Two-Dimensional Phosphorus-Doped Carbon Nanosheets with Tunable Porosity for Oxygen Reactions in Zinc-Air Batteries

Abstract

Large-sized two-dimensional phosphorus-doped carbon nanosheets (2D-PPCN) with tunable porosity were synthesized via a multifunctional templating method. A single inexpensive solid precursor, phosphorus pentoxide, is combined with common saccharides in a stepwise multiple templating process for 2D construction, phosphorus doping, and regulated micro-/mesopore creation. This reliable 2D porous carbon production technique can potentially be utilized in a variety of energy storage and conversion fields. The effects of different porous structures on the electrocatalytic activity of 2D-PPCN based electrocatalysts are specifically investigated in this work. The interconnected open-pore system and high specific surface area result in a high catalytic efficiency for both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). When integrated into an air-breathing cathode for rechargeable Zn-air batteries, the best-performing 2D-PPCN demonstrates better cell performance than a noble metal benchmark catalyst and a higher durability with over 1000 charge–discharge cycles.