1. Universal Descriptor for Large-Scale Screening of High-Performance MXene-Based Materials for Energy Storage and Conversion
- Author
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Xiaolong Zou, Jia Li, Hongda Du, Chengjun Xu, Wenhui Duan, Feiyu Kang, Wei Jiang, and Lin Gan
- Subjects
Work (thermodynamics) ,Materials science ,Hydrogen ,General Chemical Engineering ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,Nitride ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Adsorption ,chemistry ,Chemical physics ,Desorption ,Materials Chemistry ,Density functional theory ,Lithium ,0210 nano-technology ,MXenes - Abstract
Density functional theory calculations are employed to systematically investigate the trend of hydrogen evolution reaction (HER) performance of oxygen-terminated MXenes. By studying 30 transition-metal carbides and 30 transition-metal nitrides, Mn+1CnO2 and Mn+1NnO2 (M = Sc, Cr, Hf, Mo, Nb, Ta, Ti, V, W, Zr; n = 1, 2, 3), the tendency of oxygen desorption after hydrogen adsorption is elucidated to play a key role in HER performance of oxygen-terminated MXenes. On the basis of these observations, we propose a suitable HER descriptor, oxygen vacancy formation energy (Ef), which scales linearly with the adsorption free energy of hydrogen, ΔGH. In addition, this new descriptor is linearly correlated with the lithium binding strength on oxygen-terminated MXenes. Therefore, Ef is a universal descriptor for identifying the trend of adsorption processes where adsorbed species donate electrons to oxygen-terminated MXenes. This work provides a general guideline for large-scale screening of promising MXene-based mat...
- Published
- 2018