ACS Applied Materials & Interfaces
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2016
·
IF 7.145
Likai Wang,Zhenghua Tang,Wei Yan,Hongyu Yang,Qiannan Wang,Shaowei Chen
Porous carbon-supported gold nanoparticles of varied sizes were prepared using thiolate-capped molecular Au25, Au38, and Au144 nanoclusters as precursors. The organic capping ligands were removed by pyrolysis at controlled temperatures, resulting in good dispersion of gold nanoparticles within the porous carbons, although the nanoparticle sizes were somewhat larger than those of the respective nanocluster precursors. The resulting nanocomposites displayed apparent activity in the electroreduction of oxygen in alkaline solutions, which increased with decreasing nanoparticle dimensions. Among the series of samples tested, the nanocomposite prepared with Au25 nanoclusters displayed the best activity, as manifested by the positive onset potential at +0.95 V vs RHE, remarkable sustainable stability, and high numbers of electron transfer at (3.60–3.92) at potentials from +0.50 to +0.80 V. The performance is comparable to that of commercial 20 wt % Pt/C. The results demonstrated the unique feasibility of porous carbon-supported gold nanoparticles as high-efficiency ORR catalysts.
研究领域:
材料科学
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电化学
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DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Shan Wang,Laifei Xiong,Jinglei Bi,Xiaojing Zhang,Guang Yang,Shengchun Yang
The enhancement in the catalytic activity of PtM (transition metals, TMs) alloy nanoparticles (NPs) results from the electronic structure of Pt being modified by the TM. However, the oxidation of the TM would lead to the electronegativity difference between Pt and TM being much lowered, which induces a decrease in the number of electrons transferred from the TM to Pt, resulting in excessive oxygenated species accumulating on the surface of Pt, thus deteriorating their performance. In this work, the oxygen reduction reaction (ORR) performance of PtNi (Pt68Ni32) concave octahedral NPs (CONPs) in alkaline electrolytes is much improved by doping small amounts of phosphorus. The P-doped PtNi CONPs (P-PtNi) show about 2 and 10 times enhancement for ORR compared to PtNi and commercial Pt/C catalysts. The high-angle annular dark-field scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy mapping characterizations reveal that the P dopant uniformly distributes throughout the CONPs, Pt mainly locates at the edges and corners, whereas Ni situates at the center, forming a P-doped Pt-frame@Ni quasi-core–shell CONP. The X-ray photoelectron spectroscopy spectra indicate that the P dopant obviously increases the electron density of Pt compared with that of PtNi NPs, which contributes to the stabilization of the electronic structure of PtNi CONPs, thus restraining the excessive HO2– species produced on the catalysts, which endow them with a high catalytic performance in the ORR. In addition, the P attached to the Ni sites in the PtNi NPs partially prevents the Ni atoms being oxidized by the external O species, which is conducive to the structural and electrochemical stability of the PtNi NPs during the ORR. The present results provide a new insight into the development of ORR catalysts with low utilization of Pt.
研究领域:
材料科学
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电化学
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DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2015
·Vol. 3
·期 43
·21805-21814
·
IF 7.443
Yangming Lin,Yansong Zhu,Bingsen Zhang,Yoong Ahm Kim,Morinobu Endo,Dang Sheng Su
Incorporating heteroatoms into onion-like carbon (OLC, average size ∼5 nm) with a fullerene-like structure and investigating its peculiar properties are fascinating challenges. Here, we present straightforward fabrication of doped OLC samples with a high concentration of boron (0.63–4.57 at%) via a high-temperature thermal diffusion method. The highest proportion of substitutional boron of the boron species reaches 29%, which far exceeds most of the reported boron-doped carbon materials. The influence of boron on the fullerene-like layers and electronic properties of OLC is systematically investigated using Raman spectroscopy with different excitation energies (1.58–3.8 eV) and ultraviolet photoelectron spectroscopy (UPS). The as-prepared boron-doped OLC samples exhibit a perfect four-electron process for the oxygen reduction reaction (ORR), which is similar to commercial Pt/C. It is worth noting that the intrinsic relationship between the electronic properties and catalytic performance of doped samples is explored based on experimental studies instead of theoretical calculations. The results indicate that the lower work function, lower valence band edge and higher density of states (DOSs) of doped OLC are crucial to improve the catalytic performance. Our work can provide valuable information on the design of doped metal-free materials and give new evidence for enhanced ORR activity associated with heteroatom doping and electronic properties.
