doped carbon hollow spheres. Due to the confinement effect of the porous carbon shell, PtCo alloy nanoparticles possess excellent resistance to sintering, maintaining 2–3 nm size after calcination at 800 °C. Also, Pt3Co@C hollow sphere catalysts exhibit superior catalytic activity and stability in the oxygen reduction reaction, achieving 3.6 times the mass activity of the corresponding commercial Pt/C catalyst. Such catalysts with a mass activity retention rate of 87% after accelerated durability testing and no significant decay in activity after 10,000 potential cycles. Meanwhile, Pt3Co@C catalysts exhibit extremely high catalytic activity and surprising durability for the hydrogen evolution reaction process over the entire pH range. We believe that this methodology provides an insight into the preparation of high-performance electrocatalysts.
研究领域:
材料科学
·
电化学
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2023
·Vol. 11
·期 8
·4078-4087
·
IF 11.9
Weicheng Xu,Zhipeng Zhu,Yucheng Wang,Peixin Cui,Lei Tong,Kuangmin Zhao,Jiayin Yuan,Zhi-You Zhou,Hai-Wei Liang,Na Tian,Shi-Gang Sun
Ordered intermetallic Pt–M alloys are foreseen to be promising as next-generation low-Pt catalysts for the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs) due to their high catalytic activity and stability. Nevertheless, the disorder-to-order intermetallic phase transition often needs to proceed at elevated annealing temperature for a long time, which leads to severe particle agglomeration. Herein, an efficient nitrogen (N)-doping strategy is developed to speed up such phase transition in an intermetallic Pt3Co alloy catalyst, which shortens the annealing duration by 3–5 fold at a temperature of 600–800 °C. Such a strategy can not only minimize the particle agglomeration but also effectively optimize the electronic structure of surface Pt atoms with the incorporated N. The prepared N-doped ordered intermetallic Pt3Co catalyst exhibits high ORR activity among the best of the state-of-the-art, with mass activities of 1.21 and 1.20 A mgPt−1 at 0.90 V in rotating disk electrode (RDE) and proton exchange membrane fuel cell (PEMFC) tests, respectively. Moreover, with the total Pt loading of 0.15 mgPt cm−2, the H2–air PEMFC delivers a power density of 1.27 W cm−2 at 150 kPaabs and 0.6 V, corresponding to a high Pt utilization of 0.118 gPt kW−1 that has surpassed the DOE 2025 target (0.125 gPt kW−1). This study paves a new way to develop high-performance low-Pt ORR catalysts for PEMFCs.
研究领域:
材料科学
·
能源科学
✓ 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）