Journal of Materials Chemistry A
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2015
·Vol. 3
·期 13
·7093-7099
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IF 7.443
Jiaoxing Xu,Qiangmin Yu,Lunhui Guan
Hierarchically nanoporous N-doped carbon nanowires (N-CWs) were prepared by a novel space-confinement-induced assembly strategy, for which nitrogen-enriched pyrimidine and anodic aluminium oxide (AAO) template bearing metal oxides are employed as precursor and nanoscale channels, respectively, and the Fe/Co metal oxide not only blocks the AAO surface from the original surface-templating carbonization, but also introduces nanoporosity with acid etching. Thus-obtained carbon nanowires composed of N-doped graphene-like carbon nanosheets not only contain a high N content (up to ∼12%), but also possess a hierarchically meso/microporous structure (∼1.3 cm3 g−1) with high specific surface area (∼455 m2 g−1). This protocol allows for the simultaneous optimization of graphitization, porous structure and surface functionalization. As a result, the prepared N-CWs demonstrate an attractive electrocatalytic capability towards oxygen reduction reaction (ORR). Specifically, in addition to the improved kinetic current density and overpotential, the N-CWs prepared at 700 °C show the optimized ORR performance with an electron-transfer number of ∼4.0, which very close to that of a commercial Pt/C catalyst.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
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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
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电化学
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燃料电池
✓ 已验证
DOI
高影响因子
ChemCatChem
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2024
·
IF 3.8
Ke Wan,Zhi Li,Yangfan Sun,Xin Zhang,Jiayi Fang,Qingshan Li,Yuanna Sun,He Miao
Graphical Oxygen vacancies were introduced into the perovskite LaMnO 3 using a carbon reduction process. LaMnO 3 was mixed with conductive carbon black in a 3:1 mass ratio, then heated at 500 °C for 2 h under an Ar atmosphere and allowed to cool naturally. The resulting novel composite material, LMOC-500, exhibited excellent catalytic activity and stability for the oxygen reduction reaction. Zinc-air batteries (ZABs) have garnered significant attention due to their high theoretical energy density, safety, and environmental sustainability. However, the slow oxygen reduction reaction (ORR) kinetics at the cathode remains a major challenge for improving ZAB performances. In this study, ABO 3 -type perovskite transition metal oxides, particularly LaMnO 3 , are explored as potential nonprecious metal catalysts to address these limitations. In this work, the LaMnO 3 catalyst was prepared using the sol-gel method, and oxygen vacancies were introduced through a novel carbon reduction approach using conductive carbon black as the reducing agent. The catalyst was reduced at different temperatures to optimize its ORR activity. The 500 °C-reduced sample (LMOC-500) shows the superior catalytic performances, achieving an onset potential of 0.937 V versus RHE and a half-wave potential of 0.824 V versus RHE. The optimized material also exhibited excellent stability in long-term discharge tests in ZAB applications, demonstrating its potential application as the ORR catalyst for ZABs.
研究领域:
材料科学
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电化学
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能源科学
✓ 已验证
DOI
高影响因子
ACS Nano
·
2025
·
IF 16
Yufei Yao,Hongyang Qu,Zehui Sun,Yequan Chen,Shenglong Yang,Wei Ma
Oxygen reduction reaction (ORR) plays a crucial role in both the chemical and energy industries. Despite substantial advancements in theoretical, computational, and experimental studies, identifying both the in situ activity and selectivity in ORR electrocatalysis remains a major challenge. Here, using a suite of correlative operando scanning electrochemical probe and electrochemiluminescence microscopy techniques, we establish a link between the morphological structure and the local ORR activity and selectivity of single Au and Au@Pt platelets at the subparticle level. It is clearly shown that the edge facets of Au and Au@Pt platelets exhibit higher activity for 4e– ORR compared to basal planes, whereas the basal planes of both Au and Au@Pt platelets demonstrate superior 2e– selectivity relative to the edge facets. These findings deepen our understanding of ORR activity and selectivity across different facets at the subparticle level, which offers valuable guidance for the rational design of highly efficient ORR electrocatalysts.