研究领域:
材料科学
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电化学
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DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 125
·103421-103427
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IF 3.84
Likai Wang,Zhenghua Tang,Xiaojun Liu,Wenhan Niu,Kai Zhou,Hongyu Yang,Weijia Zhou,Ligui Li,Shaowei Chen
Unlike bulk gold, gold nanoparticles (AuNPs) have been found to exhibit apparent electrocatalytic activity for oxygen reduction reaction (ORR). In this work, glutathione-capped AuNPs of ca. 4 nm in diameter were prepared by a wet chemical method and embedded into a mesoporous carbon matrix synthesized by using an SBA-15 amorphous silica template. Pyrolysis at elevated temperatures led to removal of the organic capping ligands and the formation of ordered mesoporous carbons loaded with a selected amount of AuNPs which exhibited no apparent agglomeration. The obtained nanocomposites exhibited apparent ORR activity in alkaline media, and the sample with 20 wt% AuNPs stood out as the best among the series, within the context of onset potential, kinetic current density and stability, in comparison with AuNPs alone, ordered mesoporous carbons, and commercial Pt/C catalysts. The remarkable performance was ascribed to the intimate interactions between the AuNPs and mesoporous carbons that facilitated fast electron transfer and rapid mass transport. This is the first time that ordered mesoporous carbons were employed to support AuNPs as ORR catalysts. The strategy may be exploited to prepare a wide range of electrocatalysts based on mesoporous carbons-supported metal nanoparticles with extraordinary reactivity and enhanced stability for ORR.
研究领域:
材料科学
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电化学
✓ 已验证
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DOI
高影响因子
Small
·
2016
·Vol. 12
·期 10
·1295-1301
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IF 8.315
Long Liu,Xianfeng Yang,Na Ma,Haitao Liu,Yanzhi Xia,Chengmeng Chen,Dongjiang Yang,Xiangdong Yao
Graphical A simple and scalable synthesis of a 3D Fe 2 N-based nanoaerogel is reported with superior oxygen reduction reaction activity from waste seaweed biomass, addressed the growing energy scarcity. The merits are due to the synergistic effect of the 3D porous hybrid aerogel support with excellent electrical conductivity, convenient mass transport and O 2 adsorption, and core/shell structured Fe 2 N/N-doped amorphous carbon nanoparticles.
研究领域:
能源材料科学
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环境科学
·
纳米技术
✓ 已验证
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DOI
PubMed
高影响因子
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
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2017
·Vol. 21
·期 6
·1639-1651
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IF 2.316
He Hongyun,Wang Min,Zhang Yan,Zhao Jinsheng
A novel composite formed between nitrogen-rich soluble conjugated polymer and carbon was prepared and evaluated as a candidate for oxygen reduction reaction (ORR) catalyst, and the composite was designated as PBBDP/C. The complexation between copper ion (II) and PBBDP/C formed another catalyst, named Cu-PBBDP/C. Electrochemical tests including cyclic voltammetry (CV), linear sweep voltammetry (LSV), and rotating ring disk electrode (RRDE) were used for the characterization of the ORR activities of the catalysts. The measurements showed that both of the catalysts showed considerable stability and apparent ORR activities, and the ORR activity of Cu-PBBDP/C was much higher than that of PBBDP/C. For digging into the exact ORR mechanisms, the rate constants of possible ORR pathways were calculated as analyzed for both catalysts. For PBBDP/C catalyst, the result indicated that oxygen was reduced through two parallel routes, the four-electron pathway and the two-electron pathway taking H 2 O 2 as the intermediate product. For Cu-PBBDP/C catalyst, the ORR was via a four-electron transfer-dominant process. In this case, the Cu-N
x
group is active sites for the direct reduction of oxygen to water.
