MnO<sub>2</sub>-Based Nanostructures as Catalysts for Electrochemical Oxygen Reduction in Alkaline Media

Cheng, Fangyi; Su, Yi; Liang, Jing; Tao, Zhanliang; Chen, Jun

doi:10.1021/cm901698s

Cited by 706 publications

(523 citation statements)

References 49 publications

Supporting

Mentioning

499

Contrasting

Unclassified

Order By: Relevance

“…Non-noble nanocatalysts, including transition metal chalcogenides, 6 nitrides, 7,8 oxides 9 and heteroatom-doped carbonaceous (e.g. graphite, carbon nanotubes, graphene and graphene oxides), 10 have been recently identified for highly catalyzing the ORR.…”

Section: Introductionmentioning

confidence: 99%

Graphene-based transition metal oxide nanocomposites for the oxygen reduction reaction

et al. 2015

View full text Add to dashboard Cite

The development of low cost, durable and efficient nanocatalysts to substitute expensive and rare noble metals (e.g. Pt, Au and Pd) in overcoming the sluggish kinetic process of the oxygen reduction reaction (ORR) is essential to satisfy the demand for sustainable energy conversion and storage in the future. Graphene based transition metal oxide nanocomposites have extensively been proven to be a type of promising highly efficient and economic nanocatalyst for optimizing the ORR to solve the world-wide energy crisis. Synthesized nanocomposites exhibit synergetic advantages and avoid the respective disadvantages.In this feature article, we concentrate on the recent leading works of different categories of introduced transition metal oxides on graphene: from the commonly-used classes (FeO x , MnO x , and CoO x ) to some rare and heat-studied issues (TiO x , NiCoO x and Co-MnO x ). Moreover, the morphologies of the supported oxides on graphene with various dimensional nanostructures, such as one dimensional nanocrystals, two dimensional nanosheets/nanoplates and some special multidimensional frameworks are further reviewed.The strategies used to synthesize and characterize these well-designed nanocomposites and their superior properties for the ORR compared to the traditional catalysts are carefully summarized. This work aims to highlight the meaning of the multiphase establishment of graphene-based transition metal oxide nanocomposites and its structural-dependent ORR performance and mechanisms.

show abstract

Section: Introductionmentioning

confidence: 99%

Graphene-based transition metal oxide nanocomposites for the oxygen reduction reaction

et al. 2015

View full text Add to dashboard Cite

show abstract

“…The presence of redox waves during the charge/discharge process was already reported for several MnO 2 -based electrodes (Hu & Tsou, 2002;Brousse et al, 2006;Ghodbane & Favier 2009;Chang et al, 2009;Lee et al, 2010). The electrochemical experiments in their work demonstrate that the crystallographic form of MnO 2 influences the electrochemical performance, and the small tunnel of -MnO 2 was not suitable to store cations, while the large tunnel size of -MnO 2 favors the storage of cations Cheng et al, 2010). In addition, the presence of other metal cations in the tunnel in advance hinders the diffusion and storage of the electrolyte cations leading to a decrease in capacitance.…”

Section: +-2mentioning

confidence: 66%

Nanostructured MnO2 for Electrochemical Capacitor

Xu¹,

Bao²

2011

Energy Storage in the Emerging Era of Smart Grids

View full text Add to dashboard Cite

“…The efficiency of Li-air batteries, to some extent, is limited by the slow kinetics of the oxygen reduction reaction (ORR) and the OER (22,(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43). To assess their ORR and OER catalytic activity, our materials were first loaded (with the same mass loading) onto glassy carbon electrodes.…”

Section: Resultsmentioning

confidence: 99%

Hierarchical mesoporous perovskite La ₀ _.5 Sr _0.5 CoO _2.91 nanowires with ultrahigh capacity for Li-air batteries

Zhao

Mai

et al. 2012

Proc. Natl. Acad. Sci. U.S.A.

