Toward Highly Efficient Electrocatalyst for Li–O₂ Batteries Using Biphasic N-Doping Cobalt@Graphene Multiple-Capsule Heterostructures

Abstract

For the promotion of lithium-oxygen batteries available for practical applications, the development of advanced cathode catalysts with low-cost, high activity, and stable structural properties is demanded. Such development is rooted on certain intelligent catalyst-electrode design that fundamentally facilitates electronic and ionic transport and improves oxygen diffusivity in a porous environment. Here we design a biphasic nitrogen-doped cobalt@graphene multiple-capsule heterostructure, combined with a flexible, stable porous electrode architecture, and apply it as promising cathodes for lithium-oxygen cells. The biphasic nitrogen-doping feature improves the electric conductivity and catalytic activity; the multiple-nanocapsule configuration makes high/uniform electroactive zones possible; furthermore, the colander-like porous electrode facilitates the oxygen diffusion, catalytic reaction, and stable deposition of discharge products. As a result, the electrode exhibits much improved electrocatalytic properties associated with unique morphologies of electrochemically grown lithium peroxides.

Atomic‐Layer‐Deposited Amorphous MoS2 for Durable and Flexible Li–O2 Batteries

“…Among all kinds of cathode materials in LOBs, the carbon material, especially carbon nanotubes (CNT) and graphene, is most popular because of its merits of high conductivity, low cost, good ORR activity, large specific surface, and tunable nanostructure . However, the drawback of pure carbon materials is the inevitable corrosion during the discharge/charge process .…”

Functionalization of 2D materials for enhancing OER/ORR catalytic activity in Li–oxygen batteries

“…Nevertheless, noble metal catalyst particles (such as Au, Pt, and MnO 2 ) that are typically used in these systems are quite expensive. Furthermore, their catalytic properties are mostly effective in enhancing ORR rather than OER, for which the high overpotential is more crucial 14 . In addition, the carbon substrate in these cathode systems is readily oxidized at higher voltage (above 3.0 V) 15 , thereby reacting with the discharge products in Li-O 2 batteries to form lithium carbonate (Li 2 CO 3 ) 16,17 .…”

“…The emergence of two-dimensional (2D) materials over recent years has offered a number of promising candidates for improving the electrocatalysis of ORR/OER due to their high specific surface area and high surface density of active catalytic sites. Some materials of interest to Li-O 2 batteries are nitrogen-doped graphene 26 , hexagonal boron nitride (h-BN) on Ni surfaces 14,27 , and molybdenum carbide (Mo 2 C) 28 . Layered transition metal-carbide and metalnitrite MXenes with the general formula of M n+1 X n , with M being a transition metal and X = {C, N}, are highly stable 2D materials containing 2n + 1 layers of atoms 29 (see Supplementary Fig.…”

Research Progress for the Development of Li‐Air Batteries: Addressing Parasitic Reactions Arising from Air Composition

“…[44][45][46][47] Carbon nanotubes (CNTs) with high electrical conductivity, large surface area, and porous three-dimensional networks with abundant channels have been employed as a catalyst for Li 2 CO 3 decomposition. [44][45][46][47] Carbon nanotubes (CNTs) with high electrical conductivity, large surface area, and porous three-dimensional networks with abundant channels have been employed as a catalyst for Li 2 CO 3 decomposition.…”