Designing Electrophilic and Nucleophilic Dual Centers in the ReS Plane toward Efficient Bifunctional Catalysts for Li-CO Batteries.

Two-dimensional transition metal dichalcogenides (TMDCs) show great potential as efficient catalysts for Li-CO batteries. However, the basal plane engineering on TMDCs toward bifunctional catalysts for Li-CO batteries is still poorly understood. In this work, density functional theory calculations reveal that nucleophilic N dopants and electrophilic S vacancies in the ReS plane tailor the interactions with Li atoms and C/O atoms in intermediates, respectively. The electrophilic and nucleophilic dual centers show suitable adsorption with all intermediates during discharge and charge, resulting in a small energy barrier for the rate-determining step. Thus, an efficient bifunctional catalyst is produced toward Li-CO batteries. As a result, the optimal catalyst achieves an ultrasmall voltage gap of 0.66 V and an ultrahigh energy efficiency of 81.1% at 20 μA cm, which is superior to those of previous catalysts under similar conditions. The introduction of electrophilic and nucleophilic dual centers provides new avenues for designing excellent bifunctional catalysts for Li-CO batteries.