First Application of Nitrogen-Doped Carbon Nanosheets Derived from Lotus Leaves as the Electrode Catalyst for Li-CO2/O2 Battery

Abstract

The development of Li-CO2/O2 battery with high energy density and long-term stability is urgently needed to fulfill the carbon neutralization and pollution-free environment targets. The biomass-derived heteroatom-doped carbon catalyst with the combination of high-efficiency catalytic activity and sustainable supply is a promising cathode catalyst in Li-CO2/O2 battery. Specifically, the unique morphology and mesopore structure can promote the transfer of CO2, O2, and Li+. Abundant channel pores can provide discharge products accommodation to the largest extent. Nitrogen dopant, the commonly recognized active sites in carbon, can improve the electron conductivity and accelerate the sluggish kinetic reaction. Therefore, utilizing the louts leaves as the precursor, we successfully prepare the cellular-like nitrogen-doped activated carbon nanosheets (N-CNs) through the appropriate pyrolysis carbonization method. The as-synthesized carbon nanosheets display a three-dimensional interconnecting pore structure and abundant N-dopant actives, which dramatically improve the electrochemical catalytic activity of N-CNs. The Li-CO2/O2 battery with the N-CNs cathode delivers a high discharge capacity of 9825 mAh g−1, low overpotential of 1.21 V, and stable cycling performance of 95 cycles. Thus, we carry out a facile method for N-doped carbon nanosheets preparation derived from the cheap natural biomass, which can be the effective cathode catalyst for environmental-friendly Li-CO2/O2 battery.