321

147

View full text Add to dashboard Cite

Lithium-air batteries have captured worldwide attention due to their highest energy density among the chemical batteries. To provide continuous oxygen channels, here, we synthesized hierarchical mesoporous perovskite La 0.5 Sr 0.5 CoO 2.91 (LSCO) nanowires. We tested the intrinsic oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activity in both aqueous electrolytes and nonaqueous electrolytes via rotating disk electrode (RDE) measurements and demonstrated that the hierarchical mesoporous LSCO nanowires are high-performance catalysts for the ORR with low peak-up potential and high limiting diffusion current. Furthermore, we fabricated Li-air batteries on the basis of hierarchical mesoporous LSCO nanowires and nonaqueous electrolytes, which exhibited ultrahigh capacity, ca. over 11,000 mAh·g -1 , one order of magnitude higher than that of LSCO nanoparticles. Besides, the possible reaction mechanism is proposed to explain the catalytic activity of the LSCO mesoporous nanowire. electrocatalysis | energy storage W ith the growth of energy demand, searching for new clean energy sources to replace conventional fuel energy has been a challenge today (1-6). Li-ion batteries have developed rapidly in recent years because of their low cost, long cycle life, good reversibility, and no memory effect. However, even when it was fully developed, the highest energy storage of Li-ion batteries is insufficient to satisfy the ever-increasing requirements for batteries with high capacities (7,8). Recently, Li-air batteries have attracted great interest because they potentially have much higher gravimetric energy storage density compared with all other chemical batteries (9-18). They could theoretically offer very high specific energies (i.e., 5,000 Wh·kg −1 ) because oxygen, the cathode active material, is not stored in the battery, but can be accessed from the environment. Thus, Li-air batteries are eco-friendly electrochemical power sources.However, there are some challenges in Li-air battery research. In an aprotic electrolyte, the fundamental cathode discharge reactions are thought to be 2Li + O 2 → Li 2 O 2 and 2Li + 0.5O 2 → Li 2 O. Recent studies demonstrated the degradation of the electrolyte (19,20), and the precipitation of reaction products Li 2 O 2 / Li 2 O or electrolyte decomposition products on the catalyst and electrode eventually blocked the oxygen pathway and limited the capacity of the Li-air batteries.To enhance the performance, it has been suggested that one method for enhancing the mobility of oxygen ions is to provide disorder-free channels of oxygen vacancies, using compounds with the perovskite structure that exhibits cation ordering (21,22). It is well known that perovskite materials have wide applications in catalysis for fuel cells and metal-air batteries due to their defective structures and excellent oxygen mobility. Shao-Horn and coworkers have deeply studied perovskite oxides for oxygen evolution reaction (OER) catalysis and found that Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3-x and La 0.5 C...

show abstract

MnO₂-Based Nanostructures as Catalysts for Electrochemical Oxygen Reduction in Alkaline Media

Cited by 706 publications

References 49 publications

Graphene-based transition metal oxide nanocomposites for the oxygen reduction reaction

Graphene-based transition metal oxide nanocomposites for the oxygen reduction reaction

Nanostructured MnO2 for Electrochemical Capacitor

Hierarchical mesoporous perovskite La ₀ _.5 Sr _0.5 CoO _2.91 nanowires with ultrahigh capacity for Li-air batteries

Contact Info

Product

Resources

About

MnO2-Based Nanostructures as Catalysts for Electrochemical Oxygen Reduction in Alkaline Media

Cited by 706 publications

References 49 publications

Graphene-based transition metal oxide nanocomposites for the oxygen reduction reaction

Graphene-based transition metal oxide nanocomposites for the oxygen reduction reaction

Nanostructured MnO2 for Electrochemical Capacitor

Hierarchical mesoporous perovskite La 0 .5 Sr 0.5 CoO 2.91 nanowires with ultrahigh capacity for Li-air batteries

Contact Info

Product

Resources

About

MnO₂-Based Nanostructures as Catalysts for Electrochemical Oxygen Reduction in Alkaline Media

Hierarchical mesoporous perovskite La ₀ _.5 Sr _0.5 CoO _2.91 nanowires with ultrahigh capacity for Li-air batteries