Cyanogel-Derived Synthesis of Porous PdFe Nanohydrangeas as Electrocatalysts for Oxygen Reduction Reaction

It is important to develop cost-efficient electrocatalysts used in the oxygen reduction reaction (ORR) for widespread applications in fuel cells. Palladium (Pd) is a promising catalyst, due to its more abundant reserves and lower price than platinum (Pt), and doping an earth-abundant 3d-transition metal M into Pd to form Pd–M bimetallic alloys may not only further reduce the use of expensive Pd but also promote the electrocatalytic performance of ORR, owing to the synergistic effect between Pd and M. Here we report a cyanogel-derived synthesis of PdFe alloys with porous nanostructure via a simple coinstantaneous reduction reaction by using K2PdIICl4/K4FeII(CN)6 cyanogel as precursor. The synthesized PdFe alloys possess hydrangea-like morphology and porous nanostructure, which are beneficial to the electrochemical performance in ORR. The onset potential of the porous PdFe nanohydrangeas is determined to be 0.988 V, which is much more positive than that of commercial Pt/C catalyst (0.976 V) and Pd black catalyst (0.964 V). Resulting from the unique structural advantages and synergetic effect between bimetals, the synthesized PdFe nanohydrangeas with porous structure have outstanding electrocatalytic activity and stability for ORR, compared with the commercial Pd black and Pt/C.

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Fluorine-doped graphene with an outstanding electrocatalytic performance for efficient oxygen reduction reaction in alkaline solution

Royal Society Open Science ◽

10.1098/rsos.180925 ◽

2018 ◽

Vol 5 (10) ◽

pp. 180925 ◽

Cited By ~ 5

Author(s):

Jiahao Guo ◽

Jianguo Zhang ◽

Hanqing Zhao ◽

Yongshuang Fang ◽

Kun Ming ◽

...

Keyword(s):

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Carbon Materials ◽

Pyrolysis Temperature ◽

Low Cost ◽

Catalytic Performance ◽

Reduction Reaction ◽

Onset Potential ◽

Doped Graphene ◽

Cost Efficient

Doping carbon materials have proved to be the front runners to substitute for Pt as oxygen reduction reaction (ORR) catalysts. Fluorine-doped graphene (FG) has rarely been used as ORR catalyst because of the difficulty in preparation. Herein, we report FG sheets prepared by a thermal pyrolysis graphene oxide (GO) process in the presence of zinc fluoride (ZnF 2 ) as an efficient electrocatalyst for ORR in the alkaline medium. The results show that the pyrolysis temperature seriously affected the doped fluoride amount and morphology of catalyst. It is found that the FG-1100 catalyst possesses a more positive onset potential, higher current density and better four-electron process for ORR than other FG samples. FG-1100 displays an outstanding ORR catalytic activity that is comparable to that of the commercial Pt/C catalyst. Also, its durability and methanol tolerance ability are superior to those of the commercial Pt/C. The excellent ORR catalytic performance is closely related to its higher doped fluorine amount and wrinkle morphology. The FG catalyst can be developed as a low-cost, efficient and durable catalyst as a viable replacement for the Pt/C catalyst, promoting the commercialization of fuel cells.

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Synergistic effect between atomically dispersed Fe and Co metal sites for enhanced oxygen reduction reaction

Journal of Materials Chemistry A ◽

10.1039/c9ta12516g ◽

2020 ◽

Vol 8 (8) ◽

pp. 4369-4375 ◽

Cited By ~ 13

Author(s):

Lulu Chen ◽

Yelong Zhang ◽

Lile Dong ◽

Wenxiu Yang ◽

Xiangjian Liu ◽

...

Keyword(s):

Density Functional Theory ◽

Synergistic Effect ◽

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Density Functional ◽

Synergetic Effect ◽

Density Functional Theory Calculations ◽

Reduction Reaction ◽

Functional Theory ◽

Air Battery

Atomically dispersed Fe and Co on N-doped carbon were prepared as ORR and Zn–air battery catalysts, and the synergetic effect between Fe–N4 and Co–N4 was demonstrated by electrochemical results and density functional theory calculations.

