Abstract
The development of noble metal-free catalysts, which can replace noble metal ones, such as Pt, for various electrocatalytic processes in renewable energy devices is currently of huge interest. The β-phase of molybdenum carbide (i.e., β-Mo2C) has been reported to be one of the most active noble metal-free electrocatalysts for the hydrogen evolution reaction (HER) in electrolyzers, whereas the other phases, MoC and MoC1-x, have been widely regarded as weak electrocatalysts for HER. Herein, we report the synthesis of nanoporous substoichiometric α-MoC1-x and η-MoC nanosheets, named np-MoC NSs, that show comparable electrocatalytic activity toward HER as β-Mo2C does. The materials are synthesized using two-dimensional (2D) conjugated carbonitride and ammonium molybdate as precursors. Their structures contain N dopant atoms and nanopores. The pores create highly accessible catalytic sites and good mass and charge transport, and thereby excellent reaction kinetics for HER, in the materials. Theoretical calculations show that the N dopant atoms modulate the electronic properties of the catalytically active sites in the materials, leading to lower free energy of adsorption and desorption for the hydrogen species involved in the reaction and better catalytic activity for HER. This work demonstrates that, by simple structural design and electronic modulation, various phases of molybdenum carbides and related materials that have been traditionally considered inactive catalysts for HER can be made robust electrocatalysts for the reaction.
| Original language | English |
|---|---|
| Pages (from-to) | 18030-18038 |
| Number of pages | 9 |
| Journal | Journal of Materials Chemistry A |
| Volume | 7 |
| Issue number | 30 |
| DOIs | |
| Publication status | Published - Jan 1 2019 |
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ASJC Scopus subject areas
- Chemistry(all)
- Renewable Energy, Sustainability and the Environment
- Materials Science(all)
Cite this
Unconventional molybdenum carbide phases with high electrocatalytic activity for hydrogen evolution reaction. / Tang, Chaoyun; Zhang, Hui; Xu, Kuofeng; Zhang, Qianling; Liu, Jianhong; He, Chuanxin; Fan, Liangdong; Asefa, Teddy.
In: Journal of Materials Chemistry A, Vol. 7, No. 30, 01.01.2019, p. 18030-18038.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Unconventional molybdenum carbide phases with high electrocatalytic activity for hydrogen evolution reaction
AU - Tang, Chaoyun
AU - Zhang, Hui
AU - Xu, Kuofeng
AU - Zhang, Qianling
AU - Liu, Jianhong
AU - He, Chuanxin
AU - Fan, Liangdong
AU - Asefa, Teddy
PY - 2019/1/1
Y1 - 2019/1/1
N2 - The development of noble metal-free catalysts, which can replace noble metal ones, such as Pt, for various electrocatalytic processes in renewable energy devices is currently of huge interest. The β-phase of molybdenum carbide (i.e., β-Mo2C) has been reported to be one of the most active noble metal-free electrocatalysts for the hydrogen evolution reaction (HER) in electrolyzers, whereas the other phases, MoC and MoC1-x, have been widely regarded as weak electrocatalysts for HER. Herein, we report the synthesis of nanoporous substoichiometric α-MoC1-x and η-MoC nanosheets, named np-MoC NSs, that show comparable electrocatalytic activity toward HER as β-Mo2C does. The materials are synthesized using two-dimensional (2D) conjugated carbonitride and ammonium molybdate as precursors. Their structures contain N dopant atoms and nanopores. The pores create highly accessible catalytic sites and good mass and charge transport, and thereby excellent reaction kinetics for HER, in the materials. Theoretical calculations show that the N dopant atoms modulate the electronic properties of the catalytically active sites in the materials, leading to lower free energy of adsorption and desorption for the hydrogen species involved in the reaction and better catalytic activity for HER. This work demonstrates that, by simple structural design and electronic modulation, various phases of molybdenum carbides and related materials that have been traditionally considered inactive catalysts for HER can be made robust electrocatalysts for the reaction.
AB - The development of noble metal-free catalysts, which can replace noble metal ones, such as Pt, for various electrocatalytic processes in renewable energy devices is currently of huge interest. The β-phase of molybdenum carbide (i.e., β-Mo2C) has been reported to be one of the most active noble metal-free electrocatalysts for the hydrogen evolution reaction (HER) in electrolyzers, whereas the other phases, MoC and MoC1-x, have been widely regarded as weak electrocatalysts for HER. Herein, we report the synthesis of nanoporous substoichiometric α-MoC1-x and η-MoC nanosheets, named np-MoC NSs, that show comparable electrocatalytic activity toward HER as β-Mo2C does. The materials are synthesized using two-dimensional (2D) conjugated carbonitride and ammonium molybdate as precursors. Their structures contain N dopant atoms and nanopores. The pores create highly accessible catalytic sites and good mass and charge transport, and thereby excellent reaction kinetics for HER, in the materials. Theoretical calculations show that the N dopant atoms modulate the electronic properties of the catalytically active sites in the materials, leading to lower free energy of adsorption and desorption for the hydrogen species involved in the reaction and better catalytic activity for HER. This work demonstrates that, by simple structural design and electronic modulation, various phases of molybdenum carbides and related materials that have been traditionally considered inactive catalysts for HER can be made robust electrocatalysts for the reaction.
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U2 - 10.1039/c9ta04374h
DO - 10.1039/c9ta04374h
M3 - Article
VL - 7
SP - 18030
EP - 18038
JO - Journal of Materials Chemistry A
JF - Journal of Materials Chemistry A
SN - 2050-7488
IS - 30
ER -