研究领域:
电化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Yajie Guo,Fuxian Zheng,Ting Wang,Xinyang Liu,Xiaotan Tian,Konggang Qu,Lei Wang,Rui Li,Wenjun Kang,Zongge Li,Haibo Li
Palladium (Pd)-transition metal alloys have the potential to regulate the intermediate surface adsorption strength in oxygen reduction reactions (ORR), making them a promising substitute for platinum-based catalysts. Nonetheless, prolonged electrochemical cycling can lead to the depletion of transition metals, resulting in structural degradation and poor durability. Herein, the synthesis of alloy catalysts (Pd25%Te75%) containing Pd and the metalloid tellurium (Te) through a one-step reduction method is reported. Characterizations of powder X-ray photoelectron spectroscopy, X-ray diffraction, and high-resolution transmission electron microscopy demonstrated both uniform dispersion and strong binding force of elements within the PdTe alloy, along with providing crystallographic details of associated compounds. Based on density functional theory calculations, PdTe had a more negative d-band center than that of pure Pd, which reduces the adsorption capacity between active sites and intermediates in the ORR, and therefore enhances reaction kinetics. The Pd25%Te75% exhibited excellent ORR activity, and its onset and half-wave potentials were ∼0.98 and ∼0.90 V, respectively, at 1600 rpm within the O2-saturated 1.0 M KOH. Significantly, accelerated durability tests achieved exceptional stability, and half-wave potential just decayed by 4 mV after 30000 consecutive cycles. Moreover, this study aims to promote the preparation of Pd and metalloid alloys for other energy conversion applications.
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
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2024
·
IF 5.8
Siyu Chu,Min Sun,Zijiong Li,Haiyan Wang,Feng Miao
The carbon-based catalysts exhibit excellent electrocatalytic and stable performance toward oxygen reduction reaction (ORR), which are expected to replace expensive and scarce Pt-based catalysts. However, how to regulate the interaction between silver and carrier carbon dots (CD) to improve electrocatalytic performance toward oxygen reduction reaction (ORR) and stability, has not been systematically studied. In this study, we in-situ synthesized fluorine and nitrogen co-doped CD anchoring Ag nanoparticles by UV irradiation reduction method. The peak potential, onset-potential and half-wave potential of F, [email protected] are 0.85 V, 1.056 V, and 0.9 V, respectively, indicating outstanding ORR performance. The current density of F, [email protected] remains 97.5 % after 50, 000 s, showing more excellent stability than Pt/C. The impressive ORR catalytic activity and stability of F, [email protected] could be attributed to the strong anchoring effect of nitrogen-doped CD on Ag. This effect leads to a significant interaction and charge transfer between Ag and CD, thereby enhancing the charge transfer process during the catalytic reaction. This project aims to design a carbon dot/silver composite catalyst with high ORR catalytic performance and favorable stability. The implementation of this project provides good theoretical guidance for the design of carbon nanomaterial-based catalytic systems.
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 Nano Materials
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2024
·
IF 5.3
Congyue Sun,Zhongcheng Zhao,Dongyan Xu,Xiaojin Li,Ke Ye
The rapid development of proton-exchange membrane fuel cells needs to develop Pt-based oxygen reduction reaction (ORR) catalysts with activity and stability. In this study, PtCu alloy nanoparticles were in situ anchored on an N-doped porous carbon (NC) derived from ZIF-8 with a chemical reduction method to produce a PtCu/NC catalyst with a Pt loading of 7.96 wt %. The PtCu alloy nanoparticles are uniformly immobilized on the NC with a high surface area via a metal–support interaction. The electrochemical test results demonstrated that the PtCu/NC catalyst displays remarkable activity with an E1/2 value of 0.913 V vs RHE, higher than 0.878 V vs RHE for the commercial Pt/C. The ORR mass activity of the PtCu/NC catalyst is 1.49 and 6.54 times that of PtCu/XC-72 and commercial Pt/C, respectively. The eminent ORR performance of PtCu/NC is attributed to the high specific area of NC and electron-rich Pt sites enhanced by electron transfer from the N and Cu atoms. Moreover, PtCu/NC exhibited better catalytic stability than PtCu/XC-72 and Pt/C after 3000 potential cycles, attributed to the interaction between the N atom and PtCu alloy.