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The synergetic effect of straining and N-doping in graphene for enhanced oxygen reduction reaction performance

Materials Express ◽

10.1166/mex.2020.1805 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1718-1724

Author(s):

Weiwei Liu ◽

Lijun Yuan ◽

Zhenhua Zhang ◽

Xuefeng Zhang ◽

Pengfei Guan ◽

...

Keyword(s):

Synergistic Effect ◽

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Synergistic Effects ◽

Synergetic Effect ◽

Reduction Reaction ◽

Atomic Scale ◽

N Doping ◽

Synergistic Mechanism ◽

Carbon Based

Carbon-based catalysts are engineered by either atomic-scale heteroatom doping or intrinsic structural tuning. However, their synergistic effects are yet to be well-understood. Herein, we report a theoretical investigation, based on first-principles simulations, devoted to the catalytic characteristics of graphene in an oxygen reduction reaction (ORR), where graphene is designed with different curvatures and doped with individual N atoms. We discover that the synergistic effect of straining and nitrogen doping (N-doping) can be more effective in improving the performance of ORR compared to N-doped graphene, strained graphene, and other graphenerelated structures. Such a synergistic effect can be attributed to the fact that N-doping reduces the bandgap, promotes electron mobility, and facilitates the transfer of electrons to O2, whereas straining enhances the electronic orbit coupling interaction between the substrate and the adsorbed O2. In the future, our study will have important implications in understanding the synergistic mechanism of straining and N-doping in graphene, and thus, designing novel carbon-based catalysts.

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Superior FexN electrocatalyst derived from 1,1′-diacetylferrocene for oxygen reduction reaction in alkaline and acidic media

Nanotechnology Reviews ◽

10.1515/ntrev-2020-0057 ◽

2020 ◽

Vol 9 (1) ◽

pp. 843-852

Author(s):

Hunan Jiang ◽

Jinyang Li ◽

Mengni Liang ◽

Hanpeng Deng ◽

Zuowan Zhou

Keyword(s):

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Current Density ◽

Active Sites ◽

Reduction Reaction ◽

Alkaline Media ◽

Acidic Media ◽

Onset Potential ◽

Acidic And Alkaline Media ◽

The Stability

AbstractAlthough Fe–N/C catalysts have received increasing attention in recent years for oxygen reduction reaction (ORR), it is still challenging to precisely control the active sites during the preparation. Herein, we report FexN@RGO catalysts with the size of 2–6 nm derived from the pyrolysis of graphene oxide and 1,1′-diacetylferrocene as C and Fe precursors under the NH3/Ar atmosphere as N source. The 1,1′-diacetylferrocene transforms to Fe3O4 at 600°C and transforms to Fe3N and Fe2N at 700°C and 800°C, respectively. The as-prepared FexN@RGO catalysts exhibited superior electrocatalytic activities in acidic and alkaline media compared with the commercial 10% Pt/C, in terms of electrochemical surface area, onset potential, half-wave potential, number of electrons transferred, kinetic current density, and exchange current density. In addition, the stability of FGN-8 also outperformed commercial 10% Pt/C after 10000 cycles, which demonstrates the as-prepared FexN@RGO as durable and active ORR catalysts in acidic media.

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Methanol-Tolerant Oxygen Reduction Reaction at Pt–Pd/C Alloy Nanocatalysts

Journal of Fuel Cell Science and Technology ◽

10.1115/1.4001759 ◽

2010 ◽

Vol 8 (1) ◽

Cited By ~ 9

Author(s):

A. Mary Remona ◽

K. L. N. Phani

Keyword(s):

