Abstract
Size- and shape-dependent electrochemical activity of nanostructures reveals relationships between nanostructure design and electrochemical performance. However, electrochemical performance of aspect-ratio-tunable quasi-two-dimensional (2D) nanomaterials with anisotropic properties has not been fully investigated. We prepared monodispersed hexagonal covellite (CuS) nanoplatelets (NPls) of fixed thickness (∼2 nm) but broadly tunable diameter (from 8 to >100 nm). These span a range of aspect ratios, from â4 to >50, connecting quasi-isotropic and quasi-2D regimes. Tests of electrochemical activity of the NPls for the oxygen reduction reaction in alkaline solution showed improved activity with increasing diameter. Combining experimental results with density functional theory calculations, we attribute size-dependent enhancement to anisotropy of conductivity and electrochemical activity. The lowest computed oxygen adsorption energy was on Cu sites exposed by cleaving covellite along (001) planes through tetrahedrally coordinated Cu atoms. The specific surface area of these planes, which are the top and bottom surfaces of the NPls, remains constant with changing diameter, for fixed NPl thickness. However, charge transport through the electrocatalyst film improves with increasing NPl diameter. These CuS NPl-carbon nanocatalysts provide inspiration for creating well-controlled layered nanomaterials for electrochemical applications and open up opportunities to design new electrocatalysts using transition-metal sulfides.
| Original language | English |
|---|---|
| Pages (from-to) | 42417-42426 |
| Number of pages | 10 |
| Journal | ACS Applied Materials and Interfaces |
| Volume | 10 |
| Issue number | 49 |
| DOIs | |
| Publication status | Published - Dec 12 2018 |
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Keywords
- 2D nanomaterials
- anisotropic electrocatalytic activity
- covellite copper sulfide
- DFT calculation
- facet sensitive electrochemical reaction
- oxygen reduction reaction
ASJC Scopus subject areas
- Materials Science(all)
Cite this
Synthesis and Anisotropic Electrocatalytic Activity of Covellite Nanoplatelets with Fixed Thickness and Tunable Diameter. / Liu, Yang; Zhang, Hanguang; Behara, Pavan Kumar; Wang, Xiaoyu; Zhu, Dewei; Ding, Shuo; Ganesh, Sai Prasad; Dupuis, Michel; Wu, Gang; Swihart, Mark T.
In: ACS Applied Materials and Interfaces, Vol. 10, No. 49, 12.12.2018, p. 42417-42426.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Synthesis and Anisotropic Electrocatalytic Activity of Covellite Nanoplatelets with Fixed Thickness and Tunable Diameter
AU - Liu, Yang
AU - Zhang, Hanguang
AU - Behara, Pavan Kumar
AU - Wang, Xiaoyu
AU - Zhu, Dewei
AU - Ding, Shuo
AU - Ganesh, Sai Prasad
AU - Dupuis, Michel
AU - Wu, Gang
AU - Swihart, Mark T.
PY - 2018/12/12
Y1 - 2018/12/12
N2 - Size- and shape-dependent electrochemical activity of nanostructures reveals relationships between nanostructure design and electrochemical performance. However, electrochemical performance of aspect-ratio-tunable quasi-two-dimensional (2D) nanomaterials with anisotropic properties has not been fully investigated. We prepared monodispersed hexagonal covellite (CuS) nanoplatelets (NPls) of fixed thickness (∼2 nm) but broadly tunable diameter (from 8 to >100 nm). These span a range of aspect ratios, from â4 to >50, connecting quasi-isotropic and quasi-2D regimes. Tests of electrochemical activity of the NPls for the oxygen reduction reaction in alkaline solution showed improved activity with increasing diameter. Combining experimental results with density functional theory calculations, we attribute size-dependent enhancement to anisotropy of conductivity and electrochemical activity. The lowest computed oxygen adsorption energy was on Cu sites exposed by cleaving covellite along (001) planes through tetrahedrally coordinated Cu atoms. The specific surface area of these planes, which are the top and bottom surfaces of the NPls, remains constant with changing diameter, for fixed NPl thickness. However, charge transport through the electrocatalyst film improves with increasing NPl diameter. These CuS NPl-carbon nanocatalysts provide inspiration for creating well-controlled layered nanomaterials for electrochemical applications and open up opportunities to design new electrocatalysts using transition-metal sulfides.
AB - Size- and shape-dependent electrochemical activity of nanostructures reveals relationships between nanostructure design and electrochemical performance. However, electrochemical performance of aspect-ratio-tunable quasi-two-dimensional (2D) nanomaterials with anisotropic properties has not been fully investigated. We prepared monodispersed hexagonal covellite (CuS) nanoplatelets (NPls) of fixed thickness (∼2 nm) but broadly tunable diameter (from 8 to >100 nm). These span a range of aspect ratios, from â4 to >50, connecting quasi-isotropic and quasi-2D regimes. Tests of electrochemical activity of the NPls for the oxygen reduction reaction in alkaline solution showed improved activity with increasing diameter. Combining experimental results with density functional theory calculations, we attribute size-dependent enhancement to anisotropy of conductivity and electrochemical activity. The lowest computed oxygen adsorption energy was on Cu sites exposed by cleaving covellite along (001) planes through tetrahedrally coordinated Cu atoms. The specific surface area of these planes, which are the top and bottom surfaces of the NPls, remains constant with changing diameter, for fixed NPl thickness. However, charge transport through the electrocatalyst film improves with increasing NPl diameter. These CuS NPl-carbon nanocatalysts provide inspiration for creating well-controlled layered nanomaterials for electrochemical applications and open up opportunities to design new electrocatalysts using transition-metal sulfides.
KW - 2D nanomaterials
KW - anisotropic electrocatalytic activity
KW - covellite copper sulfide
KW - DFT calculation
KW - facet sensitive electrochemical reaction
KW - oxygen reduction reaction
UR - http://www.scopus.com/inward/record.url?scp=85058338822&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85058338822&partnerID=8YFLogxK
U2 - 10.1021/acsami.8b15895
DO - 10.1021/acsami.8b15895
M3 - Article
C2 - 30451490
VL - 10
SP - 42417
EP - 42426
JO - ACS applied materials & interfaces
JF - ACS applied materials & interfaces
SN - 1944-8244
IS - 49
ER -