Popcorn Inspired Porous Macrocellular Carbon: Rapid Puffing Fabrication from Rice and Its Applications in Lithium–Sulfur Batteries

Abstract

Abstract The advancement of electrochemical energy storage is closely bound up with the breakthrough of controllable fabrication of energy materials. Inspired by a popcorn fabrication from corn raw, herein a unique porous macrocellular carbon composed of cross‐linked nano/microsheets by a powerful puffing of rice precursor is described. The rice is directly puffed with a volume enlargement of ≈20 times when it is instantaneously released from a sealed environment with a high pressure of 1.0 MPa at 200 °C. Interestingly, when metal (e.g., Ni) nanoparticles are embedded in the puffed rice derived carbon (PRC), high‐quality PRC/metal composites are achieved with attractive properties of a high electrical conductivity of ≈7.2 × 10 4 S m −1 , a large porosity of 85.1%, and a surface area of 1492.2 m 2 g −1 . The PRC/Ni are employed as a host in lithium–sulfur batteries. The designed PRC/Ni/S electrode exhibits a high reversible capacity of 1257.2 mA h g −1 at 0.2 C, a prolonged cycle life (821 mA h g −1 after 500 cycles), and enhanced rate capability, much better than other counterparts (PRC/S and rGO/S). The excellent properties are attributed to the advantages of PRC/Ni network with a high electrical conductivity, strong adsorption/blocking ability for polysulfides, and interconnected porous framework.