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
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2017
·
IF 4.233
Wenbei Zhang,Tianlu Cui,Lingyun Yang,Chao Zhang,Ming Cai,Sai Sun,Yefeng Yao,Xiaodong Zhuang,Fan Zhang
Iron and nitrogen (Fe/N) co-doped porous carbons have already shown great potential as electrocatalysts for oxygen reduction reaction in alkaline media. However, it still remains a great challenge to finely integrate a hierarchical porous structure and Fe/N co-doping effect into one material at the same time. In this work, a rational design toward Fe/N-codoped hierarchical porous carbon spheres was developed by the formation of an iron-porphyrin-containing conjugated microporous polymer sphere with hollow structure (HCMP) through a silica sphere template directed condensation of pyrrole and 1,4-phthalaldehyde, then etched with NaOH, and treated with FeCl 2 . The resulting HCMP-Fe polymer was readily converted to a series of Fe/N co-doped hierarchical porous carbons (HPC-Fe/N-X, X = 700–900) upon pyrolysis at different temperatures and etching treatment. These porous carbons exhibit the high specific surface areas up to 518 m 2 g −1 and the contents of N and Fe up to 3.28 at.% and 0.85 wt.%, respectively. Benefiting from the high surface area, Fe/N co-doping character, HPC-Fe/N-700 exhibited excellent electrochemical catalytic performance for oxygen reduction reaction under alkaline condition (0.1 M KOH) with a low half-wave potential (0.84 V), a dominant four-electron transfer mechanism (n = 3.89 at 0.65 V), as well as a high diffusion limiting current density ( J L = 5.19 mA cm −2 ), comparable to those porous carbon-based ORR catalysts with excellent electrochemical performance.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2017
·
IF 3.582
Yingjie Chen,Shiben Liu,Liyan Yu,Qiuhong Liu,Yongtao Wang,Lifeng Dong
Nanoparticles with core–shell or hollow interiors have immense potential for catalysis. Herein, Ag@M x Fe 3− x O 4 (M = Co, Mn) core–shell nanoparticles were firstly synthesized through a seed-mediated method. These particles were then loaded onto carbon catalyst supports to form Ag@M x Fe 3− x O 4 /C. Then, hollow-M x Fe 3− x O 4 /C was prepared with the diffusion of Ag from Ag@M x Fe 3− x O 4 /C in saturated NaCl solution at room temperature . As a result, Ag@MnFe 2 O 4 /C demonstrates better oxygen reduction reaction (ORR) activity than Ag@CoFe 2 O 4 /C and other Ag@Mn x Fe 3− x O 4 /C with various Mn/Fe ratios. Moreover, Ag@MFe 2 O 4 /C shows superior ORR catalytic activities over hollow-MFe 2 O 4 /C, which can be due to electronic coupling between Ag core and MFe 2 O 4 shell. Furthermore, Ag@MnFe 2 O 4 /C catalysts demonstrate high durability for the ORR in alkaline media and insensitivity to methanol. These findings will provide helpful guidance for design and fabrication of carbon-supported core–shell catalysts for ORR in the future.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2021
·
IF 5.816
Fengxian Zhang,Ye Chen,Yang Liu,Xupo Liu,Shuyan Gao
Constructing highly efficient and durable non-noble metal modified carbon catalysts for oxygen reduction reaction (ORR) in the whole pH range is essential for energy conversion devices but still remains a challenge. Herein, the Fe/Fe 3 C nanoparticles and Fe-N X species anchored on the interconnected mesoporous carbon materials are fabricated through an economical and facile template-assisted polymerization-pyrolysis strategy. The catalyst exhibits unique features with the electronic interaction between Fe/Fe 3 C and Fe−N X , large specific surface area and high mesoporous structure as well as nitrogen doping in porous carbon skeletons, which can effectively catalyze ORR over the full pH range. In an alkaline electrolyte , the optimized catalyst displays favorable ORR performance with positive onset potential ( E onset = 0.91 V), half-wave potential ( E 1/2 = 0.83 V), long-term cycles stability and methanol tolerance, exceeding those for the commercial Pt/C. Furthermore, the prepared catalyst could be directly assembled into the alkaline Zn−air battery that exhibits the open-circuit voltage of 1.44 V, high power density of 96.0 mW cm −2 and long-term durability. Therefore, the template-assisted polymerization-pyrolysis strategy provides a promising route for designing high-performance non-noble metal decorated ORR electrocatalysts .