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Rotating Disk ◽

Reduction Reaction ◽

Rotating Disk Electrode ◽

Methanol Tolerance ◽

Pd Catalysts ◽

Onset Potential ◽

Direct Methanol ◽

Methanol Tolerant

Carbon-supported platinum and Pt–Pd alloy electrocatalysts with different Pt/Pd atomic ratios were synthesized by a microemulsion method at room temperature (metal loading is 10 wt %). The Pt–Pd/C bimetallic catalysts showed a single-phase fcc structure and the mean particle size of Pt–Pd/C catalysts was found to be lower than that of Pt/C. The methanol-tolerant studies of the catalysts were carried out by activity evaluation of oxygen reduction reaction (ORR) on Pt–Pd catalysts using a rotating disk electrode (RDE). The studies indicated that the order of methanol tolerance was found to be PtPd3/C>PtPd/C>Pt3Pd/C. The oxygen reduction activities of all Pt–Pd/C were considerably larger than that of Pt/C with respect to onset and overpotential values. The Pd-loaded catalysts shift the onset potential of ORR by 125 mVMSE, 53 mVMSE, and 41 mVMSE to less cathodic potentials for Pt3Pd/C, PtPd/C, and PtPd3/C, respectively, with reference to Pt/C and the Pt3Pd/C catalyst showed greater shift in the onset value than the other PtPd catalysts reported in literature. Moreover, the Pt–Pd/C catalysts exhibited much higher methanol tolerance during ORR than the Pt/C, assessing that these catalysts may function as a methanol-tolerant cathode catalysts in a direct methanol fuel cell.

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Interplay between morphology and electrochemical performance of “core–shell” electrocatalysts for oxygen reduction reaction based on a PtNix carbon nitride “shell” and a pyrolyzed polyketone nanoball “core”

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2013.08.053 ◽

2014 ◽

Vol 39 (6) ◽

pp. 2828-2841 ◽

Cited By ~ 52

Author(s):

E. Negro ◽

S. Polizzi ◽

K. Vezzù ◽

L. Toniolo ◽

G. Cavinato ◽

...

Keyword(s):

Electrochemical Performance ◽

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Carbon Nitride ◽

Reduction Reaction ◽

Core Shell

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The Synergistic Effect of Carbon Edges and Dopants Towards Efficient Oxygen Reduction Reaction

Journal of Colloid and Interface Science ◽

10.1016/j.jcis.2021.11.069 ◽

2021 ◽

Author(s):

Tingting Xiang ◽

Zirui Wu ◽

Zhongti Sun ◽

Chao Cheng ◽

Wenlong Wang ◽

...

Keyword(s):

Synergistic Effect ◽

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Reduction Reaction

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The synthesis of Fe/N–C@CNFs and its electrochemical performance toward oxygen reduction reaction

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2020.08.213 ◽

2020 ◽

Vol 45 (56) ◽

pp. 31892-31901 ◽

Cited By ~ 1

Author(s):

Min Sun ◽

Zijiong Li ◽

Yanyue Liu ◽

Dongfang Guo ◽

Zhiyong Xie ◽

...

Keyword(s):

Electrochemical Performance ◽

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Reduction Reaction

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MOF-Derived CuPt/NC Electrocatalyst for Oxygen Reduction Reaction

Catalysts ◽

10.3390/catal10070799 ◽

2020 ◽

Vol 10 (7) ◽

pp. 799 ◽

Cited By ~ 1

Author(s):

Rehan Anwar ◽

Naseem Iqbal ◽

Saadia Hanif ◽

Tayyaba Noor ◽

Xuan Shi ◽

...

Keyword(s):

Electron Microscopy ◽

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Photoelectron Spectroscopy ◽

Rotating Disk ◽

Reduction Reaction ◽

Rotating Disk Electrode ◽

X Ray ◽

Onset Potential ◽

Orr Activity

Metal-organic frameworks (MOFs) have been at the center stage of material science in the recent past because of their structural properties and wide applications in catalysis. MOFs have also been used as hard templates for the preparation of catalysts. In this study, highly active CuPt/NC electrocatalyst was synthesized by pyrolyzing Cu-tpa MOF along with Pt precursor under flowing Ar-H2 atmosphere. The catalyst was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and X-ray powder diffraction (XRD). Rotating disk electrode study was performed to determine the oxygen reduction reaction (ORR) activity for CuPt/NC in 0.1 M HClO4 at different revolutions per minute (400, 800, 1200, and 1600) and it was also compared with commercial Pt/C catalyst. Further the ORR performance was evaluated by K-L plots and Tafel slope. CuPt/NC shows excellent ORR performance with onset potential of 0.9 V (vs. RHE), which is comparable with commercial Pt/C. The ORR activity of CuPt/NC is demonstrated as an efficient electrocatalyst for fuel cell.

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