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The search of excellent electrocatalysts for the two-electron O2-reduction reaction (2e− ORR) is of great importance for the green synthesis of H2O2. This study developed a computational framework using density functional theory (DFT) and ab initio molecular dynamic simulation (AIMD) to investigate the influence of acid electrolytes, particularly H coverage, on the s-band center of a single-atomic Ag catalyst, leading to improved catalytic selectivity for the ORR. Specially, the screened catalyst Ag@Ti2C exhibited remarkable intrinsic performance for 2e− ORR with an overpotential of only 0.06 V. In acidic electrolytes, Ag@Ti2C selectively bound to O-containing and H species, forming Ag@Ti2CO2Hx. The introduction of O functional groups improved the electron delocalization, enhancing O2–Ag interactions. Significantly, the surface O atom's p-band center exhibited a parabolic trend with the H coverage on Ag@Ti2CO2. Consequently, the catalyst exhibited an optimal overpotential of 0.08 V for 2e− ORR at an H atom coverage of 22.2%. It was found that the surface O p-state played a crucial role in mediating the s-band center of the single-atomic Ag catalyst, significantly influencing its catalytic performance in the ORR. [ABSTRACT FROM AUTHOR]

Studying the effect of the coordination field on the catalytic property is critical for the rational design of outstanding electrocatalysts for H2O2 synthesis. Herein, via density functional theory (DFT) calculations and ab initio molecular dynamic (AIMD) simulations, we built an effective computational framework to identify the synergetic effect of an aqua ligand and metal ion on the 2e− ORR catalytic performance under gas condition and aqua solvent. Specifically, the screening results of 29 single-atom catalysts (SACs), TM@C6N6 (TM = transition metal), indicated that Cu@C6N6 features excellent catalytic property with thermal stability, lowest 2e− ORR overpotential (0.02 V) and high selectivity of 99.99%. Once an aqua ligand binds with the Cu site, the activity is reduced to the overpotential of 0.42 V and the selectivity decreased slightly (99.98%) due to the reduction of the adsorption strength for the reaction intermediates. A combination of geometric structures and electronic properties revealed that such changes are correlated with the charge of the Cu site. Furthermore, based on molecular orbital theory, the essence of the high catalytic property deeply lies in the effect of the moderate electron back donation bond (dyz & dxz→) between Cu and O2. This work will provide a route to better design high-performance SACs for H2O2 synthesis effectively. [ABSTRACT FROM AUTHOR]

In this study, we have facilely developed a SnO2-based electrocatalyst (SnO2-VO@N–C), which can combine together the favorable structure features of oxygen vacancies, porosity, and full-coating with N-doped carbon layers (N–C). Our experimental and theoretical calculation results indicated that with the facile engineering of oxygen vacancies and the full-coating of the N-doped carbon layer, the adsorption/activation of CO2 and charge transfer can be promoted in the CO2 reduction process, making SnO2-VO@N–C the electrocatalyst with improved activity and selectivity (FEHCOOH = 84%) toward the reduction of CO2 to HCOOH. [ABSTRACT FROM AUTHOR]

Studying the effect of the coordination field on the catalytic property is critical for the rational design of outstanding electrocatalysts for H 2 O 2 synthesis. Herein, via density functional theory (DFT) calculations and ab initio molecular dynamic (AIMD) simulations, we built an effective computational framework to identify the synergetic effect of an aqua ligand and metal ion on the 2e - ORR catalytic performance under gas condition and aqua solvent. Specifically, the screening results of 29 single-atom catalysts (SACs), TM@C 6 N 6 (TM = transition metal), indicated that Cu@C 6 N 6 features excellent catalytic property with thermal stability, lowest 2e - ORR overpotential (0.02 V) and high selectivity of 99.99%. Once an aqua ligand binds with the Cu site, the activity is reduced to the overpotential of 0.42 V and the selectivity decreased slightly (99.98%) due to the reduction of the adsorption strength for the reaction intermediates. A combination of geometric structures and electronic properties revealed that such changes are correlated with the charge of the Cu site. Furthermore, based on molecular orbital theory, the essence of the high catalytic property deeply lies in the effect of the moderate electron back donation bond (d yz & d xz → ) between Cu and O 2 . This work will provide a route to better design high-performance SACs for H 2 O 2 synthesis effectively.

In this study, we have facilely developed a SnO 2 -based electrocatalyst (SnO 2 -V O @N-C), which can combine together the favorable structure features of oxygen vacancies, porosity, and full-coating with N-doped carbon layers (N-C). Our experimental and theoretical calculation results indicated that with the facile engineering of oxygen vacancies and the full-coating of the N-doped carbon layer, the adsorption/activation of CO 2 and charge transfer can be promoted in the CO 2 reduction process, making SnO 2 -V O @N-C the electrocatalyst with improved activity and selectivity (FE HCOOH = 84%) toward the reduction of CO 2 to HCOOH.