Copper is a well-known metal for catalyzing the electrochemical CO 2 reduction reaction (CO 2 RR) toward valuable hydrocarbons and alcohols. Here, using a combined density functional theory and microkinetic modeling approach, we systematically investigated 11 bimetallic M@Cu(211) single-atom stepped surface alloys for their CO 2 RR activity. It is revealed that the stepped M edge is most likely to be the active site for CO 2 RR. The primary reaction pathway is identified as *COOH → *CO → *CHO with the potential-determining step of *CO + H + + e − → *CHO, leading to either CH 4 or CH 3 OH formation at more negative potential. Especially, Ru@Cu(211) and Fe@Cu(211) are both predicted to be most efficient in promoting CO 2 RR toward CH 4 owing to their breaking of the coupled scaling relations of key intermediates' binding at the active site. Furthermore, the binding strength of *CO and *OH can be used as a good descriptor for differentiating various M@ Cu(211) for CO 2 RR activity and selectivity, and specifically, the moderate oxophilic and carbophilic elements of M are preferred. Our study highlights the utmost importance of breaking the linear scaling relations of key intermediates' binding at the active site for boosting CO 2 RR performance.

Gaining mechanistic insights into the active site is essential to rational design of a high-performance cathode catalyst for the electrochemical CO2 reduction reaction (CO2 RR). Here, by means of density functional theory and computational hydrogen electrode methods, we investigated synergy of a metallic NiCo dimer anchored on a C2N graphene matrix for promoting the CO2 RR. It is found that heterometallic NiCo@C2N (U L = −0.25 V) outperforms homometallic Co2@C2N (U L = −0.30 V) and Ni2@C2N (U L = −0.67 V) for catalyzing the CO2 RR toward CH4 formation owing to its synergy within the dimer. We emphasize the impact of co-adsorbed *H, *OH, and *CO intermediates on the CO2 RR, revealing that multiple competing reaction channels are accessible from viable co-adsorbates. Moreover, strongly-bound *H, *OH, and *CO intermediates are predicted not to deactivate metallic dimer sites for a continuous cycle of the CO2 RR. Our study could provide a theoretical basis for optimizing a metallic dimer anchored on a N-doped graphene matrix for achieving a more advanced CO2 RR cathode with enhanced activity and selectivity.

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In this work, the solubilities of (R)- and (R,S)-crizotinib in six solvents including methanol, ethanol, 1-propanol, 1-butanol, ethyl acetate, and n-hexane were first measured by a static method in the temperature range from 273.15 to 323.15 K at atmospheric pressure. Then, molecular simulations were performed to predict the crystal structures of (R)-crizotinib and (R,S)-crizotinib from their powder X-ray diffractograms and the solubilities in the above organic solvents using the Gibbs free energy calculation approach via the sublimation cycle. The results showed that the solubilities of (R)- and (R,S)-crizotinib in the selected solvents generally increased with the increasing temperature, and at room temperature the molar fraction solubility order was methanol > 1-butanol > 1-propanol > ethanol > ethyl acetate > n-hexane. The (R)-crizotinib crystal had a monoclinic unit cell, while the (R,S)-crizotinib crystal had a triclinic one. In particular, though it was first applied to the solubility estimation for water-insoluble drug compounds in organic solvents, the Gibbs energy calculation approach developed gave a desirable solubility prediction performance with a root-mean-square error (RMSE) of 0.7638 log S units for (R)-crizotinib and 1.1577 log S units for (R,S)-crizotinib in the selected solvents, respectively. Furthermore, the difference in the solubilities of (R)-crizotinib in different solvents mainly resulted from the different Gibbs free energies for solvation between solute and solvent other than those for sublimation. However, as to the difference in the solubilities of (R)- and (R,S)-crizotinib in the same solvent, the Gibbs free energy for sublimation made more of a contribution than that for solvation. Finally, on the basis of the solid-state characterization, the nature of crystalline (R,S)-crizotinib was confirmed to be a racemic compound. All these results shall provide pharmaceutical industry with a better understanding of this chiral system for crystallization resolution.

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