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Highly efficient electroreduction of CO2 by defect single-atomic Ni-N3 sites anchored on ordered micro-macroporous carbons.
- Source :
- SCIENCE CHINA Chemistry; Aug2022, Vol. 65 Issue 8, p1584-1593, 10p
- Publication Year :
- 2022
-
Abstract
- Microporous supports typically fail to fully expose active sites for electrolytes and CO<subscript>2</subscript> molecules, and this usually results in low current density for the electrocatalytic CO<subscript>2</subscript> reduction reaction (CO<subscript>2</subscript>RR). To overcome the biggest obstacle and facilitate commercial applications, defective single-atomic Ni-N<subscript>3</subscript> sites anchored to ordered micro-macroporous N-doped carbon (Ni-N/OMC) have been prepared by the pyrolysis of the Ni-ZIF-8@PS (ZIF = zeolitic imidazolate framework) and are intended to provide enhanced CO<subscript>2</subscript>RR with a current density at an industrial level. This Ni-ZIF-8@PS is constructed of nickel-based ZIF-8 embedded in the three-dimensional (3D) highly ordered polystyrene spheres (PS). The 3D ordered micro-macroporous architecture of Ni-N/OMC could facilitate the mass transfer of substrates to the accessible defective single-atomic Ni-N<subscript>3</subscript> sites through micropores (0.6 nm) and macropores (∼200 nm) interconnected by 50 nm channels. In a flow cell, Ni-N/OMC exhibits almost 100.0% CO Faraday efficiency (FE<subscript>CO</subscript>) between −0.2 and −1.1 V vs. RHE and an industrial level CO partial current density of 208 mA cm<superscript>−2</superscript>. It has a turnover frequency of 1.5×10<superscript>5</superscript> h<superscript>−1</superscript> at −1.1 V vs. RHE in 1 M KOH electrolyte, which exceeds that of most reported nickel-based electrocatalysts. This excellent CO<subscript>2</subscript>RR performance for Ni-N/OMC makes it a state-of-the-art electrocatalyst for CO<subscript>2</subscript>RR. Theoretical calculations show that the defective Ni-N<subscript>3</subscript> site can lower the energy of *COOH formation compared with that of the Ni-N<subscript>4</subscript> site, thereby accelerating CO<subscript>2</subscript>RR. Ni-N/OMC can also be utilized as a cathodic catalyst in Zn-CO<subscript>2</subscript> battery, exhibiting high CO selectivity in the discharge process and excellent stability. This work paves a pathway to rational design of highly efficient electrocatalysts with 3D hierarchically ordered micro-macroporous architecture for CO<subscript>2</subscript>RR towards industrial production and commercial applications. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 16747291
- Volume :
- 65
- Issue :
- 8
- Database :
- Complementary Index
- Journal :
- SCIENCE CHINA Chemistry
- Publication Type :
- Academic Journal
- Accession number :
- 158335489
- Full Text :
- https://doi.org/10.1007/s11426-022-1263-5