Mechanistic and Experimental Study of the Formation of MoS2/HKUST-1 Core-Shell Composites on MoS2 Quantum Dots with an Enhanced CO2 Adsorption Capacity

In this study, a new "one-pot" synthesis method was developed for the fabrication of HKUST-1 on MoS2 quantum dots (QDs) to form a core-shell structure. It is proved that the HKUST-1 self-assembles on MoS2 QDs to form a core-shell structure, which exhibits a high surface area of 1638.9 m(2)/g and enhances CO2 uptake to 4.64 mmol/g as compared with HKUST-1 alone. The density functional theory (DFT) calculations revealed that the growth of HKUST-1 on MoS2 QDs starts from the adsorption of Cu2+ cations on the MoS2 (001), followed by the Cu2+ cations bonding with trimesic acid (TMA) anions. In addition, the interactions between a CO2 molecule and the (MoS2 + SBU) (secondary building unit = SBU) unit were studied using DFT calculations to show the mechanism of CO2 adsorption on the MoS2 /HKUST-1 core-shell composite. It is found that the MoS2 QDs induce stronger electrostatic forces on CO2 than HKUST-1 alone, which subsequently contributes to enhancing the adsorption of CO2 on the MoS2 /HKUST-1 core-shell composite.