研究领域:
材料科学
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电化学
·
能源转换技术
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DOI
高影响因子
CRYSTENGCOMM
·
2018
·Vol. 21
·期 2
·290-296
·
IF 3.304
Sai Luo,Min Tang,Xingqiao Wu,Yang Ou,Zeyi Wang,Ni Jian,Xiao Li,Yangfan Lin,Yucong Yan,Jingbo Huang,Hui Zhang,Deren Yang
Pd is generally regarded as an alternative catalyst material to Pt for the oxygen reduction reaction (ORR). However, its catalytic activity and durability are much lower than those of Pt. Here, we report a facile approach for the synthesis of intermetallic Pd3Pb square nanoplates enclosed by {100} facets. The use of oleylamine (OAm), oleic acid (OA), and 1-octadecene (ODE) played important roles in the formation of the Pd3Pb intermetallic square nanoplates in high-quality. The Pd3Pb square nanoplates exhibited substantially enhanced ORR properties in terms of activity and durability. In particular, such nanoplates showed higher mass activity (0.62 mA μgPd−1) and specific activity (3.59 mA cm−2), which were 10.3 and 32.6 times higher than those of the commercial Pt/C, respectively, due to ligand and geometry effects. Significantly, the Pd3Pb square nanoplates/C were highly stable with 23% loss in specific activity and 21% loss in mass activity after 10 000 cycles compared to the Pd3Pb alloy dendritic nanocrystals/C (over 50% loss in specific and mass activities) due to their unique intermetallic structure with high chemical stability.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2020
·
IF 7.888
Lian-Hua Xu,Sheng-Li Zhang,Shi-Ying Guo,Xue-Ji Zhang,Serge Cosnier,Robert S. Marks,Wen-Ju Wang,Hai-Bo Zeng,Dan Shan
Rational design and facile synthesis of highly active electrocatalysts with low cost for oxygen reduction reaction (ORR) are always of great challenge. Specifically, development of a new type of energy-saving materials with convenient method is regarded as the current bottleneck. Herein, an innovative strategy based on amino trimethylene phosphonic acid (ATMP) as chelating agent for cobalt-metaphosphate coordination polymer is reported to one-pot synthesis of a novel precursor in methanol for ORR electrocatalyst. Carbonization of the precursor at 900 °C at N 2 atmosphere results in the feasible formation of cobalt metaphosphate based composite (Co(PO 3 ) 2 /NC). A further step in the thermal cleavage at 650 °C at air for 4 h, Co(PO 3 ) 2 /NC can be finally transformed into inorganic Co(PO 3 ) 2 . Advanced spectroscopic techniques and density function theory (DFT) calculations are applied to confirm the main catalytically active center and the physical properties of Co(PO 3 ) 2 /NC. This obtained Co(PO 3 ) 2 /NC nanocomposite exhibits superior electrocatalysis to Co(PO 3 ) 2 with an enhanced onset potential (0.906 V vs. RHE) and diffusion limiting current (5.062 mA cm −2 ), which are roughly close to those of commercial 20% Pt/C (0.916 V, 5.200 mA cm −2 ).
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
iScience
·
2022
·
IF 6.107
Tao Chen,Fanghua Ning,Jizhen Qi,Guang Feng,Yucheng Wang,Jin Song,Tonghuan Yang,Xi Liu,Liwei Chen,Dingguo Xia
Summary Searching for an efficient, durable, and low cost catalyst toward oxygen reduction reaction (ORR) is of paramount importance for the application of fuel cell technology. Herein, PtFeCoNiCu high-entropy alloy nanoparticles (PFCNC-HEA) is reported as electrocatalyst toward ORR. It shows remarkable ORR catalytic mass activity of 1.738 A mg −1 Pt at 0.90 V, which is 15.8 times higher than that of the state-of-art commercial Pt/C catalyst. It also exhibits outstanding stability with negligible voltage decay (3 mV) after 10k cycles accelerated durability test. High ORR activity is ascribed to the ligand effect caused by polymetallic elements, the optimization of the surface electronic structure, and the formation of multiple active sites on the surface. In the proton exchange membrane fuel cell setup, this cell delivers a power density of up to 1.380 W cm −2 with a cathodic Pt loading of 0.03 mg Pt cm −2 , demonstrating a promising catalyst design direction for highly efficient ORR.
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
危险品化学品经营许可证（带存储）