Atomic Pt Promoted N-Doped Carbon as Novel Negative Electrode for Li-Ion Batteries

ACS Appl Mater Interfaces. 2019 Oct 16;11(41):37559-37566. doi: 10.1021/acsami.9b10533. Epub 2019 Oct 4.

Abstract

In this work, platinum single-atom enhanced mushroom-based carbon (Pt1/MC) materials have been facilely synthesized and served as novel electrode materials in lithium-ion batteries (LIBs). The as-synthesized Pt1/MC active material shows a uniform dispersion of isolated Pt atoms on an MC support with high specific surface area and large total pore volume. As a negative electrode material for LIBs, the Pt1/MC exhibits excellent electrochemical properties, which retains a capacity of 846 mA h g-1 after 800 cycles at 2 A g-1 and 349 mA h g-1 (near to the theoretical capacity of graphite) after 6000 cycles at a high current density of 5 A g-1. The remarkable high capacity and excellent cycling stability can be attributed to their porous nanostructures and atomic-Pt-enhanced lithium-ion storage. Atomic Pt can compound with Li+ ions to form a platinum-lithium alloy during the discharge and charge process. Density functional theory (DFT) calculations are performed to verify that the PtLi5 alloy is the most stable intermedium on the MC substrate, which further enhances the lithiation and delithiation kinetics. This novel perspective is helpful to explore next-generation negative electrode materials with high capacities and good stabilities for LIBs.

Keywords: Li-ion batteries; PtLi5 alloy; atomic Pt; density functional theory; electrode materials.