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 Materials & Interfaces
·
2024
·
IF 8.3
Liming Guo,Xin Wan,Jieyuan Liu,Xu Guo,Xiaofang Liu,Jiaxiang Shang,Ronghai Yu,Jianglan Shui
Synergistic effects have been applied to a variety of hybrid electrocatalysts to improve their activity and selectivity. Understanding the synergistic mechanism is crucial for the rational design of these types of catalysts. Here, we synthesize a MnCo2O4/Co–N–C hybrid electrocatalyst for the oxygen reduction reaction (ORR) and systematically investigate the synergy between MnCo2O4 nanoparticles and Co–N–C support. Theoretical simulations reveal that the synergy is closely related to the distance between active sites. For a pair of remote active sites, the ORR proceeds through the known 2e- + 2e- relay catalysis while the direct 4e– ORR occurs on a pair of adjacent active sites. Therefore, the formation of the undesired byproduct (H2O2) is inhibited at the interface region between MnCo2O4 and Co–N–C. This synergistic effect is further verified on an anion-exchange membrane fuel cell. The findings deepen the understanding of synergistic catalysis and will provide guidance for the rational design of hybrid electrocatalysts.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2024
·
IF 3.9
Ziyu Liu,Xinyu Wang,Pengye Zhang,Haonan Zhang,Shuai Wang,Gaiyan Jiao,Wenting Wu,Mingbo Wu
The photosynthesis of hydrogen peroxide (H2O2) from oxygen (O2) represents a promising catalytic pathway, the limited efficiency of the oxygen reduction constitutes a primary barrier to enhancing production. In this content, alkali metal potassium (K+) and Br-doped g-C3N4 photocatalysts (K-CN) were successfully constructed by one-pot method. The introduction of K+ is not only beneficial to the transmission of space charge and the separation efficiency of photogenerated carriers, but also promotes the efficient production of H2O2 by 2e- oxygen reduction reaction. The introduction of Br- promotes O2 converted to triplet state and triggers energy transfer process to increase 1O2 production, O2 adsorption was facilitated through regulating the oxygen evolution (O2→1O2), which is beneficial to the subsequent oxygen reduction process. The results showed that the H2O2 yield of 0.05 K-CN catalyst reached 26.0 mmol g-1 h-1, which was more than 5 times that of pure g-C3N4.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2020
·
IF 6.146
Kai Chen,Suqin Ci,Qiuhua Xu,Pingwei Cai,Meizhen Li,Lijuan Xiang,Xi Hu,Zhenhai Wen
The application of electrocatalysts for the oxygen reduction reaction (ORR) is vital in a variety of energy conversion technologies. Exploring low-cost ORR catalysts with high activity and long-term stability is highly desirable, although it still remains challenging. Herein, we report a facile and reliable route to convert ZIF-8 modified by Fe-phenanthroline into Fe-incorporated and N-doped carbon dodecahedron nanoarchitecture (Fe-NCDNA), in which carbon nanosheets are formed in situ as the building blocks with uniform Fe-N-C species decoration. Systematic electrochemical studies demonstrate that the as-synthesized Fe-NCDNA electrocatalyst possesses highly attractive catalytic features toward the ORR in terms of activity and durability in both alkaline and neutral media. The Zn-air battery with the optimal Fe-NCDNA catalyst as the cathode performs impressively, delivering a power density of 184 mW cm –2 and a specific capacity of 801 mAh g –1 ; thus, it exhibits great competitive advantages over those of the Zn-air devices employing a Pt-based cathode electro catalyst.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2020
·
IF 0
Meiling Fan,Xiangchuan Pan,Weiran Lin,Haining Zhang
Nitrogen-doped carbon materials are realized as effective electrode materials for oxygen-involved electrochemical devices. Understanding of active sites for adsorption of oxygen molecules is of significant importance for the development of carbon-based electrode materials. Herein, we synthesize two model catalysts named carbon-covered nitrogen-doped hollow carbon nanoparticles and nitrogen-doped carbon-covered hollow carbon nanoparticles by pyrolysis of block copolymer brushes to investigate the active sites for the adsorption of oxygen molecules. The electrocatalytic performance for oxygen reduction reaction (ORR) and carbon dioxide adsorption suggest that carbon atoms are Lewis basic active sites for oxygen adsorption. The coverage of a thin carbon layer on nitrogen-doped carbon materials can increase the surface density of Lewis basic sites for oxygen adsorption and can accordingly improve the electrocatalytic activity toward ORR as confirmed by a positive shift of both onset potential and half-wave potential.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
JOURNAL OF POWER SOURCES
·
2019
·
IF 7.467
Qiulin Li,Heng Liu,Long-Cheng Zhang,Hao Chen,Hongjiu Zhu,Yuanke Wu,Maowen Xu,Shu-Juan Bao
Fe-N and pyridinic-N generally are considered the active sites of Fe-N-C catalyst. In this featured work, small uniform Fe/N-rich polymer spheres are selected to prepare the Fe-N-C catalyst and study how the sintering atmosphere (NH 3 , Ar, and H 2 ) to engineer their products. The findings reveal that the sintering atmosphere greatly affected not only the composition , aggregate state, and morphology of Fe, but also the graphitization degree and pore structure of carbon. In addition, XPS results suggest that Fe-N-C-NH 3 possesses the highest Fe-N and pyridinic-N content. Combining its abundant pores, high graphitization, and large specific surface area, the catalyst obtained in NH 3 atmosphere delivers best ORR catalytic performance (E 0 = 0.97 V, E 1/2 = 0.85 V vs RHE), which is even comparable to commercial Pt/C (E 0 = 0.97 V, E 1/2 = 0.83V vs RHE). Moreover, the catalyst exhibits greater stability and methanol resistance than those of Pt/C.
研究领域:
材料科学
·
电化学
✓ 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）