Title: Cations controlled growth of β-MnO₂ crystals with tunable facets for electrochemical energy storage

Abstract

Engineering crystal facets to enhance their functionalities often require complex processing routes to suppress the growth of surfaces with the lowest thermodynamic energies. Herein, we report a unique method to control the morphologies of β-MnO₂ crystals with different occupancy of {100}/{111} facets through the effect of K⁺ cations. Combining aberration-corrected scanning transmission electron microscopy (STEM), ultramicrotomy, and dynamic functional theory (DFT) simulation, we clarified that the β-MnO₂ crystals were formed through a direct solid-state phase transition process. Increasing the concentration of K⁺ cations in the precursor gradually changed the morphology of β-MnO₂ from bipyramid prism ({100}+{111} facets) to an octahedron structure ({111} facets). The K⁺ cations controlled the morphology of β-MnO₂ by affecting the formation of α-K_0.5Mn₄O₈ intermediate phase and the subsequent phase transition. Utilizing the β-MnO₂ crystals as the cathode for Li-ion batteries showed that highly exposed {111} facets offered β-MnO₂ crystal better rate performance, with ~70% capacity retention when the charge-discharge rate increased from 20 mA/g to 200 mA/g. Furthermore, our work revealed a new mechanism to tune the morphology of this earth-abundant metal oxide crystal, which could be used to adjust its electrochemical performance for different applications, such as supercapacitors and catalysts for metal-air batteries and fuelmore » cells.« less

Authors:

Yao, Wentao  ^[1];

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• Search DOE PAGES for ORCID "0000-0003-1653-769X"

Odegard, Gregory M. ^[1]; Huang, Zhennan ^[2]; Yuan, Yifei ^[3]; Asayesh-Ardakani, Hasti ^[4]; Sharifi-Asl, Soroosh ^[2]; Cheng, Meng ^[2]; Song, Boao ^[2]; Deivanayagam, Ramasubramonian  ^[2];

• Search DOE PAGES for author "Deivanayagam, Ramasubramonian"
• Search DOE PAGES for ORCID "0000-0003-1367-009X"

Long, Fei ^[1]; Friedrich, Craig R. ^[1]; Amine, Khalil  ^[5];

• Search DOE PAGES for author "Amine, Khalil"
• Search DOE PAGES for ORCID "0000-0001-9206-3719"

Lu, Jun  ^[6];

• Search DOE PAGES for author "Lu, Jun"
• Search DOE PAGES for ORCID "0000-0003-0858-8577"

Shahbazian-Yassar, Reza ^[4]

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+ Show Author Affiliations

1. Michigan Technological Univ., Houghton, MI (United States)
2. Univ. of Illinois at Chicago, Chicago, IL (United States)
3. Univ. of Illinois at Chicago, Chicago, IL (United States); Argonne National Lab. (ANL), Argonne, IL (United States)
4. Michigan Technological Univ., Houghton, MI (United States); Univ. of Illinois at Chicago, Chicago, IL (United States)
5. Argonne National Lab. (ANL), Argonne, IL (United States); Imam Abdulrahman Bin Faisal Univ., Dammam (Saudi Arabia)
6. Argonne National Lab. (ANL), Argonne, IL (United States)

Publication Date:

Thu Mar 22 00:00:00 EDT 2018

Research Org.:

Argonne National Lab. (ANL), Argonne, IL (United States)

Sponsoring Org.:

National Science Foundation (NSF); USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V); USDOE

OSTI Identifier:

1461337

Alternate Identifier(s):

OSTI ID: 1496462

Grant/Contract Number:  

AC02-06CH11357; 4J-30361; JEMARM200CF; JEM-ARM200CF

Resource Type:

Accepted Manuscript

Journal Name:

Nano Energy

Additional Journal Information:

Journal Volume: 48; Journal Issue: C; Journal ID: ISSN 2211-2855

Publisher:

Elsevier

Country of Publication:

United States

Language:

English

Subject:

25 ENERGY STORAGE; facet engineering; growth mechanism; hydrothermal synthesis; lithium-ion batteries; manganese dioxide