Adsorption is essential for many processes on surfaces; therefore, an accurate prediction of adsorption properties is demanded from both fundamental and technological points of view. Particularly, identifying the intrinsic determinants of adsorption energy has been a long-term goal in surface science. Herein, we propose a predictive model for quantitative determination of the adsorption energies of small molecules on metallic materials and oxides, by using a linear combination of the valence and electronegativity of surface atoms and the coordination of active sites, with the corresponding prefactors determined by the valence of adsorbates. This model quantifies the effect of the intrinsic properties of adsorbates and substrates on adsorbate-substrate bonding, derives naturally the well-known adsorption-energy scaling relations, and accounts for the efficiency and limitation of engineering the adsorption energy and reaction energy. All involved parameters are predictable and thus allow the rapid rational design of materials with optimal adsorption properties.

Electroreduction is a promising approach to transform CO2, a greenhouse gas, into valuable hydrocarbons and could help mitigate the global warming effect. However, the high overpotential associated with known catalysts prohibits the adoption of CO2 electroreduction at the industrial scale. Finding an efficient catalyst is the key to overcome this hurdle. Understanding the factors that influence activity and selectivity is an essential step in systematically searching for efficient catalysts, and effective descriptors can guide such a search. In this work, we propose two effective descriptors: the CO2/CO adsorption energy descriptor and the carbon monomer mobility descriptor. The former is a general descriptor for various CO2 reduction reactions with products like CO, HCOOH, and CH4/C2H4; the latter is specific for reductions leading to CH4/C2H4. We further use these descriptors to analyze a variety of alloy catalysts and identify which among these may perform best at the reduction of CO2 to different products.

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Abstract. The impact property of a high-strength grade 42CrMoE alloy steel was investigated under varied insert lengths using reconstitution method. A new full-field strain measurement method was employed to explore the plastic deformation region of the steel. Meanwhile, in order to quantitatively examine the insert length influence, an instrumented impact method was proposed to analysis the impact property. The results have successfully demonstrated that inserts equal to or larger than 20 mm can be used to obtain valid data for 42CrMoE.