An Overview of Oxygen Reduction Electrocatalysts for Rechargeable Zinc-Air Batteries Enabled by Carbon and Carbon Composites

Abstract

The merits, such as high specific capacity, less self-discharge and high storage life, make Zinc (Zn)-air batteries promising to serve as energy storage and conversion equipment to effectively solve the energy crisis and environmental pollution caused by the rapid increasing global energy consumption, especially the use of fossil energy. However, the applications and further deployments of the Zn-air batteries depend on costly noble metal as cathodes and are limited by sluggish electrochemical reaction kinetics. As one of the competitive alternatives to noble metals, carbon-based materials such as metal/carbon, nonmetal atom/carbon, metal oxide/carbon and metal-metal oxide-heteroatom/carbon materials exhibit the advantages of structural diversity, high porosity, excellent volume conversion efficiency and non-toxicity. With the emphases on structural improvement and composition optimization, this article summarizes the advances in the development of oxygen reduction reaction (ORR) electrocatalyst based on various carbon contained composites for Zn-air battery cathodes. Furthermore, the challenges and perspectives of the research directions on the Zn-air battery with carbon contained composites as catalyst are discussed in detail.

A general strategy to enhance the electrochemical activity and energy density of energy-storage materials through using sintering aids with redox activity: a case study of Mo4Nb26O77

“…Metal-ion batteries, such as lithium-ion batteries (LIBs), are playing an increasingly important role in various small-scale devices and large-scale facilities. [1][2][3][4][5][6] Their energy-storage materials, such as niobates, can be prepared through conventional solid-state reaction methods and wet-chemical synthesis methods (solvothermal method, sol-gel method, electrospinning method, etc.). [7][8][9] The wet-chemical synthesis methods usually use expensive organometallic salts, and the resultant products generally show low tap densities.…”

Co3O4 nanoparticle-dotted hierarchical-assembled carbon nanosheet framework catalysts with the formation/decomposition mechanisms of Li2O2 for smart lithium–oxygen batteries

“…Energy shortage and environmental problems have led to a positive search in energy consumption and conservation. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] Among multitudinous types of storage and conversion technologies, rechargeable Li-O 2 batteries [21][22][23][24] (LOBs) are regarded as the potential candidates for energy storage owing to their ultra-high theoretical energy density reaching 3600 W h Kg −1 , originating from the process of oxygen being reduced to form lithium peroxide (2Li + O 2 ↔ Li 2 O 2 , 2.96 V vs. Li/Li + ), which is nearly ten times higher than commercialized lithium-ion batteries. [25][26][27] However, in comparison with an ideal reaction process, complex reaction mechanisms and possible by-products exist resulting in challenges [28][29][30] including inferior specific capacity, low round trip energy efficiency, poor cycle performance, which hinder its further development.…”

N, P Self-Doped Porous Carbon Material Derived from Lotus Pollen for Highly Efficient Ethanol–Water Mixtures Photocatalytic Hydrogen Production

“…However, the application of P, which is commonly used for the treatment of catalyst in industry, is less involved in photocatalysis [ 23 , 24 ]. In fact, due to the changes in many properties of carbon materials such as optics and electricity [ 25 , 26 ], researchers believe that P can be used as a next-generation doping study of hetero elements. The current methods for preparing P-doped carbon mainly include: (1) post-treatment of carbon materials with P-containing substances such as phosphoric acid; (2) blending P-containing precursors with carbon-containing precursors and calcining them; and (3) vapor deposition using P-containing and carbon-containing precursors material [ 27 , 28 ].…”